Entries |
Document | Title | Date |
20080225934 | METHOD FOR DETERMINING A CORRECTED VARIANCE REPRESENTATIVE OF THE CONDITION OF RECEPTION OF SIGNALS REPRESENTATIVE OF SYMBOLS - The present invention concerns a method for determining a corrected estimated variance representative of the condition of reception of signals representative of symbols transferred by an emitter to a receiver through a communication channel, wherein the method comprises the step, executed by the receiver, of producing an estimation of the variance by a Wiener channel estimator comprising a linear filter of which coefficients are determined at least from a given average signal to interference plus noise ratio value, the method being characterised in that it comprises farther step, executed by the receiver, of:
| 09-18-2008 |
20080240216 | Link adaptation method - A method, where data is transmitted from a network node to user equipment in a succession of communication frames. An estimate indicative of the quality of the user equipment transmission channel in a reference communication frame is ascertained, and modified by an amount that varies in dependence on a configuration of the resources allocated to the user equipment in the reference communication frame. The modified estimate is used in selecting one or more connection parameters for a data transmission in a target communication frame. This improves the adaptation of the transmission parameters to the existing channel conditions | 10-02-2008 |
20080240217 | Cinr Estimating Method and Device Using Preamble in Ofdm - A device and method for estimating a carrier to interference-plus-noise ratio (CINR) in an OFDM system are provided. The CINR estimating method includes (a) receiving a preamble symbol and transmit subcarrier transmitted from a base station; (b) calculating an interference power and noise power using the preamble symbol and transmit subcarrier; (c) calculating a receive power used for the base station to transmit a preamble and data symbol; (d) estimating a preamble CINR value using an interference power, a noise power, and a receive power; (e) calculating the noise power from a subcarrier not transmitting a preamble; and (f) calculating an average CINR of data subcarriers using the preamble CINR value and the noise power. With such a method, a precise carrier to interference-plus-noise ratio (CINR) can be estimated using a preamble when the preamble power is amplified in comparison with the data symbol power, the subcarriers are differently applied for the respective cells, and the traffic of the data area is partially loading. | 10-02-2008 |
20080260012 | Receiver and receiving method - An apparatus, including a detection unit configured to perform a non-linear detection on a receive signal, a first estimator configured to estimate a first quality measure based on the receive signal, and a second estimator configured to estimate a second quality measure dependent on the first quality measure and a performance measure of the detection unit is provided. | 10-23-2008 |
20080279268 | Method for measuring noise, apparatus for measuring noise, and program for measuring noise - The frequency of signals under test is stabilized and the noise components of the signals under test whose frequency has been stabilized is measured. When the noise of the object under test is related to frequency or phase, the measured noise components are corrected based on the properties of frequency stabilization. | 11-13-2008 |
20080279269 | SYSTEMS AND METHODS FOR LOOP TERMINATION DETECTION BASED ON PER-PORT CALIBRATION - Systems and methods for performing loop termination are described. One embodiment is a method that comprises receiving a per-port calibrated echo signal of a loop under test, receiving a region designation and a loop length for the loop under test, and determining whether the loop is terminated by a short or open termination based on phase of the per-port calibrated echo signal. | 11-13-2008 |
20080291990 | Reception quality measuring apparatus and reception quality measuring method - A reception quality measuring apparatus of the present invention comprises a first sub-carrier averaging unit for averaging and outputting a channel gain after equalization estimated on the basis of the pilot signal over a sub-carrier, a first power calculation unit for calculating the power of a signal output from the first sub-carrier averaging unit and outputting the same as signal power, a pilot replica generator for generating and outputting a pilot signal replica with respect to a zero-timing signal component based on the zero-timing signal component when a signal x(n) in the time domain after equalization corresponding to the equalized signal is n=0, and also based on a previously set pilot code characteristic, a subtractor for subtracting the pilot signal replica output from the pilot replica generator from the equalized signal and outputting the result as an interference signal, a second power calculation unit for calculating and outputting the power of the interference signal output from the subtractor, a second sub-carrier averaging unit for averaging the power output from the second power calculation unit over the sub-carrier and outputting the result as interference power, and a divider for dividing the signal power output from the first power calculation unit by the interference power output from the second sub-carrier averaging unit to calculate a reception quality after equalization. | 11-27-2008 |
20080298449 | Method and an apparatus for measuring error vector magnitude, and a measuring apparatus or signal source evaluated or assessed by this method - At least one property of a measuring apparatus that is different property from the error vector magnitude is measured, or a previously measured value or a predetermined value of the at least one property is prepared; based on the measured value or specification value of each of the at least one property, each corresponding noise power within a specific frequency range is found; and the error vector magnitude is calculated based on the noise power. | 12-04-2008 |
20080298450 | Frequency Band Adaptive Wireless Communication - A system, apparatus and method is disclosed for multiband wireless communication. Frequency bands and/or transmission formats are identified as available within a range for wireless communication. Signal quality metrics for each frequency band are evaluated by a receiver to identify qualified frequency bands. The qualified frequency bands can be ranked according to one or more signal quality metrics, where the list of qualified bands can be communicated to a transmitter. The transmitter is arranged to evaluate the list of qualified bands and select a communication method based on the available frequency bands and a selected communication optimization scenario. Multiple frequency bands and communication methods can be utilized by the transmitter such that a combination of licensed, unlicensed, semilicensed, and overlapped frequency bands can be simultaneously used for communication. The receiver continually monitors communications and can report link performance to the transmitter for adaptive control of the selected communication methods. | 12-04-2008 |
20080298451 | APPARATUS AND METHOD FOR ESTIMATING CARRIER-TO-INTERFERENCE AND NOISE RATIO IN A COMMUNICATION SYSTEM - An apparatus and method for estimating a Carrier-to-Interference and Noise Ratio (CINR) in a communication system are provided. In the apparatus and method a signal having a traffic allocation available area that includes a preamble allocation available area is generated by Fast Fourier Transform (FFT)-processing a received symbol, power values of preamble tones included in the preamble allocation available area are calculated, a carrier power value is calculated using the power values of the preamble tones, a partial noise-interference power value is calculated using power differences between the preamble tones and power values of remaining tones other than the preamble tones, a noise power value is calculated using power values of tones included in a noise power estimation area being an area except for the preamble allocation available area in the traffic allocation available area, and the CINR is calculated using the carrier power value, the partial noise-interference power value, and the noise power value. | 12-04-2008 |
20080310490 | Signal Generator and User Interface for Adding Amplitude Noise to Selected Portions of a Test Signal - A signal generator generates amplitude noise on a selected segment of a test signal. A user interface is used for selecting a segment of the test signal and an associated power level for applying amplitude noise at a selected power level to the test signal segment. A signal processing unit compiles the selected power level of the selected segment with the test signal to generate digital data representative of the test signal with selected segments having amplitude noise. A waveform generator receives the digital data and generating a test signal output having amplitude noise at selected segments of the test signal. The method includes the steps of: selecting a segment of the test signal to add amplitude noise; selecting a power level for the amplitude noise; and applying the amplitude noise at the selected power level to the selected segment of the test signal. | 12-18-2008 |
20080317111 | Video Quality Measurement - This application is concerned with a non-intrusive video quality measurement method, in particular where the video signal having: an original form; encoded form in which video signal has been encoded using a compression algorithm utilising a variable quantiser step size such that the encoded signal includes a quantiser step size parameter; and, a decoded form in which the encoded video signal has been at least in part reconverted to the original form. The method comprises the steps of: a) generating a first quality measure which is a function of said quantiser step size parameter; b) generating a second quality measure which is a function of the spatial complexity of the frames represented by the video signal in the decoded form; and, c) combining the first and second measures in order to obtain an estimate for the subjective visual quality of the decoded video. | 12-25-2008 |
20090003425 | Inter-carrier Interference Measurement In Orthogonal Frequency Division Multiplexing Systems - A system for measuring inter-carrier interference (ICI) in an OFDM system includes a test symbol generator coupled to a transmitter of the OFDM system to generate an N*N orthogonal matrix having N*N test symbols, and to send the test symbols in a test symbol stream via the transmitter to a receiver of the OFDM system. The N*N test symbols are arranged by the test symbol generator into an N*N orthogonal matrix before being sent to the receiver. The system also includes an ICI measuring module coupled to the receiver to detect the N*N test symbols received in the receiver and to arrange the test symbols as a receiving matrix in the same way as the orthogonal matrix in the transmitter. The ICI measuring module outputs the receiving matrix as an ICI matrix of the OFDM system, wherein an element on the kth row, lth column of the ICI matrix represents interference from the lth sub-carrier on the kth sub-carrier, wherein k≠l. | 01-01-2009 |
20090003426 | Adaptive Error Counter for a Wireless Field Device - A transmitting and receiving unit is provided for a field device for measuring a filling level or a pressure, which has an adaptive error counter. In this way, the sensitivity of the error detection may be adapted to individual needs or to the present length of the communications section. Thus, during wireless communication an optimally set error counter may fundamentally be used according to the distance to be covered without any adjustment needing to be made for this on the user side. | 01-01-2009 |
20090016420 | APPARATUS AND METHOD FOR MEASURING CARRIER TO INTERFERENCE AND NOISE RATIO - Provided are an apparatus and method for measuring a carrier-to-interference and noise ratio (CINR) using a pilot symbol in a digital communication system, and more particularly, to an apparatus and method for measuring a CINR by estimating a data signal, noise, and an interference signal from a pilot symbol in a digital communication system using orthogonal frequency division multiplexing (OFDM)/orthogonal frequency division multiplexing access (OFDMA). The apparatus includes: a pilot symbol acquisition unit for acquiring the pilot symbol from a baseband frequency signal; a signal estimation unit for estimating a pilot signal and a data signal from the pilot symbol; a power calculation unit for calculating a power value of the estimated data signal and calculating a power value of a noise signal from a difference between the pilot symbol and an estimated pilot signal; and a CINR calculation unit for calculating a CINR on the basis of the power values of the data and noise signals. Thus, a pilot symbol is used for more easily and precisely measuring a CINR of a received signal, and scheduling of a base station and transmission power control of a terminal are performed on the basis of the measured CINR. | 01-15-2009 |
20090034598 | METHOD AND APPARATUS TO COMPUTE A NOISE POWER ESTIMATE IN A WCDMA NETWORK BASED ON DEDICATED PHYSICAL CONTROL CHANNEL (DPCCH) PROCESSING - A method to process DP bits within a WCDMA receiver where a noise estimation that may be implemented within hardware is provided for improved flexibility and performance. DPCH pilot symbols are received, quantized, channel compensated and combined. The computation of an SNR estimate based on the combined DPCH pilot symbols is provided. Noise estimation is used as part of the SNR estimation of the DP bits (used for downlink power control). This method does not rely on the assumption that the channel is constant over the DP field, while prior methods did. | 02-05-2009 |
20090041105 | COMMUNICATION CONTROL METHOD, RECEIVING STATION APPARATUS, TRANSMITTING STATION APPARATUS, AND COMMUNICATION SYSTEM - A receiving station apparatus controls a number of null carriers included in a transmission signal transmitted by a transmitting station apparatus in a communication system adopting a multicarrier modulation system to suppress inter-carrier interference by using the null carrier. For example, a reception-quality measuring unit measures a reception quality of a subcarrier group forming the transmission signal, and a number-of-null carriers determining unit determines the number of null carriers included in a next transmission signal based on the reception quality. | 02-12-2009 |
20090052512 | LINK ADAPTATION SYSTEM USING DOPPLER FREQUENCY AND METHOD USING THE SAME - A link adaptation system using a Doppler frequency is provided. The link adaptation system includes: a Doppler frequency estimation unit to estimate a Doppler frequency of a signal transmitted via a wireless channel; a Signal to Noise Ratio (SNR) measurement interval determination unit to determine an SNR measurement interval of the signal transmitted via the wireless channel based on the estimated Doppler frequency; and an SNR measurement unit to measure an SNR of the signal based on the determined SNR measurement interval. | 02-26-2009 |
20090060014 | SYSTEM AND METHOD FOR AUTOMATED LINK QUALITY MEASUREMENT FOR ADAPTIVE MODULATION SYSTEMS USING NOISE LEVEL ESTIMATES - A communications system includes a transmitter that transmits a modulated signal having encoded communications data over a communications channel. The transmitter adjusts one of at least modulation and coding at the transmitter based on the received channel state information of the transmitted signal. A receiver determines received signal metrics from the modulated signal. A noise power estimator estimates the noise power of the received communications signal by collecting N data samples from the communications signals, forming a covariance matrix of the N data samples based on a model order estimate, computing the eigenvalue decomposition of the covariance matrix and ranking resultant eigenvalues from the minimum to the maximum for determining the noise power of the received signal. At least one of modulation and coding are adjusted based on the monitored link quality of the communications channel to enhance use of the available channel capacity. | 03-05-2009 |
20090060015 | SYSTEM AND METHOD FOR ESTIMATING NOISE POWER LEVEL IN A MULTI-SIGNAL COMMUNICATIONS CHANNEL - A system estimates noise power in a scalar, multi-signal communications channel. A data sampler collects N data samples from communications signals received from the communications channel. A module forms a covariance matrix of the N data samples based on a model order estimate. A module also computes the eigenvalue decomposition of the covariance matrix and ranks resultant eigenvalues from the minimum to the maximum for determining the noise power. | 03-05-2009 |
20090074046 | Data Structure Boundary Synchronization Between a Transmitter and Receiver - Synchronization between a transmitter and a receiver with respect to the boundary of higher-layer logical data structures is improved by considering both the statistical likelihood of the value of a transmitted boundary indicator and the quality of the channel during the transmission. A boundary indicator received under poor channel quality, that is decoded to a statistically unlikely value, is suspect and one or more retransmission is requested. A reliable value of the boundary indicator is a retransmitted boundary indicator received during good channel conditions; the value of two boundary indicators received successively, both under poor channel conditions, that decode to the same value; or a majority vote of three successive boundary indicators, the first two received under poor channel conditions. The accuracy of the received boundary indicator is increased, at a cost of one, or at most, two, retransmissions. | 03-19-2009 |
20090074047 | APPARATUS AND METHOD FOR ESTIMATING SIGNAL TO INTERFERENCE AND NOISE RATIO IN A WIRELESS COMMUNICATION SYSTEM - An apparatus and method for estimating a Signal to Interference plus Noise Ratio (SINR) in a wireless communication system are provided. The method includes processing a received signal by Orthogonal Frequency Division Multiplexing (OFDM) demodulation to convert the received signal into frequency-domain data, selecting ranging data from the frequency-domain data, multiplying the selected ranging data by a ranging code to perform code demodulation, calculating at least one norm value and at least one coherent norm value by bundle for the code-demodulated data and estimating an SINR using the calculated at least one norm value and at least one coherent norm value. | 03-19-2009 |
20090086803 | APPARATUS AND METHOD FOR DETECTING SIGNALS IN A COMMUNICATION SYSTEM USING MULTIPLE ANTENNAS - An apparatus and method for detecting a signal in a communication system using multiple antennas are provided. The apparatus includes an optimal orderer for determining an order of signals that are subject to detection, a controller for controlling a parallel successive interference canceller so as to successively detect the signals according to the determined signal detection order, cancel the successively detected signals from a received signal, detect the signals in reverse order of the signal detection order, and cancel the successively detected signals from the received signal, and outputting a last detected signal and the parallel successive interference canceller for successively canceling the detected signals from the received signal according to a control of the controller. Accordingly, the invention provides a signal detection apparatus and method that improve the reliability while reducing the complexity of a communication system using multiple antennas. | 04-02-2009 |
20090092178 | Techniques for Estimating Received Signal Strength and Carrier to Interference and Noise Ratio in OFDM Systems - A technique for determining a received signal strength indicator of a target base station at a subscriber station includes performing a discrete Fourier transform on a received signal to provide a transformed signal. In this case, the transformed signal occupies one or more segments of a channel and the one or more segments each include multiple subcarriers. A shift-n cross-correlation is calculated based on the transformed signal and a preamble sequence of the target base station to provide a coarse received signal strength indicator for the target base station. | 04-09-2009 |
20090092179 | Method and a circuit for estimating the signal quality of a communication channel and a wireless receiving apparatus using the same - A method for estimating the signal quality of a communication channel is disclosed. Firstly, an input signal passes through a match filter at the initial stage of an estimation period. Next, the output of the match filter is calculated to obtain the noise reference value within a pre-determined period. The output value of the match filter and the noise reference value are compared. When the output value of the match filter is larger than the noise reference value, a valid power value is obtained according to the output value of the match filter. The valid power values are accumulated. Finally, a SNR is calculated according to the noise reference value and the accumulated valid power value at the end of the estimation period. Thereby, the signal quality of the wireless communication channel is estimated according to the SNR, and the signal transmission rate is determined. | 04-09-2009 |
20090097535 | MULTI-CHANNEL DATA DETECTION PHASE LOCKED LOOP ERROR COMBINATION LOGIC - Phase-error combination for a multi-channel data detection system with a phase locked loop for each channel, comprises receiving phase error information with respect to each channel; combination logic configured to combine the received phase error information and generate a combined phase error; and a phase-error output configured to apply the combined phase error to at least one channel phase locked loop. Additionally, error signal combination comprises receiving error information of a signal relevant to a phase locked loop with respect to each channel; combination logic configured to combine the received error signal information and generate a combined error signal, weighting the received error signal information from each channel, for example with reliability information. An error compensation output is configured to apply the combined, weighted error signal to at least one channel phase locked loop. | 04-16-2009 |
20090097536 | MULTI-CHANNEL DATA DETECTION PHASE LOCKED LOOP FREQUENCY ERROR COMBINATION LOGIC - Frequency error combination for a multi-channel data detection system with a phase locked loop for each channel, comprises receiving frequency error information with respect to each channel; combination logic configured to combine the received frequency error information and generate a combined phase error, weighting the received frequency error information from each channel; and a frequency error output configured to apply the combined frequency error to at least one channel phase locked loop. | 04-16-2009 |
20090103598 | Link adaptation in wireless networks for throughput maximization under retransmissions - The present invention implements a method and system for dynamically adapting the modulation and coding scheme for radio links in a wireless communications network based on a retransmission environment model in order to maximize throughput and most efficiently allocate bandwidth resources. The present invention encompasses a refined calculus and methodology for deriving the link adaptation thresholds in a retransmission environment using a complex model and analysis of the retransmission environment. The present invention holds particular application for wireless data communications as opposed to real time data services because it is based on a retransmission model applicable primarily for data services. A critical component of this new link adaptation system is a “no transmission” cutoff mode that is selected for SIR below a base threshold value. This new mode prevents system instability and misallocation of bandwidth in a wireless communication system. | 04-23-2009 |
20090116543 | SYNCHRONIZATION OF SATELLITE AND TERRESTRIAL BROADCAST ODFM SIGNALS - Synchronization of satellite and terrestrial broadcasts in a shared frequency arrangement is use in order to facilitate simultaneous reception of the broadcasts. A delay value is adjusted based on a synchronization between a first terrestrial broadcast and a satellite broadcast, and a delay value for a second terrestrial broadcast is adjusted based on a synchronization between the second terrestrial broadcast, the first terrestrial broadcast and the satellite broadcast. The adjustment of the relative delay values provides an improved reception pattern based on receipt of a shared frequency communication from multiple sources by improving a signal quality factor within at least selected regions of the coverage areas in which the relative delay values permit synchronization. This allows for synchronization lock between multiple substantially simultaneous broadcasts as determined by a cyclic prefix window of the broadcasts in overlapping coverage areas, useful for simultaneous satellite and terrestrial broadcasts using an OFDM format. | 05-07-2009 |
20090116544 | Performance-based link adaptation techniques using throughput indicator - A multiple carrier wireless communications system includes a channel predictor, a performance predictor, and a link adapter. The channel predictor predicts channel state information for a next packet based on channel state information for the current packet. The performance predictor includes an uncoded performance predictor to predict system performance at a decoder input based on a modulation type and the predicted channel state information for the next packet, and a decoder input-output performance mapper to predict system performance at a decoder output based on a coding rate and the predicted system performance at the decoder input. The link adapter includes a link throughput controller to generate a throughput indicator based on a requested system performance and the predicted system performance at the decoder output, and a modulation and coding scheme (MCS) updater to identify a MCS based on the throughput indicator. | 05-07-2009 |
20090129453 | METHOD FOR IDENTIFYING NOISE SOURCES FOR AUTOMATION DEVICES, AND NOISE SOURCE IDENTIFICATION UNIT THEREFORE - A method for identifying noise sources for automation devices ( | 05-21-2009 |
20090129454 | RATE SELECTION WITH MARGIN SHARING - Rate selection with margin sharing in a system with independent data stream rates is presented. Signal-to-Noise Ratio (SNR) estimates are obtained for each stream. Rates are selected for the streams based on the SNR estimates, such that at least one data stream has an SNR margin below a threshold, each remaining data stream has an SNR margin above a respective threshold, and the total SNR margin for all streams is above a total threshold. For rate selection with margin sharing with a vector-quantized rate set, SNR estimates are obtained for usable transmission channels. The total SNR margin is determined for each rate combination based on the estimates. Each rate combination is associated with a specific number of data streams to transmit, a specific rate for each data stream, and a specific overall throughput. The combination with the highest overall throughput and non-negative total SNR margin is selected. | 05-21-2009 |
20090135892 | APPARATUS AND METHOD FOR MEASURING CARRIER-TO-INTERFERENCE-AND-NOISE RATIO OF LOGICAL BAND USING DOWNLINK PREAMBLE - Provided are an apparatus and method for measuring a carrier-to-interference-and-noise ratio (CINR) using down-link preambles. More particularly, provided are an apparatus and method that measure CINRs according to a plurality of logical bands in a downlink band-adaptive modulation and coding (AMC) channel mode zone using preambles and determine whether or not to switch to another channel mode or logical band on the basis of the CINRS. According to the apparatus and method, it is possible to easily measure a plurality of CINRs and switch to a better channel mode or another logical band using the measured CINRs. Consequently, the optimum channel environment can be maintained. | 05-28-2009 |
20090135893 | Method and System for Weight Determination in a Spatial Multiplexing MIMO System for WCDMA/HSDPA - Certain aspects of the method may comprise generating models for a received plurality of spatially multiplexed communication signals for multiple channels from a plurality of transmit antennas. A calculated signal to noise ratio (SNR) of each multiple channel may be maximized based on the generated models. A phase and an amplitude of at least a portion of the received plurality of spatially multiplexed communication signals may be adjusted based on a plurality of amplitude and phase correction weights determined from the maximized SNR. | 05-28-2009 |
20090141786 | APPARATUS AND METHOD OF ESTIMATING SIGNAL-TO-NOISE RATIO - The present invention relates an apparatus and method of estimating a signal-to-noise ratio (SNR) of a received signal when the received signal has a timing offset. An apparatus for estimating a signal-to-noise ratio (SNR) according to an exemplary embodiment of the present invention includes a fast Fourier transform (FFT) unit that performs a fast Fourier transform on a received signal to convert the received signal into a frequency domain signal; a preamble selector that extracts a preamble from the frequency domain signal; a correlator that correlates the preamble to a preamble reference signal generated by a receiver to calculate a correlation value; an entire power estimator that calculates entire power; a noise power estimator that applies a differential demodulation method to the correlation value to remove a timing offset and calculate noise power; and an estimating unit that uses the entire power and the noise power to estimate the signal-to-noise ratio (SNR). | 06-04-2009 |
20090154540 | METHOD AND APPARATUS FOR ESTIMATING CHANNEL IN MOBILE COMMUNICATION NETWORK - The present invention relates to a method and apparatus for estimating a channel in a mobile communication network. In particular, the present invention relates to a method of estimating a channel under a channel environment where interference between neighboring base stations exists in a mobile communication network using an orthogonal frequency division multiplexing (OFDM) method. In order to estimate a channel, one cluster is divided into two sub-clusters, and pilot sub-carrier signals included in at least one sub-cluster in an OFDM symbol direction are used. Therefore, it is possible to further improve performance as compared to a method of estimating a channel by using pilot sub-carriers included in one cluster. | 06-18-2009 |
20090161745 | Parameter Estimation for Modulated Signals - A system includes a receiver for receiving a modulated signal. The receiver includes a gain estimator for converting complex data representative of constellation points of the modulated signal into scalar data representation. The gain estimator is configured to fold a first portion of the scalar data representation onto a second portion of the scalar data representation. The gain estimator is further configured to estimate a constellation gain value from the folded first portion and the second portion of the scalar data representation. | 06-25-2009 |
20090168861 | Link Supportability In A WCDMA Communications System - A method, computer program product, and system are provided for computing link supportability in a WCDMA communications system. For example, the method can be used to calculate link supportability of a transponder in satellite communications system (e.g. MUOS) in a user-to-base direction. This method can include expressing a carrier signal to noise ratio spectral density for a communication link of interest in terms of a transponder input power of the communication link of interest, a spectral overlap factor representative of one or more interfering communication links, and a transponder input power of the one or more interfering communication links. Assumptions and approximations can be made to simplify the spectral density expression in order to reduce a dimensionality of terms used in the computation of the expression. As such, in reducing dimensionality, the expression becomes a manageable computation for WCDMA communication systems to evaluate. | 07-02-2009 |
20090201980 | METHOD AND DEVICE FOR ESTIMATING A GAUSSIAN WHITE NOISE POWER IN A CHANNEL, AND RECEIVER - A method and device for estimating a Gaussian white noise power in a channel and a receiver are provided. The method includes performing a multi-path search on a received signal to find out paths of the signal; performing a noise estimation on one of the paths to acquire a total noise power of the path; performing an inter-path interference noise estimation on N paths spaced apart from the path by an integral number of chips to obtain an inter-path interference noise power of a single path of the signal, where N is an integer greater than or equal to 1; and subtracting the inter-path interference noise power from the total noise power to obtain the Gaussian white noise power. Through the technical solution of the disclosure, the Gaussian white noise power in a channel is obtained with a higher accuracy, so that the performance of equalization is enhanced. | 08-13-2009 |
20090213919 | SIGNAL QUALITY ESTIMATION FOR OFDMA SYSTEMS - Certain embodiments utilize raw signals to estimate channel quality, as contrasted to utilizing equalized signals or after channel estimation. For example, signal quality may be estimated by calculating powers of pilot sub-carriers and null sub-carriers of the raw signals. To mitigate channel effect, certain embodiments utilize first and/or second order differentiation schemes. | 08-27-2009 |
20090232194 | ADAPTIVE RADIO/MODULATION APPARATUS, RECEIVER APPARATUS, WIRELESS COMMUNICATION SYSTEM, AND WIRELESS COMMUNICATION METHOD - Adaptive modulation part ( | 09-17-2009 |
20090238255 | Estimation of Error Propagation Probability to Improve Performance of Decision-Feedback Based Systems - A decision feedback-based communication system comprising a unit for computing an estimated Error Propagation Probability (EPP) for a plurality of received signals, and a unit for receiving the EPP estimation and improving detected signal quality based thereon. The system can be a coded system or an uncoded system. | 09-24-2009 |
20090245340 | Systems and Methods for Signaling for Vectoring of DSL Systems - The measurement of far-end crosstalk (FEXT) in a Digital Subscriber Line communications is instrumental in the ability of using a multiple input multiple output (MIMO) pre-coder to cancel FEXT. A reliable robust back channel for transmission of error is instrumental to provide error samples for the proper operation of a MIMO pre-coder. Bins can be dedicated to insure bandwidth from the customer premises equipment (CPE) to the central office (CO). By increasing the margin used in the bins, robustness can be added to this back channel between the CPE and CO. | 10-01-2009 |
20090262793 | Noise performance by grouping users according to signal strength or modulation and coding scheme (MCS) - Insight and rules are needed for how to handle scheduling in a way meaningful for network operation is explained, such as what transmissions can be delayed for scheduling and which cannot be delayed for scheduling, and how grouped transmissions can be used for interference avoidance. Certain embodiments of the present invention provide a solution to these and other problems. In certain embodiments of the present invention, for example, users are grouped according to criteria which may be indirectly related to interference but are nevertheless different from interference. Thus, for example, certain embodiments of the present invention use expected receive or transmit signal strength or use MCS as grouping criteria. | 10-22-2009 |
20090279596 | Method for encoding frame data - In applications where data is transmitted in frames of symbols and the transmission medium is such that the probability of correct reception of symbols is, on the average, not uniform for different symbols in a frame, transmission of test frames enables creation of information about the different probabilities of correct reception, and that information is employed by the transmitter to control the manner in which symbols are transmitted so as to ameliorate the effects of the different probabilities of correct reception. | 11-12-2009 |
20090316766 | METHOD OF DETERMINING A CHANNEL QUALITY AND MODEM - Data transmission is disclosed over a transmission channel that is subject to narrowband interferers. An increased overall bit or data transmission rate is achieved by an exemplary method of determining a channel capacity of plural sub-channels of the transmission channel based on a net background noise power estimation. The net background noise power contains only white noise-like contributions and excludes, to a reasonable extent, noise contributions or signal power from narrowband interferers. Hence, the net background noise power can be reduced. For example, an Orthogonal Frequency Division Multiplex (OFDM) signal code construction or bit allocation scheme can be chosen that provides for optimized data transmission at a data rate that approximates or approaches the more realistic channel capacity of an individual sub-channel, resulting in an increased overall bit or data transmission rate. | 12-24-2009 |
20100002758 | ADJUSTABLE TRANSMITTER POWER FOR HIGH SPEED LINKS WITH CONSTANT BIT ERROR RATE - A method and apparatus for dynamically adjusting power of a transmitter is herein described. A transmitter transmits a pattern to a receiver at a differential voltage. The length of the pattern, in one embodiment, is selected to be a reasonable length training pattern, as not to incur an extremely long training phase. If errors are detected at the receiver in the pattern, the transmitter steps the differential voltage until errors are not detected in the pattern at the receiver. The differential voltage, where no errors are detected, is scaled by a proportion of a target confidence level to a measured confidence level associated with the reasonable length training pattern. As a result, a training phase is potentially reduced and power is saved while not sacrificing confidence levels in error rates in the data exchange between the transmitter and receiver. | 01-07-2010 |
20100002759 | LOW BIAS ESTIMATION OF SMALL SIGNAL-TO-NOISE RATIO - A method implemented by a user equipment includes selecting a first estimate of a signal-to-noise (SNR) ratio, calculating a first amplitude and first noise variance, calculating a second amplitude and a second noise variance, calculating a second SNR, calculating a resolution value, adjusting the first SNR, and performing estimation iterations until the resolution value is equal to a predetermined value. | 01-07-2010 |
20100014571 | ASSESSING AIRCRAFT INTERFERENCE PATH LOSS EMPLOYING DISCRETE FREQUENCY STIRRING - A method for accessing aircraft interference path loss in an aircraft. A plurality of radio frequency signals that are stepped through a plurality of frequencies in a frequency range is transmitted from a plurality of locations within an interior of the aircraft. Radio frequency signals present at a receive antenna are received in response to transmitting the plurality of radio frequency signals to form a plurality of measurements. An average of averages curve is generated from the plurality of measurements. A peak to average ratio is identified. Field uniformity is identified. A standard error for the average of averages curve is determined. An upper bound for the aircraft interference path loss in the aircraft is predicted using the average of averages curve, the peak to average ration, the field uniformity, and the standard error. | 01-21-2010 |
20100020859 | SIGNAL TRANSMISSION APPARATUS AND SIGNAL TRANSMISSION CONTROL METHOD - A signal transmission apparatus comprises a first signal transmission section configured to transmit a first signal for performing measurement of characteristics of a transmission line to the transmission line. A reflection characteristic measurement section is configured to measure a reflection characteristic of the transmission line. A pass characteristic measurement section is configured to measure a pass characteristic of the transmission line. A determination section is configured to determine a transmission clock frequency based upon the reflection characteristic. A second signal transmission section is configured to modulate information and to transmit a second signal obtained by the modulation to the transmission line. A second signal receiving section is configured to receive and to demodulate the second signal which has been transmitted by the second signal transmission section and has passed the transmission line. | 01-28-2010 |
20100034249 | FEXT estimation and signaling in Vector Transmission - Embodiments related to FEXT estimation and signaling in vectored systems are described and depicted herein. | 02-11-2010 |
20100046596 | RADIO COMMUNICATION SYSTEM - A radio communication system minimizes power consumption against noises. The system includes a first radio terminal ( | 02-25-2010 |
20100054319 | OFDM WIRELESS MOBILE COMMUNICATION SYSTEM AND METHOD FOR ESTIMATING SNR OF CHANNEL THEREOF - In a method for estimating a signal-to-noise ratio (SNR) of an orthogonal frequency division multiplexing (OFDM) wireless mobile communication system, noise is estimated from adjacent received signals of at least two adjacent subcarriers and received signals of subcarriers, noise power is calculated by calculating a mean square value of the estimated noise by summing squares of the estimated noise, a mean square value of the received signals is calculated by summing squares of the received signals, signal power is calculated by subtracting the noise power from the mean square value of the received signals, and the SNR is calculated using the signal power and the noise power. Thus, the method of the present invention having low complexity can estimate an SNR efficiently regardless of channel changes on a frequency axis when one OFDM symbol includes preamble data. | 03-04-2010 |
20100061436 | SIGNAL MODULATION APPARATUS, SIGNAL MODULATION METHOD, AND COMPUTER PROGRAM PRODUCT - A signal modulation apparatus, a signal modulation method and a computer program product thereof are provided. The signal modulation apparatus is used in a communication framework consisting of a plurality of communication systems. The communication systems comprise a first communication system having a first antenna and a second communication system having a second antenna. The signal modulation apparatus is configured to generate isolation information to modulate a power of a first antenna according to specification information of the first communication system, specification information of the second communication system, information of the first antenna, information of the second antenna, distance information of the first antenna and the second antenna, and test information. | 03-11-2010 |
20100061437 | Systems and Methods for Impulse Noise Characterization - Impulse noise from nearby or intense electrical sources can disrupt communications over digital subscriber lines (DSL). The characterization of the nature, timing and length of impulse noise sources present on a DSL loop is a critical first step in mitigating the effect of impulse noise on DSL communications. DSL standards provide histograms for impulse length and inter-arrival time of impulses. These histograms can be used to derive the nature, maximum frequency and other statistics related to impulse noise on a DSL line. | 03-11-2010 |
20100061438 | METHOD FOR SELECTING TRANSMISSION PARAMETERS FOR A DATA TRANSMISSION AND DATA TRANSMISSION CONTROLLER - A method for selecting transmission parameters for a data transmission is provided comprising determining, for each of a plurality of transmission parameter settings, a data throughput that is expected when the transmission parameter setting is used for data transmission, wherein the data throughput is determined using a pre-generated mapping of transmission parameter settings to data throughputs and selecting a transmission parameter setting based on the determined expected data throughputs. | 03-11-2010 |
20100067568 | SERVICE IN COMMUNICATION SYSTEMS - A method and apparatus for improving performance in communication systems is provided. In one implementation, initial encoded data that has been encoded with a rateless code is received. A quality metric is determined for a communication medium on which the initial encoded data has been received. A modulation scheme used in sending the initial encoded data on the communication medium is identified. An estimate is determined, based on the identified modulation scheme and the determined quality metric, of an amount of mutual information being received per unit of received encoded data. An amount of mutual information being received is determined, based on the determined estimate. | 03-18-2010 |
20100067569 | METHOD OF MONITORING CIRCUIT QUALITY AND CIRCUIT THEREFOR - In a digital wireless communication device having an error correction function, the circuit quality is quickly detected with maintained accuracy. The circuit quality to such an extent that a bit error rate (BER) is slightly degraded (10 | 03-18-2010 |
20100074315 | NOISE SAMPLING DETECTORS - A noise sampling detector suitable for portable electronic devices is disclosed. The detector may detect noise, transmitter signals, spurs, and/or interference. In one embodiment, a detector can include: a load portion; an antenna pattern shaping portion coupled to the load portion, where the antenna pattern shaping portion includes meandering segments of variable lengths and/or widths; and an impedance matching circuit coupled to the antenna pattern shaping portion. | 03-25-2010 |
20100086016 | METHOD AND APPARATUS FOR VARYING A DYNAMIC RANGE - A communications device comprises a receiver for receiving an input signal operably coupled to analogue to digital converter logic. The analogue to digital converter logic is operably coupled to control logic via a signal analyser arranged to analyse a converted received input signal, output from the analogue to digital converter logic to determine at least one characteristic of the received signal. The control logic is arranged to vary a dynamic range of the analogue to digital converter logic depending on the at least one determined characteristic of the received input signal. | 04-08-2010 |
20100128769 | NOISE ESTIMATION APPARATUS AND RELATED METHOD THEREOF - A noise estimation apparatus and method thereof includes an evaluation circuit, a first calculation circuit, a second calculation circuit, and a mean calculation circuit. The evaluation circuit is utilized for determining which constellation point on a constellation diagram each received symbol in a communication signal corresponds to for purposes of generating a relevant evaluated symbol and outputting an evaluated signal. The first calculation circuit is for generating an error output signal according to the communication signal and the evaluated signal, wherein the error output signal includes a plurality of error calculation values. The second calculation circuit is utilized for adjusting at least a portion of the plurality of error calculation values of the error output signal in order to output an adjusted error output signal. The mean calculation circuit is utilized for averaging the adjusted error output signal in order to generate a noise estimation result. | 05-27-2010 |
20100135374 | METHOD AND DEVICE FOR CROSSTALK EVALUATION AND COMMUNICATION SYSTEM COMPRISING SUCH DEVICE - A method and a device are provided for crosstalk evaluation of a channel, wherein the channel is represented and/or modeled by a multiple-input-multiple-output (MIMO) system connecting a first network component with at least one second network component. The MIMO system contains first coefficients associated with transmission lines that are in particular associated with crosstalk. The crosstalk contains a near-end crosstalk (NEXT) portion and a far-end crosstalk (FEXT) portion. The first network component sends a signal to one second network component; the far-end crosstalk portion and the near end crosstalk portion are evaluated. | 06-03-2010 |
20100142603 | Testing of Elements Used in Communication Links - A receiver for a communications link includes a receiver module and a host receiver. These two components can be tested independently. In one embodiment, the receiver module is characterized with respect to noise and distortion. The noise performance can be determined by comparing input and output signals of the receiver module, to determine the relative noise of the receiver module. The distortion performance can be determined by comparing the distortion of input and output signals of the receiver module, using a reference host receiver that includes an equalizer. The host receiver can be tested by using a reference receiver module. | 06-10-2010 |
20100158093 | Methods and System for Determining a Dominant Impairment of an Impaired Communication Channel - Methods are described for identifying a dominant impairment on a communication channel impaired by an interference issue. The methods include systematic examination of total power loading, systematic examination of signal power reduction, statistical examination of communication channel noise power, and systematic examination of interleaver effectiveness. Each relates to automatically diagnosing and characterizing distortion-based interference issues by monitoring the performance of a communication channel during a testing procedure. These methods enable a technician or engineer to remotely diagnose distortion-based interference issues relatively quickly without having to use external test equipment and without having to deploy technicians to various locations within the cable plant. A system by which these methods can be implemented is also disclosed. | 06-24-2010 |
20100195707 | MOBILE STATION DEVICE - A mobile terminal device for performing multi-carrier communication with a base station device can improve communication quality while reducing the data amount without lowering accuracy of feedback information. In the mobile station device ( | 08-05-2010 |
20100202503 | Method and Apparatus for Determing a Quantized Channel Vector - A method for determining a quantized channel vector in a terminal of a Multiple Input Multiple Output communication system includes determining a channel quality of a channel between a base station and the terminal and determining the quantized channel vector from a plurality of quantized channel vectors based on the determined channel quality. The determined quantized channel vector provides a predefined channel property value. | 08-12-2010 |
20100208785 | Method for Determining Automatically a Fext/Next Transfer-Function - A method of automatically determining a far-end crosstalk (FEXT) and near-end crosstalk (NEXT) transfer function in communication lines such as Digital Subscriber Lines (DSL). In a first phase, an input test signal with a known power density spectrum (PSD) covering a frequency range of interest is transmitted at the near end of line A while a received signal or noise-related quantity or PSD is measured at both the near end and far end of line B. In a second phase, transmission of the test signal is stopped, and a received signal or noise-related quantity or PSD is again measured at both ends of line B. In a third phase, the FEXT/NEXT transfer function is determined based on the measurements of the first and second phases. | 08-19-2010 |
20100232490 | METHOD AND APPARATUS FOR COMPENSATING A MODULATION IMBALANCE EFFECT IN A COMMUNICATION DEVICE - A method and apparatus for compensating a modulation imbalance effect in a communication device. In one embodiment, at least three sets of modulation imbalance parameters (MIPs) are estimated by executing an auto balance sequence. The at least three sets of MIPs correspond to a baseband signal configured to have at least three configurable frequencies, each of the at least three sets of MIPs corresponds to one of at least three configurable frequencies. The auto balance sequence is configured to provide an offset signal generated within a communication device to trigger generation of each one of the at least three configurable frequencies. The at least three sets of MIPs are filtered to select a filtered set. The modulation imbalance effect is compensated by using the filtered set to reduce distortion of the baseband signal in the communication device. | 09-16-2010 |
20100254445 | PROCESSING TRANSMISSIONS IN A WIRELESS COMMUNICATION SYSTEM - Disclosed herein are methods of processing transmissions in a wireless communication system to detect whether a transmission unit contains transmitted data, systems for processing transmissions in a digital communications system to detect the same, receivers for processing transmissions in a wireless communications system and computer readable media implementing a method for processing the same. In one embodiment, a method of processing transmissions in a wireless communication system to detect whether a transmission unit contains transmitted data includes: generating an averaged function of bit reliability indicators from a plurality of received samples and applying a test to compare an average of ln cos h(·) (natural logarithm of the hyperbolic cosine) values for the reliability indicators, with a factor proportional to an average signal-to-disturbance ratio of the plurality of samples to determine if the transmission unit contains transmitted data. | 10-07-2010 |
20100260249 | METHOD OF EXAMINING ELIGIBILITY OF A MODULATION AND CODING SCHEME FOR A COMMUNICATIONS SYSTEM - A method of examining the eligibility of a modulation and coding scheme includes determining a range of pseudo signal-to-noise ratio (pseudo-SNR) corresponding to a range of packet correct rate (PCR) acceptable for a transmitter, obtaining a first score of a positive acknowledgement (ACK) and a second score of a negative acknowledgement (NACK) according to the range of pseudo-SNR and the range of PCR, applying weighting to a score of a response message, which is one of an ACK message and a NACK message, and a pseudo-SNR corresponding to an immediately preceding response message when receiving the response message, for generating a pseudo-SNR corresponding to the response message, and examining the eligibility of a modulation and coding scheme in use according to the pseudo-SNR corresponding to the response message. | 10-14-2010 |
20100272167 | Method and Apparatus for Simplifying a Probabilistic Rate Adaptation Procedure in a Wireless Communication System - The present invention provides a method for simplifying a probabilistic rate adaptation procedure in a wireless communication system, which comprises calculating a conditional probability density function of SNR of a transmitted signal by the probabilistic rate adaptation procedure, to generate an SNR estimation result, taking logarithm on the SNR estimation result to generate a logarithm result, and partitioning SNR values into a plurality of regions according to the logarithm result, to generate a discrete function from the SNR estimation result. | 10-28-2010 |
20100296565 | Constant False Alarm Rate Robust Adaptive Detection Using the Fast Fourier Transform - A signal detection apparatus includes electronics configured to receive an RF input and to process the RF input applying a decision rule that is a normalized quantity to determine if a man-made signal is present or if only noise is present while achieving a constant false alarm rate. | 11-25-2010 |
20100296566 | METHOD AND APPARATUS FOR DETERMINING A CALIBRATION SIGNAL - Embodiments of a system for determining and optimizing the performance a signaling system are described. During operation, the system captures or measures a single-bit response (SBR) for the signaling system. Next, the system constructs an idealized inter-symbol-interference-free (ISI-free) SBR for the signaling system which is substantially free of inter-symbol-interference (ISI). The system then calculates an ISI-residual from the captured SBR and the idealized ISI-free SBR. Next, the system constructs a calibration bit pattern for the signaling system that is based substantially on the ISI-residual. Finally, the system uses the calibration bit pattern to calibrate, optimize and determine an aspect of the performance of the signaling system. | 11-25-2010 |
20100296567 | Channel-sensitive power control - A communication receiver which applies signal processing for quantitatively estimating receive signal factors such as communication channel quality, signal characteristics, and overall system received bit error rate (BER) or packet error rate (PER) and which applies a general algorithm for mapping these estimated factors to control receiver performance and minimize power consumption. | 11-25-2010 |
20100296568 | METHOD AND APPARATUS TO CANCEL ADDITIVE SINUSOIDAL DISTURBANCES IN OFDM RECEIVERS - Orthogonal frequency division multiplexing (OFDM) has become a popular transmission method for high speed wireless radio transmission, due to its potential for low complexity of transmitters and receivers. A method and apparatus are contemplated for cancelling additive sinusoidal disturbances of a known frequency in OFDM receivers which arise e.g. from clock signals that are present for frequency reference, mixer control, and A/D converter control, as well as harmonics and mixing products of those periodic signals, coupling into some point in the receiver chain and appearing as rotating complex exponentials superimposed to complex baseband receive signals. According to the inventive method and apparatus an estimation of an amplitude and phase of a disturbing superimposed tone with a known frequency is obtained and the amplitude and phase estimation is used to cancel the spurious tone preventing a degradation of receiver sensitivity while achieving low implementation complexity. | 11-25-2010 |
20100303140 | SNR estimation system for multi-carrier communication - A signal to noise power ratio estimation system for multi-carrier communication includes a phase rotator, a power estimator, a channel gain calculator, an average and selection device, a combination and calculation device and a decibel (dB) transformation device. The signal to noise power ratio estimation system makes use of a transmit parameter signaling or pilot subcarriers to blindly assist in the signal to noise power ratio estimation to accordingly gain an estimated signal to noise power ratio accurately, and thus a communication system can be calibrated to a preferred condition. | 12-02-2010 |
20100303141 | APPARATUS AND METHOD FOR RECEIVING SIGNAL USING RAKE RECEIVER AND EQUALIZER IN WIRELESS COMMUNICATION SYSTEM - An apparatus and a method for selecting a receiver for demodulating a reception signal at a reception end having a plurality of receivers are provided. The method includes determining, a mean and a standard deviation of Signal-to-Noise Ratios (SNRs) of the receivers are determined, estimating a Doppler frequency, determining a statistical value of a modulation order of subframes received in advance, determining SNR estimation values of the receivers based on the determined mean and standard deviation of the receivers, the estimated Doppler frequency, and the determined statistical value of the modulation order of the received subframes, selecting one receiver having a largest SNR estimation value among the determined SNRs of the receivers, and demodulating a reception signal using the selected receiver. | 12-02-2010 |
20100322298 | DEVICE FOR EVALUATING SIDE-CHANNEL ATTACK RESISTANCE, METHOD FOR EVALUATING SIDE-CHANNEL ATTACK RESISTANCE, AND PROGRAM FOR EVALUATING SIDE-CHANNEL ATTACK - A side channel attack resistance evaluation apparatus includes: a measurement section that measures side channel information leaking from an encryption device to be evaluated; a noise removal section that removes noise from the measured side channel information using a band-pass filter (BPF); a passband determination section that determines the passband of the band-pass filter; and a DSCA (Differential Side-Channel Analysis) evaluation section that evaluates resistance against the differential side channel analysis. The passband determination section preferably has a DFT processing section and a power spectrum analysis section, or has a DFT processing and a DFA processing section. | 12-23-2010 |
20100329320 | Noise detection method, noise detection apparatus, simulation method, simulation apparatus, and communication system - For voltage values (observed noise sequence) in an electronic power line (communication medium) which are obtained at a predetermined interval, initial values of noise characteristics based on a statistic of the observed noise sequence itself are decided by a moment method (S | 12-30-2010 |
20100329321 | ELECTRONIC DEVICE FOR RECEIVING A RADIO-FREQUENCY SIGNAL - An electronic device includes an analog-to-digital converter adapted to receive a radio-frequency signal and adapted to provide therefrom a digital signal, wherein the radio-frequency signal may include an interference signal. The electronic device has a controller adapted to perform a digital measure on the digital signal and adapted to generate therefrom a selection signal having a first value indicating a non-interference condition in the radio-frequency signal and having a second value indicating an interference-condition in the radio-frequency signal. A selector is adapted to transmit the digital signal in case the selection signal has the first value and to transmit a signal replacing the digital signal in case the selection signal has the second value. | 12-30-2010 |
20110002371 | System and method for adjusting DIDO interference cancellation based on signal strength measurements - A machine-implemented system and method are described for removing interference between adjacent distributed-input-distributed-output (DIDO) clusters comprising. For example, a method according to one embodiment comprises: detecting signal strength at a first client from a main DIDO cluster; detecting interference signal strength at the first client from an interfering DIDO cluster; if the signal strength from the main DIDO cluster reaches a specified value relative to the value of the interference signal strength from the interfering DIDO cluster, then generating channel state information (CSI) defining channel state between one or more antennas of the first client and one or more antennas of the interfering DIDO cluster; transmitting the CSI from the first client to a base transceiver station (BTS) in the interfering DIDO cluster; and implementing DIDO precoding with inter-DIDO-cluster interference (IDCI) cancellation at the BTS in the interfering DIDO cluster to avoid RF interference at the first client. | 01-06-2011 |
20110002372 | DOWNLINK CHANNEL PARAMETERS DETERMINATION FOR A MULTIPLE-INPUT-MULTIPLE-OUTPUT (MIMO) SYSTEM - Embodiments of methods and apparatus for providing downlink channel parameters determination for downlink channels associated with a multiple-input-multiple-output (MIMO) system are generally described herein. Other embodiments may be described and claimed. | 01-06-2011 |
20110007791 | Method for the detection and generation of a useful signal and associated devices and communications system - A method for the generation of a signal including a minimum of disturbances and noise is provided. A method for the detection of a signal including a minimum of disturbances and noise is also provided. An element of the signal is functionally dependent on at least one further element of the signal. | 01-13-2011 |
20110019727 | Method and System for Determining Synchronization Status in a Wide Band CDMA Network - A method and system for determining synchronization status in a wide band CDMA (WCDMA) network may comprise calculating a signal to noise ratio (SNR) of a downlink dedicated physical channel (DPCH) based on a plurality of transmit power control (TPC) bits received via the downlink dedicated physical channel (DPCH), wherein the value of at least one of the plurality of TPC bits is not known when at least one of the plurality of TPC bits is received. The transmit circuitry may be controlled based on the calculated signal to noise ratio. The transmit circuitry may be disabled if the calculated SNR of the plurality of TPC bits is below a first channel threshold. The transmit circuitry may be enabled if the calculated SNR of the plurality of TPC bits is above a second channel threshold. | 01-27-2011 |
20110026574 | SIGNAL AND NOISE POWER ESTIMATION - Techniques for estimating desired signal power and noise power of a signal received over a communications channel. In an aspect, a pilot autocorrelation matrix is derived based on certain assumptions about the time delay profile, Doppler profile, and/or spatial correlation of the channel. The pilot autocorrelation matrix is decomposed into a set of eigenvectors. From the eigenvector decomposition, a set of dominant eigenvectors is selected to estimate the signal power, while a set of non-dominant eigenvectors is selected to estimate the noise power. The techniques may readily be applied to arbitrary pilot patterns and to a wide array of SNR ranges and channel conditions. | 02-03-2011 |
20110026575 | Method and Apparatus For Enhanced Performance and Crosstalk Measurement in a MIMO Communication System - The present invention comprises a system and method for reduction of the influence of crosstalk, increase in and control over quality of service, increase in stability and reduction of power use in a system having multiple transmission lines. A novel crosstalk measurement method is introduced. Knowing the crosstalk, various algorithms may be employed, for example to reduce or eliminate its effects in order to guarantee a bit error rate equal to or less than the maximum allowed for each line. Similar methods are provided to minimize power consumption, or maximize related measures of line performance. Systems, devices, methods and techniques are provided that allow communication system to adapt transmission power margin, power spectral densities, and the like dynamically to changing subscriber's application needs in MIMO systems. | 02-03-2011 |
20110038405 | Communications Unit and Method for Detecting Pulse Interference - A communication method for use in a first cellular communications system is proposed for minimizing the interference caused by strong interfering pulses in the same frequency band as the system or an adjacent frequency band. The method comprises the steps of receiving an incoming signal bandpass filtering the incoming signal to filter out a first frequency band (B | 02-17-2011 |
20110038406 | METHOD AND DIGITAL COMMUNICATION DEVICE FOR RECEIVING DATA USING QAM SYMBOLS - A digital communication system which applies channel coding and QAM modulation, where in QAM, at the transmitter, a number Q of bits is mapped to one QAM symbol, which is transmitted over the channel, at the receiver side, for each QAM symbol, a de-mapping is performed in order to obtain an L-value for each bit which corresponds to the QAM symbol, such that these L-values provide not only an estimation of the transmitted bits but also give information about their reliability | 02-17-2011 |
20110051792 | SIGNAL ANALYZING APPARATUS FOR LTE SYSTEM - A signal analysis apparatus of an LTE system includes a radio frequency reception unit for receiving a radio frequency signal of the LTE system and converting it into a signal of an intermediate frequency, a digital signal conversion unit for converting an analog signal, processed by the radio frequency reception unit, into a digital signal, a baseband conversion unit for converting the signal of the intermediate frequency into a baseband signal, a baseband signal simple analysis unit for decoding the baseband signal in real time in accordance with an LTE standard, a signal depository for storing the baseband signal, a baseband signal precision analysis unit for decoding and analyzing the baseband signal in accordance with the LTE standard and analyzing various items derived in the decoding process, two switching units for alternatively connecting the baseband conversion unit or the signal depository to the baseband signal simple analysis unit or the baseband signal precision analysis unit, and a control unit for controlling the switching units. | 03-03-2011 |
20110069748 | Measuring Bit-Error-Rates of Forward Error Correction Code Encoded Signals - A device may include one or more components and a processor. The one or more components may obtain bit-error-rates of a signal and signal-to-noise ratios of the signal. The processor may select a target signal-to-noise ratio for the signal, determine a target noise level based on the target signal-to-noise ratio, set a noise level of the signal to the target noise level, determine a signal-to-noise ratio of the signal via the one or more components, adjust the noise level of the signal based on the determined signal-to-noise ratio, to stabilize the signal-to-noise ratio, determine a bit-error-rate of the signal via the one or more components, and record the bit-error-rate. | 03-24-2011 |
20110090944 | APPARATUS AND METHOD FOR SIGNAL QUALITY MEASUREMENT ON GFSK SIGNALS - The present invention discloses an effective apparatus and method to measure the received signal quality for a GFSK modulated signal with (or without) an unknown modulation index. The signal quality measurements are based on the decoded (unknown or known) bits and the trellis of the frequency discriminator output. This trellis is pre-calibrated with a reference Rx. The transmitted modulation index is also accurately estimated in this invention. | 04-21-2011 |
20110090945 | METHOD AND APPARATUS FOR COOPERATIVE MIMO TRANSMISSION OPERATION IN MULTICELL WIRELESS NETWORK - A method and apparatus of configuring a multi-cell precoding matrix for a multiple input multiple output (MIMO) operation in a wireless communication system in which a plurality of base stations participate in cooperative communication is provided. A multi-cell precoding matrix is configured using one or more single-cell precoding matrices, and wherein coefficients to be multiplied by the single-cell precoding matrices satisfy a condition in which the product between the multi-cell precoding matrix and a Hermitian matrix of the multi-cell precoding matrix is a unitary matrix. According to the embodiment of the present invention, it is not necessary for all base stations to perfectly know channel information. In addition, a feedback overhead is not high, and complexity is low. | 04-21-2011 |
20110110414 | MULTICELLULAR COOPERATIVE COMMUNICATIONS IN A DECENTRALIZED NETWORK - In a multicellular cooperative radio communications method, the terminals estimate and communicate to all the access points of a cooperating cluster of access points information on the transmission channels between them and each access point of the cluster. The access points include homologous processor for scheduling the servicing of the terminals and operating in accordance with a particular criterion common to all the access points. Finally, the servicing of the terminals is effected jointly by said access points, in an order determined by the processor, using transmission parameters on the basis of the information on the transmission channels transmitted by the terminals. | 05-12-2011 |
20110122937 | METHOD AND DEVICE FOR SNR MEASUREMENT AND COMMUNICATION SYSTEM COMPRISING SUCH DEVICE - A method and a device enable signal-to-noise (SNR) measurement. The system includes the following steps: (i) at least one first network component transmits bursts to at least one second network component, wherein each burst comprises several sub-carriers or tones; and (ii) a third network component performs an SNR measurement for the bursts. In addition, a communication system with such a device is described. | 05-26-2011 |
20110129009 | METHOD AND SYSTEM FOR EFFICIENT CHANNEL ESTIMATION - Aspects of the present disclosure describe an efficient channel estimation algorithm for high-speed processing of dedicated reference signals. The channel estimation algorithm may utilize one or more compressed interpolation matrices. The compressed interpolation matrices may be selected based on the Doppler value and signal to noise ratio (SNR) of the channel. | 06-02-2011 |
20110142115 | METHOD AND APPARATUS THAT FACILITATES ESTIMATING DOPPLER SPREAD FOR UPLINK TRANSMISSIONS - Methods, apparatuses, and computer program products are disclosed for performing a Doppler spread estimation. In a first embodiment, an energy associated with a communication from a wireless terminal is ascertained based on at least one pilot symbol and at least one data symbol. Each of an energy variance and a noise variance are then determined to facilitate estimating a speed of the wireless terminal based on the energy variance normalized by the noise variance. In another embodiment, a signal received from a wireless terminal is decoded and replicated. A channel estimate associated with a set of data symbols is then ascertained from the replica, which is used to estimate the speed of the wireless terminal. | 06-16-2011 |
20110142116 | METHOD AND APPARATUS FOR ESTIMATING CHANNEL PARAMETER - A method and apparatus for estimating a channel parameter in a multi-antenna system is provided. The method of estimating a channel parameter includes selecting at least a part of received data as an effective segment based on power of the received data, and estimating a channel parameter by applying a channel estimation algorithm to received data within the selected effective segment. Accordingly, it is possible to reduce the amount of calculation by removing noise signals from received data and measuring channels using signals within an effective signal segment when the channel parameters are estimated. | 06-16-2011 |
20110142117 | SIGNAL DETECTING METHOD AND DEVICE FOR MULTI-CODEWORD MIMO SYSTEM - A signal detecting method and device for a multi-codeword multi-input multi-output (MIMO) system are provided, which are used in the field of communication and solve the problem that it is complex to implement a signal detecting method in the multi-codeword MIMO system and the error between the signal obtained through detection and the signal actually transmitted from the transmitting end is large. The method includes: converting a received complex number signal into a real number signal; performing channel estimation to obtain a channel matrix; correcting the channel matrix to obtain an equivalent corrected matrix; generating an equivalent detecting signal according to the equivalent corrected matrix and the real number signal obtained through conversion; quantizing the equivalent detecting signal to obtain an equivalent quantized detecting signal; and generating a signal transmitted from a transmitting end according to the equivalent quantized detecting signal. The method and device can be applied in a receiving device of a multi-codeword MIMO system. | 06-16-2011 |
20110150067 | Echo canceller for eliminating echo without being affected by noise - In an echo canceller, a specific frequency component eliminator eliminates a specific frequency component of a specific frequency from a receiver signal to output a resultant signal to an echo path. A specific frequency component detector detects a frequency component of the same frequency as the specific frequency eliminated by the specific frequency component eliminator from the transmitter signal. A noise calculator finds noise power on the basis of power of the specific frequency component detected by the specific frequency component detector, and finds total power including noise and an echo component on the basis of power of a frequency component including the echo component. A control parameter calculator uses the noise power and the total power found by the noise calculator to find a control parameter of the echo canceller. | 06-23-2011 |
20110158304 | TECHNIQUES TO CONTROL UPLINK POWER - Techniques are described that provide uplink power control techniques that can support different uplink multi-input multi-output (MIMO) transmission schemes. A mobile station determines a Signal to Interference-plus-Noise Ratio based on base and offset values transmitted from a base station. The base station can transmit the base and offset values using seven bits total. The mobile station determines an uplink transmitter power level based on the Signal to Interference-plus-Noise Ratio. | 06-30-2011 |
20110158305 | Reporting Channel Quality Information for Multiple Channels - Aspect of the invention relate to a method for reporting channel quality information from a user equipment (UE) to a base station. In some embodiments, the method includes: determining a first channel quality value (CQ | 06-30-2011 |
20110164669 | Systems and Methods for Determining Noise Components in a Signal Set - Various embodiments of the present invention provide systems and methods for estimating noise components in a received signal set. For example, one embodiment of the present invention provides a noise estimation circuit that includes a data detector circuit and a noise component calculation circuit. The data detector circuit receives a series of data samples and provides a detected output, and the noise component calculation circuit provides an electronics noise power output and a media noise power output each calculated based at least in part on the detected output and the series of data samples. | 07-07-2011 |
20110164670 | POWER LINE COMMUNICATION SYSTEM - The present invention relates to a communication system comprising a transmitter and receiver in communication for transmitting signals through one or more communications channels, wherein at least one of the transmitter and the receiver each comprise a quality measure, which contributes to an overall quality measure for the system and wherein the or each communications channel comprises a plurality of sub-bands between at least two nodes, wherein the plurality of sub-bands each having a specific maximum power spectral densities (PSDs) and wherein one or more sub-bands between the transmitter and the receiver are identified as having a higher maximum PSD than other sub-bandsand wherein the PSD of the one or more identified sub-bands is reduced in a predetermined manner to thereby increase the overall quality measure for the system. | 07-07-2011 |
20110170586 | APPARATUS AND METHOD FOR PREDICTING SINR IN SPATIALLY MULTIPLEXED MULTIPLE INPUT MULTIPLE OUTPUT SYSTEM - A receiver of a spatially multiplexed multiple input multiple output (SM MIMO) system divides the SM MIMO system into a plurality of virtual single input multiple output (SIMO) systems by using the estimated channel, calculates losses generated by the plurality of streams received through the plurality of reception antennas, and predicts an SINR of each stream by using the losses and the capacities of the plurality of virtual SIMO systems. It is possible to more accurately estimate the performance of a maximum likelihood (ML) detector or the performance of a detector showing the performance of a maximum likelihood (ML) detection mechanism by using the estimated SINR of each stream. | 07-14-2011 |
20110176598 | NETWORK EVENT DETECTION - Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for identifying network events. In one aspect, a method includes monitoring signal characteristic values for signals transmitted over a communications channel of a power line communications system and determining that a signal level value for the channel is less than a threshold signal level value for the channel. In response to determining that the signal level value for the channel is less than the threshold signal level value for the channel, computing a signal to noise ratio for the communications channel and determining that the signal to noise ratio for the channel exceeds a threshold value. In response to determining that the signal to noise ratio for the communications channel exceeds the threshold value, storing data received over the communications channel as valid data. | 07-21-2011 |
20110176599 | Rate-Adaptive Multiple Input/Multiple Output (MIMO) Systems - A rate-adaptive method of communicating over a multipath wireless communication system uses multiple links such that each end of a link uses multiple transmit and receive antennas. A number of independent streams that are to be transmitted for each link is determined based on an overall system performance measure. In addition, the system may also jointly determine the best modulation, coding, power control, and frequency assignment for each link, based on an overall system performance measure. In OFDM systems, the number of independent streams, as well as the modulation, coding, and power control, may be determined on a tone-by-tone basis based on an overall system performance measure. | 07-21-2011 |
20110182345 | METHOD AND APPARATUS FOR ADAPTING A BIT INTERLEAVER TO LDPC CODES AND MODULATIONS UNDER AWGN CHANNEL CONDITIONS USING BINARY ERASURE SURROGATE CHANNELS - The present invention relates to code-dependent bit interleavers for parallel non-uniform channels. Since the channel dependence of a given code ensemble is dominated by the mutual information between the channel input and output, the present invention proposes to simplify the analysis about the decoding behavior by using a set of surrogate binary erasure channels. The approximation of the actual channel by the surrogate BEC is established on the equivalence of bitwise capacities, which represent the mutual information between the uniformly-distributed binary input and the likelihood ratios of the effective parallel AWGN channels. Moreover, the transition of the erasure probabilities is modeled by a linear difference equation around the decoding threshold SNR, from which we can derive a necessary condition on the convergence of decoding iterations and achieve a useful guideline for the configuration of the bit interleaver. | 07-28-2011 |
20110182346 | APPARATUS AND METHOD FOR ESTIMATING NOISE AND INTERFERENCE POWER IN COMMUNICATION SYSTEM - An apparatus and a method for estimating a Noise and Interference (NI) power in a communication system are provided. The method includes, calculating average values of impulse responses according to ranging codes, through use of a ranging signal sequence received through a resource allocated to a ranging channel, arranging the average values of the impulse responses according to ranging codes in order of the highest value to the lowest value, and multiplying a ranging code, which corresponds to an impulse response having an (x+1) | 07-28-2011 |
20110188560 | Matching Pursuits Basis Selection - A method, apparatus, and computer-readable medium for basis selection is described. A plurality of sub-bands of digital data is generated and a basis function for the digital data in one of the plurality of sub-bands is determined at a rate that provides a substantially peak signal-to-noise ratio for the digital data. The basis function is added to a codebook and the digital data is compressed using the codebook. | 08-04-2011 |
20110188561 | SNR ESTIMATION - A method for estimating a Signal to Noise Ratio (SNR) in a received signal including, for a fixed first set of a plurality of samples from the received signal, providing an initial noise estimate, starting with the initial noise estimate, iteratively improving the noise estimate, and estimating SNR based, at least partly, on the fixed first set of samples from the received signal and the noise estimate. Additional related apparatus and methods are also described. | 08-04-2011 |
20110200088 | SERVICE IN COMMUNICATION SYSTEMS - A method and apparatus for improving performance in communication systems is provided. In one implementation, information is accessed indicating the quality of at least one communication channel. Based on the accessed information, a modulation scheme is indicated for sending data over the channel encoded with a rateless code. Various different information relating to the communication channel can be used to determine a quality metric for the channel. | 08-18-2011 |
20110206107 | Blind SIR Estimation Using Soft Bit Values - An SIR estimate of a communication signal in a wireless communication system receiver is calculated based on soft bit values output by a nonlinear detector. The average amplitude of the detector output soft bits is estimated. The average power of the detector output soft bits is estimated, e.g., as a mean-square or variance. An SIR of the communication signal is estimated based on the soft bit amplitude and power estimates. In particular, the SIR is estimated as the ratio of the square of soft bit amplitude to the difference between the mean square soft bit power and the square of soft bit amplitude, or the ratio of the square of soft bit amplitude to the variance. In either case, the SIR estimate may be scaled to obtain the desired units. The communication signal may be a received signal, or a simulated signal generated using channel estimates obtained from, e.g., a pilot channel. | 08-25-2011 |
20110228835 | COMMUNICATION APPARATUS, WIRELESS COMMUNICATION SYSTEM, METHOD FOR APPROXIMATION IN FEEDBACK INFORMATION CALCULATION, AND RECORDING MEDIUM - Provided is a communication apparatus which calculates a CQI indicating reception quality of a reception signal in a receiver and feeds back the CQI to a transmitter, the CQI containing information obtained by averaging SNRs of a plurality of subbands, which are generated by dividing a reception band into a predetermined number, in the reception band, the communication apparatus including a CQI/PMI/RI estimation unit directly uses an initial value in a predetermined approximation method as an approximation calculation result obtained by the predetermined approximation method to thereby simplify the calculation, when the predetermined approximation method is used for calculation in the averaging in place of root calculation and when values of the SNRs are high. | 09-22-2011 |
20110243209 | Method device & system for receiving a communication signal - Disclosed is a receiver, such as an orthogonal frequency-division multiplexing (OFDM) receiver, including two or more receiver chains. Each of the receiver chain may include an antenna, down converting circuitry and time to frequency converting circuitry, and the two or more chains may be adapted to operate in concert so as to receive substantially the same signal substantially concurrently. Signal processing circuitry may be adapted to constructively combine signals received at the two or more receiver chains into a unified signal. Selection logic may be adapted to select a mode of signal combination by the signal processing circuitry, wherein the selection logic may be adapted to instruct the processing circuit to either combine two or more received signals into a single received signal or to use only one of the two or more received signals for further processing. | 10-06-2011 |
20110243210 | APPARATUS AND METHOD FOR POWER SAVING USING REQUANTIZATION IN BASEBAND MODEM - In the power saving, a method for saving power at a receiver of a mobile communication system includes acquiring Carrier to Interference plus Noise Ratio (CINR) and Modulation and Coding Scheme (MCS) information required by the receiver; determining the number of Least Significant Bits (LSBs) to hold based on the CINR and MCS information; and holding LSBs of the determined number of the bits in received information. | 10-06-2011 |
20110261872 | CHANNEL QUALITY ESTIMATION FOR MLSE MIMO RECEIVER - A receive signal processor jointly detects two or more symbols in a signal-of-interest in the presence of one or more other MIMO signals. The signal-to-interference-plus-noise ratio for each signal-of-interest is determined by computing per-subcarrier signal-to-interference-plus-noise ratios for a plurality of subcarriers allocated to the signals-of-interest, and computing a total signal-to-interference-plus-noise ratio for the subcarriers based on the per-subcarrier signal-to-interference-plus-noise ratios of the subcarriers. A controller determines one or more transmission formats for uplink transmissions based on the signal-to-interference-plus-noise ratios. The process of computing per-subcarrier signal-to-interference-plus-noise ratio reflects the amount of MIMO interference already cancelled or still remaining in the signal arriving at the joint detector. | 10-27-2011 |
20110280296 | CHANNEL QUALITY ESTIMATION FROM RAW BIT ERROR RATE - Channel quality metrics (such as SINR, BLER, and the like) are derived from a raw bit error rate (RBER), defined as the error rate of raw bits output by a demodulator. These initial raw bits are decoded and error-checked (or error-corrected). The error-free decoded bits are re-encoded, and the regenerated raw bits are compared to the initial raw bits to determine the RBER. The RBER is then converted to SINR, BLER, or other channel quality metric. The RBER-based metrics are derived from a data channel rather than reference signals, and hence more accurately reflect deviations from nominal transmission power level, and include receiver demodulator impairments. | 11-17-2011 |
20110292988 | CLASSIFICATION OF INTERFERENCE - An interference classifier is disclosed for determining the type of interference present in a signal. The interference classifier | 12-01-2011 |
20110305267 | Precoder for a Communication System and Methods Used in Said Communication System - The present invention relates to a precoder for a communication system arranged to provide transmission blocks for transmission over a transmission channel based on inputted symbol blocks. The precoder is arranged to pre-distort each symbol block based on an estimate of the characteristics of the transmission channel so that the corresponding transmission block appears to be undistorted after transmission over the transmission channel. In accordance therewith, the precoder is arranged to apply Tomlinson-Harashima precoding on a sum of a first measure corresponding to predistortion so as to remove intrasymbol interference and a second measure corresponding to predistortion so as to remove intersymbol interference. The present invention further relates to a method for providing transmission blocks for transmission over a transmission channel in a communication system. | 12-15-2011 |
20110305268 | Method and System and Device for CQI Estimation Disturbance Cancellation - The current invention relates to a method of determining a quality of a received signal, wherein the method comprises receiving a signal comprising a first part and a second part and wherein at least the second part of the received signal comprises a scrambling sequence period; and determining a first noise-and-interference power of the first part of the received signal by removing a second noise-and-interference power of the second part of the signal, wherein the scrambling sequence period is utilized in the removal. The invention further relates to a corresponding device and system. Thereby, the invention is able to, among other things, reduce neighbor cell reference symbol interference in a dense network. | 12-15-2011 |
20120002710 | FIXED STATION RECEIVER FOR MIMO COMMUNICATION SYSTEMAND UPLINK ADAPTATION METHOD THEREOF - Provided are a fixed station receiver for a Multi-Input Multi-Output (MIMO) communication system and an uplink adaptation method thereof. In the uplink adaptation method, a sounding reference signal (SRS) is received from a terminal including a plurality of transmission antennas. A complex channel matrix (H) corresponding to a channel response and a noise variance (σ | 01-05-2012 |
20120020402 | RECEIVER - An embodiment of the invention relates to a method of determining an optimum sequence of algorithms, wherein each algorithm defines a receiver function of a receiver, which has a plurality of receiver functions and which is adapted to receive bits sent by a transmitter. | 01-26-2012 |
20120020403 | MULTI-ANTENNA SCHEDULING SYSTEM AND METHOD - A wireless communication method and system using virtual MIMO (“V-MIMO”) are provided. Post processing signal to interference and noise ratios (“SINR”) for a plurality of signals corresponding to a plurality of mobile terminals arranged as a V-MIMO group are estimated. The one of the plurality of mobile terminals having the highest post processing SINR is selected. Wireless communication for the selected mobile terminal is scheduled. The signal corresponding to the selected mobile terminal is cancelled. Post processing signal to interference and noise ratios (“SINR”) for the signals corresponding to the remaining mobile terminals is re-estimated. The one of the remaining mobile terminals having the highest post processing SINR is selected. Wireless communication for the selected remaining mobile terminal is scheduled. | 01-26-2012 |
20120033721 | Receiver with ICI Noise Estimation - The invention concerns receive circuitry for demodulating an input signal received from a transmission channel, the receive circuitry having a decision feedback equalizer ( | 02-09-2012 |
20120033722 | Time-Domain Link Adaptation - Embodiments of the invention provide time-domain link adaptation in power line communications. In one embodiment, the cyclic prefix length and position is adjusted with an OFDM symbol to overlap a periodic impulse noise pulse, thereby allowing the data carried in the symbol to be detected at a receiver. The cyclic prefix may be adjusted to provide a pattern that yields an integer number of OFDM symbols in one zero crossing period. The data rate used for the symbols overlapping the zero-crossing period may be zero or very low. A high data rate may be used for symbols outside the zero-crossing period because those symbols will not be affected by the periodic impulse noise. | 02-09-2012 |
20120033723 | METHOD, PRE-CODING APPARATUS AND WIRELESS COMMUNICATION SYSTEM FOR MULTIPLE-INPUT MULTIPLE-OUTPUT COLLABORATIVE COMMUNICATION - A method for multiple-input multiple-output (MIMO) collaborative communication in a wireless communication system includes at least one user equipment and M base stations performing collaborative communication with the user equipment. Here, M is an integer that is greater than or equal to 2. The method includes the following processes for each user equipment: a first level of MIMO pre-coding process is performed for each base station to acquire each first level of pre-coding matrix corresponding to each base station; a second level to the X-th level of MIMO pre-coding process is performed sequentially to acquire the second level to the X-th level of pre-coding matrices of the corresponding base stations. Here, X is an integer that is greater than or equal to 2. A pre-coding device, a user equipment and a wireless communication system related to the method are also provided. | 02-09-2012 |
20120069889 | INTERFERER PARAMETER ESTIMATION METHOD AND APPARATUS - Interference is estimated in an Orthogonal Frequency Division Multiplexing system by receiving at a wireless receiver pilot symbols and data symbols transmitted in time and frequency via resource blocks, detecting a first one of the data symbols transmitted to the wireless receiver via a time-frequency resource element of a first one of the resource blocks and identifying a second one of the resource blocks adjacent the first resource block having related interference parameters. The interference is estimated based on the pilot symbols transmitted via the first resource block and the pilot symbols transmitted via the second resource block. | 03-22-2012 |
20120082200 | METHOD AND APPARATUS FOR MEDIUM ACCESS CONTROL IN A WIRELESS BROADBAND SYSTEM WITH MULTIPLE-INPUT MULTIPLE-OUTPUT OR MULTIPLE-INPUT SINGLE-OUTPUT TECHNOLOGY WITH MULTIUSER CAPABILITIES - Method and apparatus for medium access control in a wireless broadband system with multiuser MIMO/MISO technology comprising the steps of a transmitter (Tx) broadcasting a polling message ( | 04-05-2012 |
20120099634 | RECEIVING DEVICE AND METHOD, DEMODULATING DEVICE AND METHOD, AND PROGRAM - The present disclosure provides a receiving device including, a receiver configured to receive a signal that is transmitted via a propagation path and is modulated by a predetermined system prescribed by a predetermined standard, a demodulator configured to demodulate a received signal, an estimator configured to estimate a signal-to-noise ratio relating to the propagation path, obtained from a data signal included in the demodulated received signal, and a corrector configured to correct an estimated signal-to-noise ratio in accordance with a transmission parameter obtained from the received signal. | 04-26-2012 |
20120106612 | METHOD OF EVALUATING THE PROFIT OF A SUBSTREAM OF ENCODED VIDEO DATA, METHOD OF OPERATING SERVERS, SERVERS, NETWORK AND APPARATUS - There is disclosed in aspects of the invention a method of evaluating the profit of a substream of encoded video data, a method of operating servers, a network and an apparatus. In the method, a data portion is identified comprising at least some of the data in the substream being evaluated; comparing a decoded version of the video with the data portion present and a decoded version of the video with the data portion removed and calculating an error metric indicative of the distortion between the two versions; and, calculating a profit for the substream dependent upon the error metric. | 05-03-2012 |
20120106613 | SYSTEMS AND METHODS FOR SELECTING RECONFIGURABLE ANTENNAS IN MIMO SYSTEMS - A method allows reconfigurable multi-element antennas to select the antenna configuration in MIMO, SIMO and MISO communication system. This selection scheme uses spatial correlation, channel reciprocal condition number, delay spread and average Signal to Noise Ratio (SNR) information to select the antenna radiation pattern at the receiver. Using this approach, it is possible to achieve capacity gains in a multi-element reconfigurable antenna system without modifying the data frame of a conventional wireless communication system. The capacity gain achievable with this configuration selection approach is calculated through numerical simulations using reconfigurable circular patch antennas at the receiver of a MIMO system that employs minimum mean square error receivers for channel estimation. Channel capacity and Bit Error Rate (BER) results show the improvement offered relative to a conventional antenna selection technique for reconfigurable MIMO systems. | 05-03-2012 |
20120106614 | SYSTEM AND METHOD FOR CHANNEL INTERPOLATION - A system and method for channel interpolation in a wireless device. In one embodiment a wireless device includes a channel estimator. The channel estimator is configured to generate estimated channel coefficients for a wireless channel over which the wireless device receives a packet. The channel estimator includes an interpolation filter. The interpolation filter is configured to provide interpolated channel coefficients for a plurality of non-pilot sub-carriers. The interpolated channel coefficients are based on pilot sub-carriers of non-preamble symbols. | 05-03-2012 |
20120114030 | Power Scaling for Retransmissions in Uplink MIMO Hybrid ARQ - A method includes obtaining a precoder for retransmission of one codeword responsive to known precoding matrix P of rank r and modulation and coding scheme MCS assignments used in an original transmission, and a desired retransmission rank r′; and scaling power in the retransmission responsive to at least two of 1) information parameters Index of UL precoder in previous transmission, 2) rank r of uplink UL precoder in previous transmission, 3) MCS assignments in previous retransmission (MCS | 05-10-2012 |
20120121002 | Receiver and Signal Receiving Method Thereof - A signal receiving method of a receiver includes following steps. Multiple time-domain received signals are transformed into multiple frequency-domain received signals, and channel response matrices corresponding to the frequency-domain received signals are estimated. The frequency-domain received signals are STBC decoded and multiple original combination signals are obtained based on the corresponding channel response matrices. The frequency-domain received signals are rearranged, and the rearranged frequency-domain received signals are STBC decoded and multiple rearrangement combination signals are obtained based on the corresponding channel response matrices. The original combination signals and the rearrangement combination signals are randomly chosen and summed to obtain multiple complex signals. The complex signal with minimum interference power is selected and then the selected signal is used to cancel interference and compensate the channel effect to obtain the detected data. | 05-17-2012 |
20120128051 | Evaluation Device for Providing a Transceiver System with Performance Information Thereof - An evaluation device is adapted for providing a transceiver system with performance information thereof. The transceiver system includes a transmitter and at least one receiver, and models a channel between the transmitter and the receiver using Nakagami distribution with a fading parameter. The evaluation device includes a signal-to-noise ratio (SNR) setting module, an error rate computing module, and an output module. The SNR setting module is operable to set an average SNR for the channel between the transmitter and the receiver of the transceiver system. The error rate computing module is operable, based upon the fading parameter, the average SNR and a number of the receiver, to compute a bit error rate over the channel between the transmitter and the receiver. The output module is operable to provide the transceiver system with the average SNR and the bit error rate as the performance information of the transceiver system. | 05-24-2012 |
20120128052 | CARRIER FREQUENCY ACQUISITION METHOD AND APPARATUS HAVING IMPROVED RELIABILITY FOR DETECTING CARRIER ACQUISITION OR LOSS THEREOF - A carrier signal acquisition technique is disclosed. An improved course carrier frequency offset algorithm is employed in conjunction with a conventional fine carrier frequency offset algorithm. The course carrier frequency offset algorithm estimates large offsets that are multiples of the carrier spacing that may occur at system startup. A spectral null is placed in the center of the transmit spectrum and is thereafter located in a received signal. The position of the spectral null provides an estimate of the local oscillator carrier offset. A frequency finite state machine (FSM) processes a number of metrics to ensure the reliability of the course carrier frequency offset and of transitions between acquisition and tracking modes. The frequency FSM will utilize the frequency offset (modin) generated by a MODSC algorithm provided one or more predefined thresholds are satisfied. | 05-24-2012 |
20120140810 | METHOD AND APPARATUS FOR GENERATING A PRECODING MATRIX CODEBOOK GROUP - A method and an apparatus for generating a precoding matrix codebook group are provided by the present invention. The method includes: a step for generating a channel matrix set; a step for generating a performance parameter matrix; and a step for generating a precoding matrix codebook group: based on the generated performance parameter matrix, according to contribution of every precoding matrix to the performance parameter of the communication system, ranking the precoding matrices in precoding matrix universal set, so as to achieve an ordered precoding matrix universal set as the precoding matrix codebook group. A method for assigning a precoding matrix for a multi-antenna communication system, a method for transmitting data for a multi-antenna communication system, a base station and a mobile station thereof are provided by the present invention. | 06-07-2012 |
20120163440 | APPARATUS AND METHOD FOR TUNABLE WIDEBAND SOLAR RADIO NOISE MEASUREMENT - An apparatus and method for tunable wideband solar radio noise measurement is provided. Accordingly, it is possible to directly measure the absolute flux of solar radio waves in a desired frequency band using a tunable receiver, and accordingly, to protect radio communication broadcasting systems located on the earth from its damage caused due to radio burst, noise and the like. | 06-28-2012 |
20120163441 | FREQUENCY SELECTIVE MEASURING DEVICE AND FREQUENCY SELECTIVE MEASURING METHOD - A measuring device is provided that includes a first transformation device, a first time-quantization device and a selection device. The first transformation device implements a transformation of at least one signal into the frequency domain. The first time-quantization device subdivides at least one signal into several signals disposed in time succession. The selection device implements a selection of partial signals suitable for a measurement. | 06-28-2012 |
20120170635 | DYNAMICALLY ADJUSTED OFDM CHANNEL ESTIMATION FILTERING IN OFDM COMMUNICATIONS - Techniques for performing channel estimation in an orthogonal frequency domain multiplexing (OFDM) communications system include receiving a plurality of reference signals on a plurality of subcarriers, performing channel estimation to obtain a plurality of raw channel estimates based on the received plurality of reference signals, determining a number of raw channel estimates to be used for a channel estimate refinement and calculating a refined channel estimate using the number of raw channel estimates from the plurality of raw channel estimates. | 07-05-2012 |
20120170636 | METHOD AND DEVICE FOR GENERATING PRE-CODING MATRIX CODEBOOK - A method and a device for generating a precoding matrix codebook used in a multi-antenna communication system that includes determining an initial precoding matrix codebook consisted of L precoding matrixes; dividing a channel set into L channel groups being in one-to-one correspondence to the precoding matrix of the initial precoding matrix codebook; selecting a precoding matrix which optimally matches the channel group, from the precoding matrix universal set, to form a new precoding matrix codebook; judging whether the initial precoding matrix codebook and the new precoding matrix codebook are same; adopting the new precoding matrix codebook as the initial precoding matrix codebook, and if the initial and new precoding matrix codebook are not same, return to precoding; and adopting the new precoding matrix codebook as a precoding matrix codebook to be used in the multi-antenna communication system if the initial and new precoding matrix codebook are same. | 07-05-2012 |
20120177097 | METHOD FOR GENERATING HYBRID CODEBOOK AND HYBRID MU-MIMO SYSTEM - A method for generating a hybrid codebook for a Multi-User Multiple-input Multiple-Output (MU-MIMO) system includes the steps of: generating a parent matrix set including a plurality of M×M unitary matrices when the number of transmitter antennas is M; and generating a child matrix set dependent on the parent matrix set by using training vectors included in a random training set and each column for each unitary matrix of the parent matrix set as an initial vector codebook. | 07-12-2012 |
20120183035 | Methods and arrangements for detecting weak signals - The invention provides a method and an arrangement for detecting moving point-targets within a large set of noisy measurements. The method is based on Bayesian model selection where the measurements containing targets are modeled with their physical trajectories and the non-target measurements are modeled with the statistical distribution of measurements containing no targets. An a posteriori probability density function is utilized together with a optimization algorithm specifically designed for this problem. Advantages of the invention involve a numerically efficient formulation of the a posteriori probability density, combined with the optimization algorithm. The main applications of the invention are in detecting moving targets within e.g., radar, sonar, lidar and telescopic measurements. The method is also applicable for multi-instrument data fusion. | 07-19-2012 |
20120201285 | Apparatus and Method for SINR Estimation HSDPA MIMO Receiver - In an example embodiment a method comprises receiving at least one data stream from at least two transmitter antennas, wherein the at least one data stream is pre-coded by a set of weighting coefficients; receiving a pilot channel from each of the at least two transmitter antennas; processing the received at least one data stream by an equalizer with a set of equalizer filter coefficients; calculating for each of the at least one data stream following: a signal power and an interference power from other stream, if there is any intererence, at least in part based on a set of post equalizer channel coefficients and the set of weighting coefficients; a noise power at least in part based on the received pilot channels and the set of weighting coefficients; and a signal to interference and noise ratio based on the corresponding calculated signal power, interference power and noise power. | 08-09-2012 |
20120201286 | SYSTEM AND METHOD FOR IMPROVING SPECTRAL EFFICIENCY AND PROFILING OF CROSSTALK NOISE IN SYNCHRONIZED MULTI USER MULTI-CARRIER COMMUNICATIONS - A system, method, and a computer readable medium having instructions thereupon for synchronized multi-user multi-carrier communications are provided. For example, a synchronized multi-user multi-carrier communication system includes a transmitter, a receiver communicatively coupled to the transmitter via a plurality of communication channels associated with multiple users, and a computing device, coupled to at least one of the transmitter and the receiver, comprising a memory device in communication with one or more processors. The one or more processors are configured to obtain noise samples for the plurality of communication channels, determine a coupling between carriers on the plurality of communication channels, determine a noise model for a carrier based upon the noise samples and the determined coupling, and store the noise model in the memory device. | 08-09-2012 |
20120207200 | REDUCING STEADY STATE ERROR IN FIXED POINT IMPLEMENTATIONS OF RECURSIVE FILTERS - One feature includes a method for implementing a fixed point recursive filter that reduces or eliminates steady state error. The method comprises obtaining a first filter state value, processing the first filter state value to remove a scaling factor to obtain a second filter state value, ascertaining that the recursive filter has reached a steady state, determining a nonlinear drift parameter based on a difference between the first filter state value and the second filter state value multiplied by the scaling factor, and adjusting the second filter state value with the nonlinear drift parameter to reduce steady state error of the recursive filter. Ascertaining that the recursive filter has reached the steady state may include determining that a filter output value at time n is equal to a filter output value at time n−1. | 08-16-2012 |
20120219050 | METHOD AND APPARATUS FOR NOISE ESTIMATION IN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) SYSTEM - The present invention discloses a method and apparatus for performing noise estimation in an OFDM system. The method comprises: a channel estimation coefficient generation module generating a channel estimation coefficient w | 08-30-2012 |
20120230380 | METHOD FOR DETERMINING BEAMFORMING PARAMETERS IN A WIRELESS COMMUNICATION SYSTEM AND TO A WIRELESS COMMUNICATION SYSTEM - A method for determining a beamforming vector or a beamforming channel matrix in a communication system including a transmitting station and a receiving station, and a communication system are described. The transmitting and receiving stations include respective antenna groups and respective codebooks include a plurality of predefined beamforming vectors for the antenna group. | 09-13-2012 |
20120236921 | Method, Apparatus and Communication Unit - A method, an apparatus and a communication unit for generating precoding feedback information in a multiple frequency radio transmission system are disclosed. A rank for precoding matrices, wherein the rank is constant over the multiple frequencies, is selected and a plurality of precoding matrices having the selected rank are selected. A different precoding matrix is selected for each frequency subset of the multiple frequencies. | 09-20-2012 |
20120243594 | Load Estimation in Wireless Communication - A method for noise rise estimation in a wireless communication system comprises receiving ( | 09-27-2012 |
20120250751 | Variable Size Codebook for MIMO System - In a method of selecting a codebook for precoding a wireless transmission signal, a characteristic of a wireless communication channel is measured, and a codebook size is selected using (i) an expected throughput for each of a plurality of different codebook sizes given the measured characteristic of the wireless communication channel, and (ii) channel overhead associated with each of the plurality of different codebook sizes. Based on matrix selection criteria, a best matrix is selected from a codebook of the selected codebook size, and an indicator of the selected matrix is transmitted. | 10-04-2012 |
20120257664 | Method for Improving Multiuser MIMO Downlink Transmissions - A method for improving multiple-input multiple-output MIMO downlink transmissions includes obtaining a channel state information CSI report including preferred matrix index PMI for precoding, channel quality index CQI and rank index RI at a base station from user terminals through a channel feedback; applying selectively a signal-to-interference-plus-noise-ratio SINR offset to a SINR of said CSI report; applying selectively a rate matching responsive to SINR offset or the CSI report; and controlling or adjusting the SINR offset. | 10-11-2012 |
20120257665 | COMPLEX CONDITION DETERMINATION UNIT, TRANSMISSION DEVICE, COMPLEX CONDITION DETERMINATION METHOD - Disclosed is a complex condition determination unit which, to solve the problem of making it possible to change a modulation scheme adapted to rapid changes in line status, is provided with; an error-pulse switching determination means which outputs, as error-pulse determination information indicating whether an accumulated value of the number of error pulses accumulated over a predetermined period is equal to or greater than a predetermined error-pulse threshold value, the error pulses indicating whether an error exists in a received signal; a CNR (carrier-wave power to signal power ratio) modulation scheme determination means which outputs, as CNR determination information, a modulation scheme determined in accordance with a predetermined CNR threshold value and CNR information indicating the CNR of the received signal; an RSL (receive signal level) modulation scheme determination means which outputs, as RSL determination information, a modulation scheme determined in accordance with a predetermined RSL threshold value and RSL information indicating the RSL of the received signal; and a complex modulation scheme determination means which determines the modulation scheme used in order to modulate the transmission source of the received signal, in accordance with the error-pulse determination information, the CNR determination information, the RSL determination information, and received modulation scheme information indicating the modulation scheme of the received signal. | 10-11-2012 |
20120257666 | METHOD FOR DETERMINING NOTCHING PARAMETERS IN A PLC SYSTEM AND PLC SYSTEM - A method for determining notching parameters for a PLC (Power Line Communication) Signal in a PLC system, where, by notching in a targeted fashion, frequency ranges are omitted in the PLC signal and the notching parameters are selected such that any interference of the PLC signal with a radio signal is largely avoided, is characterized with regards to the determination of notching parameters even during operation of the PLC system such that, at least for a section of the PLC signals, a signal-interference ratio (SIR) is formed which, depending on the SIR, assesses the signal strength of a radio signal and, based on the assessment notching parameters, are determined or adjusted. A respective PLC system is provided. | 10-11-2012 |
20120263221 | Method And Apparatus For Determining Signal-To-Noise Ratio - In one embodiment, the method includes despreading the received signals by applying an unused channelization code, determining noise power based on output of the despreading, and determining a signal-to-noise ratio, SIR, based on the noise power and at least one of the received signals. | 10-18-2012 |
20120269250 | PEER DISCOVERY IN A WIRELESS WIDE AREA NETWORK SYSTEM - A method of wireless communication of a wireless device includes receiving a signal indicating WWAN resources that can be utilized for communicating peer discovery signals. In addition, the method includes communicating an OFDM peer discovery signal in the WWAN resources. A method of wireless communication of a base station includes transmitting a signal to a wireless device indicating WWAN resources dedicated for a silence interval that can be utilized for communicating peer discovery signals. The WWAN resources dedicated for a silence interval include a first subset of resources and a second subset of resources. The method further includes measuring noise in the first subset of resources and refraining from measuring noise in the second subset of resources. | 10-25-2012 |
20120269251 | METHOD AND APPARATUS FOR ESTIMATING SIGNAL TO NOISE RATIO IN WIRELESS COMMUNICATION SYSTEM - There is provided a method and apparatus for estimating a signal to noise ratio (SNR) in a wireless communication system. The apparatus selects a preamble signal for each of a plurality of sectors from a reception signal experienced by fast Fourier transform (FFT), outputs a correlation signal by performing a correlation between the preamble signal for each sector and a preamble reference signal, estimates power of the reception signal and noise power for each sector based on the correlation signal, selects a minimum value from among the noise powers for the sectors, outputs a net power for each sector by subtracting the minimum value from the power of the reception signal for each sector, and calculates the SNR by dividing the net power for each sector by the minimum value. | 10-25-2012 |
20120294349 | INTERFERENCE-WEIGHTED COMMUNICATION SIGNAL PROCESSING SYSTEMS AND METHODS - A level of interference affecting signal components of received communication signals is estimated and used to weight the signal components. The signal components in a each of a number of groups of signal components are weighted based on respective interference estimates to thereby adjust signal components for coloured interference, which may vary significantly between different groups of signal components. Each group of signal components may include a single component or components within a relatively narrow sub-band of the communication signals, such as a coherence bandwidth of an Orthogonal Frequency Division Multiplexing (OFDM) signal. | 11-22-2012 |
20120300827 | Method and Apparatus Reporting Channel Quality Indicator of Communication System - The present invention provides a method and apparatus reporting a channel quality indicator of a communication system, including: detecting a first measurement reflecting a first communication quality of the communication system; providing a series of thresholds and mapping functions, each mapping functions in association with a bin defined by two adjacent thresholds, so the first measurement is mapped to the channel quality indicator by the mapping function in association with the bin which matches the first measurement; and updating at least one of the thresholds according to a second measurement which reflects a second communication quality of the communication system. | 11-29-2012 |
20120314748 | NETWORK RECEIVER AND ADJUSTING METHOD THEREOF - A network receiver and the adjusting method thereof, the network receiver includes a first delay unit, a second delay unit, a first processing unit and an adjusting circuit. The first delay unit is for delaying a first signal received from a first transmission line to generate a delayed first signal. The second delay unit is for delaying a second signal received from a second transmission line to generate a delayed second signal. The first processing unit is for processing a difference between the delayed first signal and the delayed second signal to generate first data. The adjusting circuit adjusts the first and second delay units to have a plurality of delay amount combinations, the first processing unit generates a plurality of first data respectively corresponding to the delay amount combinations, and the adjusting circuit adjusts delay amount of the first and second delay units according to the first data. | 12-13-2012 |
20120320961 | CHANNEL ESTIMATION FOR OFDM SYSTEMS - A device for performing channel estimation in an OFDM system includes a non-volatile memory, a G matrix selector and a channel estimate generator. The non-volatile memory stores a set of G matrices indexed by signal to noise ratio, the G matrices being precalculated for a plurality of signal to noise ratios using a fixed Doppler frequency and a fixed delay spread. The G matrix selector uses a quantised signal to noise ratio to select a G matrix from the set of G matrices stored in the non-volatile memory. The channel estimate generator multiplies the selected G matrix by LS estimates for the reference signal to obtain a channel estimation. | 12-20-2012 |
20120320962 | Diversity Reception Device - The diversity reception device includes an antenna switching unit configured to select and switch to a determined chain number of antennas out of a plurality of antennas; and an antenna interchange control unit configured to control the antenna switching unit to interchange an antenna. The antenna interchange control unit compares a carrier-to-noise ratio measured by a demodulation circuit of a demodulation unit of each chain, controls the antenna switching unit to sequentially switch connection with an antenna of a chain having a lowest carrier-to-noise ratio to connection with antennas connectable to the chain, and interchanges the antenna of the chain having a lowest carrier-to-noise ratio with an antenna estimated to have a highest carrier-to-noise ratio on the basis of the input level measured by the level detection unit or an antenna having a highest input level measured by the level detection unit among the connection-switched antennas. | 12-20-2012 |
20120327992 | RECEIVER AND METHOD OF RECEIVING SIGNAL FOR REDUCING INTERSYMBOL INTERFERENCE - A synchronization method for a receiver includes generating, by a beacon detector, an operating signal by performing a logic operation on a baseband signal, and calculating, by a coarse sync block, a coarse FFT window start position value where a signal-to-noise ratio becomes maximized by estimating a noise level of the operating signal. | 12-27-2012 |
20130003812 | METHOD FOR SELECTING A PRECODING MATRIX IN A MULTIPLE INPUT MULTIPLE OUTPU ("MIMO") SYSTEM - A method for selecting a precoding matrix to be used in a MIMO communication system includes a transmitter, a receiver and a communication channel, wherein the precoding matrix is used by the transmitter to precode codewords to be transmitted to the receiver over the communication channel. At the receiver, an optimum precoding matrix within a codebook of precoding matrices is determined on the base of a metric related to the power of received signal layers. An indication is then fed back from the receiver to the transmitter useful to enable the transmitter to select the optimum precoding matrix from the codebook. | 01-03-2013 |
20130003813 | IMPULSE NOISE DIAGNOSIS DURING RETRANSMISSION - Disclosed and recited herein are devices, systems, methods, and programs by which data is transmitted and, when receipt of the transmitted data has not been acknowledged, an impulse noise occurrence may be diagnosed at the transmitter based on flag streams associated with data transfer units corresponding to the transmitted data. Characteristics of the impulse noise occurrence may be diagnosed based on, at least, a number of consecutive error bits in at least one of the flag streams associated with the data transfer units corresponding to the transmitted data. | 01-03-2013 |
20130003814 | Load Estimation in Frequency Domain Pre-Equalization Systems - An arrangement ( | 01-03-2013 |
20130028309 | TRANSMISSION MODE ADAPTATION IN A WIRELESS NETWORK - Conventional mode adaptation does not account for the gain imbalance between channels for measurement and for data reception. Therefore, the precoder, which is selected based on the measurement channel, may not be the optimal precoder for the data reception channel. By maintaining relative SINR ordering between transmission modes, a receiver may select the transmission mode for a transmitter that maximizes the actual throughput even in the presence of inter-antenna gain increase or decrease. | 01-31-2013 |
20130028310 | EVALUATION DEVICE FOR PROVIDING A TRANSCEIVER SYSTEM WITH TRANSCEIVING PERFORMANCE INFORMATION THEREOF - An evaluation device provides a transceiver system with performance information. The transceiver system models channels between a transmitter and a receiver thereof using Nakagami distribution with a fading parameter. The evaluation device includes a setting module, a computing module and an output module. The computing module is operable, based upon the fading parameter, an average SNR of the channels, a number of transmit antennas and a number of receive antennas, to estimate an average output SNR, a bit error rate and an outage probability related to signals received by the receiver. The output module is operable to provide the transceiver system with the average SNR and the estimated information as the performance information. | 01-31-2013 |
20130039404 | Synchronization of a Receiver to a Desired Signal - Apparatuses, methods and systems of synchronizing a receiver to a desired signal are disclosed. One method includes obtaining synchronization information of an interfering signal, and adjusting an out-of-band response of a receiver filter based at least in part on the synchronization information of the interfering signal, wherein the in-band response of the receiver filter is determined by frequency components of the desired signal. | 02-14-2013 |
20130064279 | METHODS FOR INGRESS MITIGATION IN CABLE COMMUNICATION SYSTEMS INVOLVING REPAIR, REPLACEMENT AND/OR ADJUSTMENT OF INFRASTRUCTURE ELEMENTS - Methods for reducing ingress in a neighborhood node of a cable communication system. The node includes an RF hardline coaxial cable plant and multiple subscriber service drops to convey upstream information from multiple subscriber premises over an upstream path bandwidth. A test signal having a frequency falling within the upstream path bandwidth is transmitted proximate to one or more potential points of ingress into the hardline cable plant. Based on signal amplitudes at the test signal frequency representing test signal ingress into the hardline cable plant, one or more faults in the hardline cable plant are specifically identified and remediated so as to significantly reduce a noise power in the node in at least a portion of the upstream path bandwidth below approximately 20 MHz. In one example, hardline plant-related and/or subscriber-related faults are remediated so as to significantly reduce ingress arising from terrestrial short wave radio signals. | 03-14-2013 |
20130070831 | Method And Apparatus For Low Complexity Robust Reconstruction Of Noisy Signals - Embodiments relate to a method and apparatus for low complexity robust reconstruction of noisy signals. The method includes receiving, by a receiving unit, a set of noisy measurements. The method further includes obtaining, by a reconstruction unit, an estimate of the signal based on the set of noisy measurements and a plurality of parameters. The plurality of parameters includes a projection matrix that transforms the signal from a sparse domain to a compressed domain and postulated parameters. | 03-21-2013 |
20130083835 | APPARATUS AND METHOD FOR CHANNEL QUALITY FEEDBACK WITH A K-BEST DETECTOR IN A WIRELESS NETWORK - A receiver in a multiple input, multiple output (MIMO) system is configured to perform a method for generating channel quality feedback information. The method includes receiving, from a MIMO transmitter, pilot signals in each MIMO layer. The method also includes estimating the MIMO channel using the received pilot signals and performing a QR decomposition of the estimated MIMO channel. The method further includes predicting a probability of error for each MIMO layer after the QR decomposition of the estimated MIMO channel. The method still further includes determining a corresponding signal-to-noise ratio (SNR) for each MIMO layer based on the probability of error for the each MIMO layer. | 04-04-2013 |
20130089130 | Compact Dual Receiver Architecture for Point to Point Radio - A radio frequency receiver comprising a receiver module, an intermediate frequency (“IF”) module, a synthesizer module and a controller module. The receiver module receives a radio frequency signal and provides a baseband in-phase signal and a baseband quadrature signal, eliminates a sideband of the in-phase and quadrature signals to create a first and a second signal, downconverts the first and second signal to a first and a second IF signal, and selects one of the first or second IF signals. The IF module receives the first or second IF signal, performs analog-to-digital conversion on the first or second IF signal, and demodulates the digitally converted IF signal. The synthesizer module receives a programmable reference signal, downconverts the reference signal to an IF feedback signal, downconverts the reference signal to a baseband feedback signal, provides the IF feedback signal to the IF module, and provides the baseband feedback signal to the receiver module. The controller module samples the digitally converted IF signal and provides the programmable reference signal to the synthesizer module to thereby provide a demodulated output signal. | 04-11-2013 |
20130101007 | Systems and Methods for Channel Estimation of MoCA Signals - Systems and methods are provided, for estimating a channel based on previous channel estimations from the same source. Embodiments disclosed herein enable removal of the timing variation (from burst to burst) so that the channel can be more accurately estimated. Embodiments provide several systems and methods for averaging channel estimation information from each of the bursts. The systems and methods disclosed herein advantageously improve channel estimation accuracy and reduce modulation error. | 04-25-2013 |
20130101008 | SYSTEMS AND METHODS FOR DOWNLINK SCHEDULING IN MULTIPLE INPUT MULTIPLE OUTPUT WIRELESS COMMUNICATIONS SYSTEMS - Systems and methods for downlink scheduling in wireless communications systems are described. In some embodiments, a method includes: applying channel prediction at a transmitter for transmitting information to one or more mobile devices; predicting channel state information for a channel over which the information is transmitted, the channel state information being based, at least, on the channel prediction; determining a precoding matrix to apply to the information, the determining the precoding matrix being based, at least, on predicted channel state information; and scheduling transmission of the information to the one or more mobile devices based, at least, on an asymptotic ergodic rate for the one or more mobile devices. The asymptotic ergodic rate can be based on large-scale channel behavior and a maximum Doppler shift between the mobile devices. | 04-25-2013 |
20130121392 | OFDM Receiver With Time Domain Channel Estimation - An OFDM communication system performs time domain channel estimation responsive to received symbols before the symbols are processed by a fast Fourier transform. The communication system generates virtual pilots from actual pilots to improve the stability and quality of channel estimation. The system generates a reference signal from the actual and virtual pilots and correlates the resulting reference signal with a signal responsive to the received symbol to generate an initial channel impulse response (CIR) and to determine statistics about the channel. In some circumstances, the resulting reference signal is correlated with a modified symbol in which the actual and virtual pilot locations are emphasized and the data locations are deemphasized. Time domain channel estimation iteratively improves on the initial CIR. The system determines channel estimates for data only symbols through averaging such as interpolation. | 05-16-2013 |
20130121393 | CHANNEL ESTIMATION WITH DECISION FEEDBACK - Systems, methods, and other embodiments associated with a method for estimating a channel between a wireless transmitter and a wireless receiver are described. According to one embodiment, a method includes receiving a signal that includes non-pilot data that is not known to a receiver of the signal; determining an estimated channel for the signal based, at least in part, on the non-pilot data; processing the signal based, at least in part, on the estimated channel to produce an equalized signal; and decoding the equalized signal to produce output data. | 05-16-2013 |
20130128940 | METHODS FOR DETERMINING DECODING ORDER IN A MIMO SYSTEM WITH SUCCESSIVE INTERFERENCE CANCELLATION - Certain aspects provide a method for determining decoding order and reconstruction weights for decoded streams to be cancelled in a MIMO system with successive interference cancellation, based on estimates of the channel characteristics, the received composite signal and parameters of the system. | 05-23-2013 |
20130136166 | Measuring Interference and Noise Power Using Non-Content Burst Periods - Embodiments describe a method of measuring noise and interference within transceivers of an OFDM wireless transmission system, or similar communication system, including a number of receivers communicating with one or more base stations in cell or sector arrangements. The transmitter schedules a transmission burst for a non-existent user (receiver) using wireless transmission traffic. In an OFDM system, this corresponds to a certain set of subcarriers in the time/frequency arrangement. Thus, in the receive frame structure, the data and pilot subcarriers are guaranteed to be only noise and interference from adjacent sectors. The receiver can accurately measure the noise and interference without needing to cancel out the transmitted signal. Therefore, the system is assured that there is no desired signal as part of this measurement. The noise and interference measurement process can be appropriately scheduled so that it does not impact the overall throughput of the system. This mechanism creates a deterministic place (in time and/or frequency) within the transmission, where no desired signal is required. | 05-30-2013 |
20130170533 | Coordinated Multi-Point Transmission - In a multiple-input multiple-output (MIMO) wireless system supporting Coordinated Multi-Point (CoMP) transmission and having a first base station, a second base station, and a user equipment, a communications method implemented in the first base station is disclosed. In an aspect, the communications method includes exchanging, with the second base station through local information exchange, first information about a first channel between the first base station and the user equipment and second information about a second channel between the second base station and the user equipment, and computing at least one of a precoding matrix, a receiver filter, and a projection matrix, wherein the user equipment estimates the first information and the second information, and shares the first information and the second information with the first base station. Other apparatuses and some methods for wireless communications also are disclosed. | 07-04-2013 |
20130177062 | TRANSMITTER, CONTROL METHOD, COMPUTER PROGRAM AND DELTA-SIGMA MODULATOR - In order to improve radio characteristic in a transmitter, there are included a ΔΣ modulation means that ΔΣ modulates a given input signal; and a control means that changes parameters of the ΔΣ modulation means in accordance with a given condition. | 07-11-2013 |
20130195163 | SYSTEMS AND METHODS FOR ENHANCING AUDIO QUALITY OF FM RECEIVERS - Systems and methods are described for enhancing the audio quality of an FM receiver. In embodiments described herein, quadrature L−R demodulation is applied to a composite baseband signal output by an FM demodulator to obtain an L−R noise signal. A channel quality measure is calculated based on the L−R noise signal and is used to control whether a pop suppression technique is applied to an L+R signal obtained from the composite baseband signal to detect and remove noise pulses therefrom. The channel quality measure and the L−R noise signal are also leveraged to perform single-channel noise suppression in the frequency domain on an L−R signal obtained from the composite baseband signal and on the L+R signal. The channel quality measure is also used to control the application of a fast fading compensation process that replaces noisy segments of the L−R and L+R signal with replacement waveforms generated via waveform extrapolation. | 08-01-2013 |
20130195164 | SYSTEMS AND METHODS FOR ENHANCING AUDIO QUALITY OF FM RECEIVERS - Systems and methods are described for enhancing the audio quality of an FM receiver. In embodiments described herein, a stop band noise signal is extracted from an L+R or L−R signal produced by an FM stereo decoder. A channel quality measure is calculated based on the stop band noise signal and is used to control whether a pop suppression technique is applied to the L+R signal. The channel quality measure and the stop band noise signal are also leveraged to perform single-channel noise suppression in the frequency domain on the L−R signal and on the L+R signal. The channel quality measure is also used to control the application of a fast fading compensation process that replaces noisy segments of the L−R and L+R signal with replacement waveforms generated via waveform extrapolation. | 08-01-2013 |
20130202020 | METHOD OF GENERATING INTERFERENCE SIGNALS AND DEVICE TO CARRY OUT SUCH A METHOD - A method for generating interference signals and a device to carry out said method, in which an interference signal ( | 08-08-2013 |
20130215951 | METHODS AND SYSTEMS FOR REDUCING CROSSTALK - At least one example embodiment discloses a method of determining crosstalk in a multiple-input-multiple output (MIMO) system. The method includes receiving, from at least one first remote node, upstream pilots on an upstream channel, determining upstream channel coefficients based on the received pilots, transmitting, to the at least one first remote node, downstream pilots on a downstream channel, receiving, from the at least one first remote node, loopback pilots on the upstream channel, the loopback pilots being loopback signals of the downstream pilots, and determining downstream channel coefficients based on the received downstream pilots. | 08-22-2013 |
20130223501 | Error Prediction For Two-Stage Receivers - Apparatus, methods, and programs products are disclosed that perform the following techniques: in a receiver comprising first and second stages, each stage at least decoding information corresponding to a user equipment, wherein the second stage performs decoding only if the first stage completes decoding with a fail, predicting whether decoding performed by the second stage for the user equipment will complete with a pass or fail; and prior to completion of the second stage, sending an indication of the predicted pass or fail to the user equipment. | 08-29-2013 |
20130223502 | RANK SIGNALING IN SPATIAL MULTIPLEXING - Method, receiver and computer program product for processing a signal transmitted over a wireless network from a plurality of spatially separated transmit antennas of a transmitter using a Multiple-Input Multiple-Output transmission. The signal is received at a plurality of receive antennas, the signal comprising a plurality of data streams. The channel quality for each of the data streams in the received signal is determined and based on the determined channel quality of the data streams, the number of independent data streams that can be supported in the Multiple-Input Multiple-Output transmission of the signal is determined. An indication of the determined number is transmitted to the transmitter. | 08-29-2013 |
20130223503 | REDUCING SIGNAL DEGRADATION IN WIRELESS COMMUNICATIONS BASED ON TIME REVERSAL - Techniques, apparatus and systems for providing radio frequency wireless communications based on time reversal of the channel impulse response of an RF pulse in a transmission channel between an RF transmitter and an RF receiver to enhance reception and detection of an RF pulse at the RF receiver against various effects that can adversely affect and complicate the reception and detection of the RF pulse at the RF receiver. | 08-29-2013 |
20130230086 | Delay Estimation - A delay between a first signal and a second signal is estimated. The first signal and second signals are received and for each of a plurality of candidate delays between the signals, a correlation value is determined. Based on the correlation values, one of the candidate delays is selected to be used as an estimate of the delay between the first and second signals. | 09-05-2013 |
20130230087 | METHOD AND SYSTEM FOR ANTENNA SELECTION DIVERSITY WITH BIASING - A signal quality metric is determined for each of multiple signal paths. Each of the signal paths corresponds to a respective antenna. The determined signal quality metric is modified for one or more signal paths. A subset of the signal paths is selected for receiving a signal based at least in part on the determined signal quality metrics. The selecting is biased based at least in part on the modified signal quality metrics. | 09-05-2013 |
20130243064 | EXPERT ANTENNA CONTROL SYSTEM - A method and system for actively selecting antenna sets for a client are disclosed. In a first aspect, the method comprises sending a first channel packet from a transmitter to a receiver and sending a second channel packet corresponding to the received first channel packet from the receiver to the transmitter. The method includes collecting statistics of an antenna set related to the sending of the first and the second channel packets. The method includes comparing the collected statistics to previously collected statistics of another antenna set to select one of the antenna set and the another antenna set. In a second aspect, the system comprises a processor and a memory device coupled to the processor, wherein the memory device stores an application which, when executed by the processor, causes the processor to carry out the steps of the method. | 09-19-2013 |
20130259109 | CHANNEL ESTIMATION BASED ON NOISE POWER - Disclosed are various embodiments providing processor configured to determine a received signal strength indication (RSSI) value for each of the plurality of channel taps. The processing circuitry identifies a maximum RSSI value among the RSSI values and may adjust a variable threshold range according to the maximum RSSI value. The RSSI value for each channel tap may be scaled according to a corresponding per tap noise power. | 10-03-2013 |
20130266054 | METHOD AND APPARATUS FOR ALLOCATING TRANSMISSION POWER IN MULTI INPUT MULTI OUTPUT SYSTEM - A method and apparatus for allocating transmission power in a transmission terminal having at least one antenna of a multi-input multi-output (MIMO) system are provided. The method includes: measuring inter-stream interference of a plurality of streams; measuring inter-user interference of a plurality of users; and determining the transmission power based on the inter-stream interference and the inter-user interference, wherein the transmission power is determined using an iterative water-filling algorithm in which the Karush-Kuhn-Tucker (KKT) system is iteratively applied to all of the plurality of streams and all of the plurality of users. According to the present invention, several receive antennas are mounted in the MIMO system, thereby making it possible to receive multiple streams. In addition, when the multiple streams are received, transmission power may be allocated to each transmission stream. | 10-10-2013 |
20130279555 | Method and Apparatus for Blind Detection of Secondary Pilot Signal in A Wireless Communication System - In one aspect, the present invention provides for blindly detecting the presence of one or more secondary pilot signals that are not being used to serve a communication apparatus, such as a User Equipment (UE). Among its several advantages, the approach to blind detection taught herein provides robust detection performance, yet it requires relatively few receiver resources. The contemplated apparatus, in at least one example embodiment, uses its blind detection of secondary pilot signal(s) to trigger suppression of secondary pilot interference, for improved reception performance. In a particular, non-limiting example, the apparatus operates in an HSDPA-MIMO network in a non-MIMO mode and blindly detects secondary pilot signal energy associated with the supporting network providing MIMO service to nearby equipment. | 10-24-2013 |
20130279556 | RECEIVER - A receiver comprising: one or more variable gain elements; an automatic gain control (AGC) for controlling a gain of one or more of the one or more the variable gain elements; and a frame detector configured to detect the presence of a frame in a signal received by the receiver and to output a signal to the AGC on detection of a data frame, wherein the AGC is configured to estimate a signal to noise ratio (SNR) of the received signal on receiving an input signal from the frame detector, to calculate a SNR margin between the estimated SNR and a target SNR and to adjust the gain of one or more of the one or more variable gain elements to maintain a positive SNR margin such that in the event of interference with the received signal the one or more variable gain elements do not saturate. | 10-24-2013 |
20130279557 | Interference Cancellation with Time-Varying Interference and/or Distortion - A communications receiver includes a noise analyzer to characterize the composition of the interference and/or distortion impressed onto a transmitted communications signal in the presence of one or more time-varying conditions. The noise analyzer may provide a selection signal indicating the composition of the interference and/or distortion impressed onto a transmitted communications signal in the presence of one or more time-varying conditions to be used by the communications receiver. In an exemplary embodiment, the communications receiver selects at least one set of filter coefficients to compensate for the interference and/or distortion impressed onto a transmitted communications signal in the presence of a particular time-varying interference and/or distortion condition. In another exemplary embodiment, the communications receiver selects a corresponding interference cancellation filter hank to compensate for the interference and/or distortion impressed onto a transmitted communications signal in the presence of the particular time-varying interference and/or distortion condition. | 10-24-2013 |
20130315288 | SYSTEM AND METHOD FOR TRANSMITTING DATA THROUGH A DIGITAL INTERFACE - There are disclosed systems and methods that dynamically vary the word length of data being transmitted through a digital interface. In one embodiment, the method comprises: (i) obtaining at least one parameter indicative of a quality of a signal; (ii) if the at least one parameter indicates that the quality of the signal is above a threshold, then transmitting the data as a number of digital words at a first predetermined word length; (ii) if the at least one parameter indicates that the quality of the signal is below the threshold, then transmitting the data as a number of digital words at a second predetermined word length. The second predetermined word length is different from the first predetermined word length. | 11-28-2013 |
20130322508 | Antenna Selection Technique For Fast Diversity - A fast diversity technique using either an EESM or a capacity computation can determine antenna selection in a wireless communication device. A fast Fourier transform (FFT) for the EESM/capacity computation can be performed with consecutive samples of a single symbol period of a short training field (STF) of a packet received by each antenna. The effective signal-to-noise ratio (SNR) for each antenna can be calculated using the results of the EESM or capacity computation. The antenna with the highest effective SNR is selected. | 12-05-2013 |
20130322509 | IMPLEMENTING BLIND TUNING IN HYBRID MIMO RF BEAMFORMING SYSTEMS - A system and a method for applying a blind tuning process to M antennas coupled via N beamformers to a multiple input multiple output (MIMO) receiving system having N channels, wherein M>N, are provided herein. The method includes the following steps: Periodically measuring channel fading rate at a baseband level to determine the number of antennas L out of K antennas connected to each one of the beamformers, to be combined at each one of the N beamformers; assigning the antennas to the subset L according to some criteria such as best quality indicator; repeatedly applying a tuning process to L antennas in each one of the N beamformers. | 12-05-2013 |
20130336376 | Systems for Calibration of Wireless Electronic Devices - A calibration system may be provided for calibrating wireless communications circuitry in an electronic device during manufacturing. The calibration system may include data acquisition equipment and calibration computing equipment for receiving and processing test and calibration signals from wireless communications circuitry to be calibrated. During testing and calibration operations, a device may be provided with initial pre-distortion calibration values. The initial pre-distortion calibration values may be generated at least in part based on calibration operations performed for other wireless electronic devices. The device may generate a test signal using the initial pre-distortion calibration values. The calibration system may determine whether the test signal is within an acceptable range of a known reference signal. If the test signal is outside of the acceptable range, the calibration system may generate a set of corrected pre-distortion calibration values to be used in generating wireless communications signals during normal operation of the device. | 12-19-2013 |
20130343445 | NOISE DETECTION METHOD, NOISE DETECTION APPARATUS, SIMULATION METHOD, SIMULATION APPARATUS, AND COMMUNICATION SYSTEM - For voltage values (observed noise sequence) in an electronic power line (communication medium) which are obtained at a predetermined interval, initial values of noise characteristics based on a statistic of the observed noise sequence itself are decided by a moment method (S | 12-26-2013 |
20140003481 | METHOD FOR DETERMINING BEAMFORMING PARAMETERS IN A WIRELESS COMMUNICATION SYSTEM AND TO A WIRELESS COMMUNICATION SYSTEM | 01-02-2014 |
20140036980 | METHOD AND SYSTEM FOR DETECTING NON-LINEAR DEVICES - To assist with the detection of unfiltered device(s), a system observes how the received noise changes between two links as the transmit signal is changed. Harmful unfiltered nonlinear devices will generate significant noise that depends on the transmitted signals; therefore, this additional noise can be quantified to some extent by comparing the observed noise for two different transmit signals. The total noise can be determined from the SNR if the received signal is known. The received signal may be read directly in some non-standard systems, or it may be determined from the known transmit signal and channel attenuation, which is sometimes the case in standard-compliant links, but often with a relatively large error. To circumvent this problem, certain embodiments of this invention only consider the change in noise between two links with the same channel attenuation. This differential comparison makes it unnecessary to accurately know the channel attenuation. | 02-06-2014 |
20140036981 | SYSTEMS AND METHODS FOR CHARACTERIZING TRANSMISSION LINES USING BROADBAND SIGNALS IN A MULTI-CARRIER DSL ENVIRONMENT - Using DSL modems as data collectors, the modems processes the data to, for example, allow easier interpretation of the line characteristics. In particular, the modems postprocess the data including calibration, filter compensation, determination of the SNR medley from the bits and gains tables and rate conversion. The interpretation process uses the postprocessed data and determines loop characterization, interferer detection, a data reduction estimation and a data rate estimation. The outputs of these determinations least allow for the characterization of the line conditions between the two modems. | 02-06-2014 |
20140056342 | MEASURING CHANNEL SIGNAL TO NOISE METRIC USING CONSTELLATION DATA - Described are systems and methods of estimating a Signal-to-Noise (S/N) ratio of an input channel carrying a QAM signal. A Modulation Error Ratio (MER) is calculated for the input QAM signal, but uses only the centermost error values of a constellation of the input QAM signal in generating this modified MER. The modified MER accurately represents the S/N ratio of the input channel carrying the QAM signal. In this way the S/N ratio may be accurately determined using only the received I and Q components of the modulated QAM input signal itself. | 02-27-2014 |
20140064348 | Digital Post-Distortion Compensation in Telecommunication Systems - Systems and methods are provided for compensating for analog distortion in telecommunication systems. In one aspect, a system is provided for communicating signals having frequencies in multiple frequency bands between at least one base station and at least one terminal device. The system includes a transport section, a digital filter, and a processing device. The transport section includes an analog filter. The analog filter can reduce interference from interfering signals having frequencies in frequency bands adjacent to received signals from an antenna by filtering the received signals. The processing device can modify filter coefficients of the digital filter. The digital filter with the modified filter coefficients can compensate for distortion in the received signals caused by the analog filter. | 03-06-2014 |
20140072022 | APPARATUS FOR MIMO CHANNEL PERFORMANCE PREDICTION - The invention describes a method for predicting the performance of the MLD receiver in MIMO channels. The method is based on the iterative principle where the performance of the MLD decoder is derived from that of an iterative receiver architecture with similar performance. The described Iterative MIMO Effective SNR (IMES) technique maps the performance of each MIMO channel realization into a set of effective SNR values for the different streams. This set of effective SNR values can then be used to provide link adaptation feedback to the transmitter so that the most suitable transmission format can be selected according to the characteristics of the propagation channel. Alternatively, this information can be used to adapt the receiver processing to the channel conditions, thereby making it possible, for example, to reduce the receiver power consumption in good signal conditions. | 03-13-2014 |
20140072023 | DETERMINING THE SIGNAL QUALITY OF AN ELECTRICAL INTERCONNECT - One embodiment provides a network device that includes PHY circuitry comprising transmit circuitry (Tx) and receive circuitry (Rx), wherein the Tx and Rx circuitry are configured to be coupled to a respective channel to communicate with an external device via the channels, wherein the network device configured to communicate with the external device using an Ethernet communications protocol; and test circuitry. The test circuitry is configured to: designate a through channel and at least one crosstalk channel from among the channels; determine, in the time domain, an approximate available signal voltage of a first response signal, wherein the first response signal is in response to a test signal applied to the through channel; determine a first noise profile of the first response signal in response to the test signal applied on the through channel; determine a second noise profile of a second response signal, wherein the second response signal is in response to the test signal applied on a crosstalk channel and measured on the through channel; and determine a signal-to-noise ratio of the through channel based on, at least in part, the approximate available signal voltage and the first and second noise profiles. | 03-13-2014 |
20140086295 | DETECTING FAULTS AFFECTING COMMUNICATIONS LINKS - A modem or associated computing or testing device is configured to detect the presence of one or more faults that affect DSL communications, and upon their detection, generate, for example, an indication, communication or message that recommends corrective action. In this context, a fault is generally caused by one or more unfiltered devices, impulsive noises, malfunctioning modems, or other factor that does not affect measured attenuation or measured noise, but does affect the signal-to-noise ratio (SNR) of the link. In addition to being able to generate a message guiding a user through corrective action, the system can estimate the rate impact of the detected fault. | 03-27-2014 |
20140092950 | RATE CONTROL FOR A VIRTUAL DIVERSITY RECEIVER - Devices and methods for determining transmission rates based on a virtual diversity receiver (VDR) scheme are disclosed. Performance is improved through determination of appropriate transmission rates, which are determined based on one or more signal to interference plus noise ratios (SINRs). The SINRs are calculated using virtual noise and channel coefficient values obtained as part of the VDR scheme. Utilizing an underlying pilot structure a user device may receive several sets of symbols. These symbols are then used to obtain both real and virtual channel noise power values and channel coefficients. These values and coefficients are then used to determine first and second SINR values indicative of one or more channels in the communication network. These SINR values may correlate to transmission rates (modulation order and/or coding rate). The SINRs may be sent to a base station, or the user device itself may determine one or more transmission rates. | 04-03-2014 |
20140119420 | METHODS AND SYSTEMS TO MITIGATE IMPULSE INTERFERENCE - Methods and systems to mitigate impulse interference in an OFDM QAM signal. A per-symbol noise measure, or quality measure (QM) is computed for a symbol k as a MSE of distances between carriers in the symbol and points of corresponding QAM constellations. MSE(k) is averaged over multiple symbols to compute a background signal QM, AVG_MSE(k). If MSE(k) exceeds AVG_MSE(k) by a moderate amount, symbol k may be moderately affected by impulse interference, and per-carrier SNR estimates are downgraded for all data carriers in symbol k, prior to LLR computation. SNR downgrading may be linear or step-wise based on an extent to which MSE(k) exceeds AVG_MSE(k). If MSE(k) exceeds AVG_MSE(k) by a significant amount, symbol k may be significantly affected by impulse interference, and LLRs may be set to indicate that all data carriers are erased in symbol k. | 05-01-2014 |
20140119421 | Testing Radio-Frequency Performance of Wireless Communications Circuitry Using Fast Fourier Transforms - A test system for testing wireless circuitry in an electronic device is provided. The test system may include a test host and a tester. The tester may provide radio-frequency test signals to a device under test (DUT). The DUT may include radio-frequency decoding circuitry that processes the test signals using a communications protocol and digital demodulator circuitry that processes the test signals without using the communications protocol. The digital demodulator circuitry may include transformation circuitry that performs fast Fourier transforms on the test signals to create frequency-domain performance data. The test host may compute a noise floor and signal-to-noise ratio based on the frequency-domain performance data. The test host may compare the computed noise floor and signal-to-noise ratio to predetermined thresholds to characterize the radio-frequency performance of the wireless circuitry. | 05-01-2014 |
20140126620 | APPARATUS, SYSTEM AND METHOD OF BEAM SELECTION FOR BEAMFORMED DIVERSITY WIRELESS COMMUNICATION - Some demonstrative embodiments include devices, systems and/or methods of beam selection for beamformed communication. For example, an apparatus may include a controller to control a plurality of antenna subarrays to form a plurality of directional beams for communicating a beamformed diversity wireless transmission over a plurality of selected directional links, which are selected based on at least one predefined selection metric. | 05-08-2014 |
20140133539 | METHOD AND APPARATUS FOR ANALYZING AND MITIGATING NOISE IN A DIGITAL SUBSCRIBER LINE - Data indicative of a level of stability of a DSL link is received. Based on the received data, it is determined whether the data indicates a level of stability of the DSL link that is above or below and minimum threshold. If the level of stability of the DSL link is below the minimum threshold, die noise associated with the DSL link before the time of failure is compared with the noise of failure. If the difference between the noise before and after the time of failure exceeds a threshold, then the difference in noise is characterized as a stationary noise associated with the DSL link. However, if the difference between the noise before and after the time of failure is below the threshold, a determination is made whether the failure is associated with a loss of power to the DSL link or a severe impulse noise event the difference in noise is characterized accordingly. Finally, the characterization of the noise associated with the DSL link is preserved for subsequent possible reconfiguration of the DSL link to improve link stability. | 05-15-2014 |
20140140383 | METHOD AND APPARATUS FOR RECONSTRUCTING DATA - Embodiments of the present invention provide a method and an apparatus for reconstructing data. The method includes: acquiring a self-correlation function of a root raised cosine filter coefficient and a fading factor of each antenna of channel estimation; constructing an L-dimension matrix of the self-correlation function according to the antenna; processing a result of superposing the L-dimension matrix of the self-correlation function and the fading factor of each antenna to obtain an estimate value of an actual fading factor of the each antenna; and reconstructing received data according to the estimate value of the actual fading factor to obtain reconstructed data used for cancellation. In the embodiments of the present invention, a process of performing interference cancellation for data reconstruction is closer to an actual sending process and closer to an originally sent signal, thereby improving cancellation efficiency and reducing interference. | 05-22-2014 |
20140153627 | SYSTEMS, METHODS, AND DEVICES FOR IMPROVING SIGNAL QUALITY - Improving signal quality by sampling an intermediate frequency signal by an analog-to-digital converter (ADC) and determining spectral characteristic data of the output signal of the ADC, and processing the spectral characteristic data to identify blocking signals and blocking spur signals that interfere with any desired signals. An adjustment is made to the frequency of one or more oscillators to reduce the interference resulting from the blocking signals if a ratio of the desired signal level to the total interfering blocker spur level is below a threshold. | 06-05-2014 |
20140153628 | SYSTEMS AND METHODS FOR ADVANCED ITERATIVE DECODING AND CHANNEL ESTIMATION OF CONCATENATED CODING SYSTEMS - Systems and methods for decoding block and concatenated codes are provided, including channel state information estimation such as by using optimum filter lengths based on channel selectivity and adaptive decision-directed channel estimation. These improvements enhance the performance of various communication systems and consumer electronics, including HD Radio receivers and systems. | 06-05-2014 |
20140153629 | METHOD AND APPARATUS FOR ANALYZING CROSSTALK BETWEEN LINES - Embodiments of the present invention provide a method and an apparatus for analyzing crosstalk between lines, where the method includes: performing frequency spectrum notching on a specific frequency band of lines of which the number is a first number among multiple lines, collecting a first group of state performance parameters of each line of lines of which the number is a second number among the multiple lines; canceling frequency spectrum notching on the specific frequency band of the to-be-analyzed line, collecting a second group of state performance parameters of each line of the lines of which the number is the second number; and determining, according to the first and second groups of state performance parameters, crosstalk of each line of the lines of which the number is the second number into the to-be-analyzed line on the specific frequency band. | 06-05-2014 |
20140169430 | ANTENNA RECONFIGURATION FOR MIMO COMMUNICATIONS WHEN MULTIPLICATIVE NOISE LIMITED - The MIMO method and apparatus disclosed herein improve throughput conditions limited by multiplicative noise by reducing the gain of the data streams associated with one or more dominant signal paths between MIMO communication nodes. As used herein, multiplicative noise refers to any noise dependent on or proportional to a signal strength at a transmitting node and/or a receiving node of a wireless communication network. An additional method and apparatus are included for determining that multiplicative noise limits the throughput conditions. | 06-19-2014 |
20140169431 | TECHNIQUES FOR MANAGING INTERFERENCE IN MULTIPLE CHANNEL COMMUNICATIONS SYSTEM - An apparatus may include a processor circuit, and a dynamic filter adjustment component for execution on the processor. The dynamic filter adjustment component may identify in a wideband communications signal a set of one or more interferer frequencies for one or more respective interferer channels of a set of communications channels to be filtered, select a kernel filter comprising a low pass filter having a channel width corresponding to a channel of the one or more interferer channels, and generate a co-channel interference (CCI) filter to stop the one or more interferer channels by inverting the kernel filter. Other embodiments are described and claimed. | 06-19-2014 |
20140169432 | INTERFERENCE CLASSIFICATION WITH MINIMAL OR INCOMPLETE INFORMATION - Interference classification with minimal or incomplete information. Receivers in access points and in other network devices on a wireless digital network may be switched to a spectrum monitor mode in which they provide amplitude-versus-frequency information for a chosen part of the spectrum. This may be performed by performing a FFT or similar transform on the signals from the receiver. Receivers are calibrated with known interference sources in controlled environments to determine peaks, pulse frequency, bandwidth, and other identifying parameters of the interference source in best and worst case conditions. These calibrated values are used for matching interference signatures. Calibration is also performed using partial signatures collected over a short period in the order of microseconds. These partial signals may be used to detect interferers while scanning. | 06-19-2014 |
20140177694 | METHOD AND APPARATUS FOR SENSING NOISE SIGNALS IN A WIRELINE COMMUNICATIONS ENVIRONMENT - The present invention relates to methods and apparatuses for sensing noise sources in a wireline communications environment such as a customer premises environment in a DSL system. In embodiments, the invention includes an additional sensor that is connected to power mains in a DSL customer premises environment either to characterize, at their source, noises coupling into the DSL lines, and/or to mitigate their impact into the DSL lines. One objective is associated with diagnostics that help to better characterize the noise signals themselves and derive correlation of signals sensed from the power mains and their possible projection onto the DSL line. Another objective makes use of these power line sensor signals to mitigate or to eliminate power line noises that make their way onto the DSL line. Example embodiments further include and exploit signals from additional secondary sensors such as secondary common mode, differential mode and phantom mode sensors. | 06-26-2014 |
20140269873 | ADJUSTING MULTI-CARRIER MODULATION AND TRANSMISSION POWER PROPERTIES - A tone map includes physical layer transmission properties for a multi-carrier communications channel. The physical layer transmission properties indicate modulation mode and transmission power to be used on one or more frequencies (i.e. “tones”). The transmission power may be reduced on a first frequency having a high signal-to-noise ratio (SNR) so that performance will improve for a second frequency having a lower SNR. Transmission power may be reduced on a first frequency having an unusably low SNR so that performance will improve on a second frequency. A tone map message is used to efficiently communicate modulation and transmission power adjustments on a per-carrier basis. | 09-18-2014 |
20140269874 | VARIABLE LINE CYCLE ADAPTATION FOR POWERLINE COMMUNICATIONS - Line cycle adaptation periods having variable duration are disclosed. A powerline cycle may be segmented into a plurality of line cycle adaptation periods having variable duration based upon signal-to-noise (SNR) characteristics measured at various times throughout the powerline cycle. The line cycle adaptation periods may include at least two periods with unequal durations. Each line cycle adaptation period may be associated with one or more tone maps defining physical layer transmission properties to be used by a second device for transmissions occurring during the line cycle adaptation period. | 09-18-2014 |
20140269875 | SYSTEMS, METHODS, AND DEVICES FOR ELECTRONIC SPECTRUM MANAGEMENT - Systems, methods, and devices enable spectrum management by identifying, classifying, and cataloging signals of interest based on radio frequency measurements. In an embodiment, signals and the parameters of the signals may be identified and indications of available frequencies may be presented to a user. In another embodiment, the protocols of signals may also be identified. In a further embodiment, the modulation of signals, data types carried by the signals, and estimated signal origins may be identified. | 09-18-2014 |
20140269876 | DETECTING FAULTS AFFECTING COMMUNICATIONS LINKS - A modem or associated computing or testing device is configured to detect the presence of one or more faults that affect DSL communications, and upon their detection, generate, for example, an indication, communication or message that recommends corrective action. In this context, a fault is generally caused by one or more unfiltered devices, impulsive noises, malfunctioning modems, or other factor that does not affect measured attenuation or measured noise, but does affect the signal-to-noise ratio (SNR) of the link. In addition to being able to generate a message guiding a user through corrective action, the system can estimate the rate impact of the detected fault. | 09-18-2014 |
20140286382 | Computing I/Q Impairments at System Output Based on I/Q Impairments at System Input - Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system. | 09-25-2014 |
20140301434 | TRANSMISSION APPARATUS, RECEPTION APPARATUS, COMMUNICATION SYSTEM, CIRCUIT APPARATUS, COMMUNICATION METHOD, AND PROGRAM - A communication apparatus, method, and system that reduce adverse effects caused by coupling between a transmission apparatus and a reception apparatus. The transmission apparatus includes a monitoring section that monitors an index value for a total amount of bias of a signal level in signals, a symbol identifying section that identifies a target symbol to be changed in a transmission symbol sequence comprising the signals, based on the index value for the total amount of bias of the signal level, a symbol position changing section that changes a position of the target symbol to a position of a signal point serving to reduce the bias of the signal level, and a transmission section that transmits signals included in the changed transmission symbol sequence to a reception apparatus. | 10-09-2014 |
20140314134 | METHOD AND DEVICE FOR LOCATING AN IMPAIRMENT WITHIN A TELECOMMUNICATION LINE - A method for locating an impairment within a telecommunication line may include determining measurement data related to the telecommunication line and estimating a location of the impairment depending on the measurement data. The measurement data includes crosstalk data including at least one transfer function element of a crosstalk matrix. The transfer function element characterizes a crosstalk transfer function from the telecommunication line towards the at least one further telecommunication line, and the method includes detecting oscillations in the crosstalk transfer function. | 10-23-2014 |
20140321521 | LINK PERFORMANCE ABSTRACTION METHOD AND APPARATUS IN A WIRELESS COMMUNICATION SYSTEM - A method and an apparatus for link performance abstraction for a receiver employing Interference-Aware Communications (IAC) technology in a wireless communication system are provided. A method for operating a receiving apparatus for the link performance abstraction in the wireless communication system, includes receiving an Orthogonal Frequency Division Multiplexing (OFDM) over a plurality of spatial layers, splitting and post-processing the received signal based on the spatial layers, deriving a post-processing Signal-to-Interference-plus-Noise Ratio (SINR) of each spatial layer, converting the post-processing SINR of the spatial layers to a Mutual Information per coded Bit (MIB) adaptively tuned based on an instantaneous Interference-to-Signal Ratio (ISR), and estimating a Block Error Rate (BLER) from a mean of the MIB metrics of the spatial layers. | 10-30-2014 |
20140362897 | MITIGATION OF WIRELESS SIGNAL INTERFERENCE - A signal analyzer resource monitors a signal in a downstream channel of a shared physical communication link. In response to detecting presence of wireless interference coupling onto the signal received in the downstream channel, the signal analyzer resource communicates a feedback message to a management resource (or other suitable resource) over an upstream channel of the shared physical communication link. The message indicates the presence of the wireless interference. According to a more specific configuration, the signal analyzer resource can be configured to: detect a type of modulation used to modulate data on a signal received in a channel over a shared cable network; map the detected type of modulation to a corresponding set of configuration values; and utilize the corresponding set of configuration values as a basis to monitor and/or detect a presence of wireless interference on the channel. The signal analyzer resource can mitigate affects of interference. | 12-11-2014 |
20140376604 | POWER ADAPTATION AVOIDANCE DURING CROSSTALK MEASUREMENTS - In one embodiment, the access node includes a vectoring control unit for estimating crosstalk coefficients between a set of subscriber lines based on crosstalk measurements carried out over the set of subscriber lines during a crosstalk measurement phase, and a vectoring processing unit for jointly processing, for crosstalk mitigation, signals to be transmitted over, or received from, the set of subscriber lines based on the estimated crosstalk coefficients. The access node further includes a controller configured to either postpone the execution of power adaptation over a particular line out of the set of subscriber lines after the completion of the crosstalk measurement phase, or to postpone the crosstalk measurement phase after the completion of power adaptation over the particular line. | 12-25-2014 |
20150016495 | Transmitter Noise in System Budget - One embodiment provides an apparatus. The example apparatus includes a root mean square (RMS) distortion determination module configured to determine an RMS distortion error and a signal to noise and distortion ratio (SNDR), the RMS distortion error determined based, at least in part, on a portion of a transmitted pulse centered at or near a transmitted pulse maximum amplitude and the SNDR determined based, at least in part, on the RMS distortion error. | 01-15-2015 |
20150043626 | Analysis of Captured Random Data Signals to Measure Linear and Nonlinear Distortions - A method to capture random data signals at an end point in a broadband network and process them via digital signal processing (DSP) techniques to determine both linear distortions and nonlinear distortions. In a distribution network, such as a tree and branch cable network, the location of the impairment addition can be identified by determining location of terminals have a distortion and locations of terminals that do not have a distortion. Linear distortions may be determined by an autocorrelation of the captured signal with itself. Nonlinear distortions may be determined by processing measured energy in a vacant band with manufactured energy in the vacant band. If a vacant band is not available, one can be created by demodulating a signal occupying the band, and subtracting the demodulated signal from the measured signal plus interference in a band, leaving only the interference. | 02-12-2015 |
20150043627 | NOISE DETECTION CIRCUIT, DELAY LOCKED LOOP AND DUTY CYCLE CORRECTOR INCLUDING THE SAME - A noise detection circuit includes a first delay unit suitable for delaying a periodic wave to output a delayed periodic wave, a first divider unit suitable for dividing the delayed periodic wave to output a first periodic wave, a second divider unit suitable for dividing the periodic wave to output a divided periodic wave, a second delay unit suitable for delaying the divided periodic wave to output a second periodic wave, and a detection unit suitable for comparing the first periodic wave with the second periodic wave and outputting a noise detection signal. | 02-12-2015 |
20150055692 | METHOD AND APPARATUS FOR INITIATING AND DATA COLLECTION OF SINGLE ENDED LINE TEST ON CUSTOMER PREMISES EQUIPMENT - According to certain aspects, embodiments of the invention relate to methods and apparatuses for performing diagnostics on a loop in a communications system. According to certain aspects, embodiments of the invention include performing SELT from a customer premises side of the loop. According to certain other aspects, embodiments of the invention address the issue of initiating a CPE side SELT procedure and also collecting the diagnostics data while a CPE is offline. | 02-26-2015 |
20150055693 | METHOD FOR ACQUIRING SIGNAL TO NOISE RATIO, SIGNAL RECEIVING DEVICE AND SIGNAL SENDING DEVICE - Embodiments of the present invention provide a method for acquiring a signal to noise ratio (SNR), a signal receiving device and a signal sending device. Through the embodiments of the present invention, an SNR of the signal receiving device (i.e., a receiving end) can satisfy the setting requirement, that is, the test condition that an SNR does not contain a precoding gain, so that a subsequent test is valid. | 02-26-2015 |
20150071335 | SYSTEMS AND METHODS FOR COMPENSATING ANTENNA GAIN IMBALANCE - This disclosure involves methods and systems for compensating for imbalanced transmit antenna gains. A transmit controller independently samples the received signal in each chain of a transceiver selectively adjusts the transmit power at each antenna to minimize any indicated imbalance to improve performance at the node receiving the transmission. | 03-12-2015 |
20150071336 | SYSTEM FOR DIAGNOSING AND OPTIMIZING VECTORED DSL LINES - In accordance with embodiments disclosed herein, there are provided methods, systems, mechanisms, techniques, and apparatuses for diagnosing and optimizing vectored DSL lines. For example, in one embodiment, such a system includes an interface to a first subset of a plurality of digital communication lines allocated to a vectored group and to a second subset of the plurality of digital communication lines which operate external to the vectored group; a Dynamic Spectral Management server (DSM server) to analyze the vectored group by performing the following operations for each of the plurality of digital communication lines in the vectored group: measuring a mitigated noise level for the digital communication line with crosstalk cancellation active, measuring a non-mitigated noise level for the digital communication line with crosstalk cancellation inactive, and comparing the mitigated noise level measured on the digital communication line with the non-mitigated noise level measured on the digital communication line. In such an embodiment, the DSM server of the system further issues optimization instructions based on the analysis. For example, by issuing optimization instructions for the vectored group, for lines external to the vectored group, or for both. | 03-12-2015 |
20150071337 | METHOD AND DEVICE FOR DEMODULATING DATA - Embodiments of the present invention provide a method and device for demodulating data. The method includes: determining a number of reliable bits of each path of data in M paths of data and a modulation manner used to demodulate the reliable bits of each path of data, where M is a positive integer; demodulating the reliable bits of each path of data according to the modulation manner used to demodulate the reliable bits of each path of data; and demodulating residual bits in each path of data except the reliable bits according to a maximal likelihood ML algorithm. Compared with the prior art, it is unnecessary to demodulate all bits of each path of data according to the ML algorithm, thereby lowering the complexity of demodulation by using the ML algorithm. | 03-12-2015 |
20150117505 | METHOD AND DEVICE FOR MEASURING THE CURRENT SIGNAL-TO-NOISE RATIO WHEN DECODING LDPC CODES - A method for measuring a signal-to-noise ratio when decoding Low Density Parity Check (LDPC) codes is provided. The method includes receiving from an input of a demodulator an input code word with “strong” or “weak” solutions, decoding the input code word in a LDPC decoder using a predetermined dependence of a mean number of iterations on the signal-to-noise ratio, recording a number of iterations performed during the decoding of the input code word, averaging derived values of the number of iterations for a specified time interval, estimating a signal-to-noise ratio based on averaged derived values of the number of iterations and based on the predetermined dependence of the mean number of iterations on the signal-to-noise ratio, and generating an output decoded code word. | 04-30-2015 |
20150139291 | SIGNAL GENERATOR AND SIGNAL GENERATION METHOD WITH CYCLIC PREFIX GENERATION - A signal generator for creating a measuring signal comprising a cyclic prefix comprises a baseband signal generator for generating a baseband measuring signal and a channel emulator for emulating a channel in the baseband measuring signal resulting in a channel modified signal. Moreover, it comprises a modulator for modulating the channel modified signal and a cyclic prefix generating unit for generating and inserting a cyclic prefix into the modulated signal. The cyclic prefix generating unit is set up for generating the cyclic prefix in such a manner that a channel modified cyclic prefix is emulated. | 05-21-2015 |
20150139292 | HYBRID BEAMFORMING FOR DATA TRANSMISSION - Technology to provide hybrid beamforming feedback is disclosed. In an example, a user equipment (UE) can include computer circuitry configured to: Receive a reference signal (RS) from a node; calculate an optimal channel direction from the RS; calculate an optimal signal-to-interference-plus-noise ratio (SINR) for the optimal channel direction, where the optimal SINR is conditionally calculated with an intra-cell interference component or calculated without the intra-cell interference component based on a feedback configuration; and transmit the optimal channel direction and the optimal SINR to the node. | 05-21-2015 |
20150146767 | APPARATUS, SYSTEMS AND METHODS FOR DSM ENERGY MANAGEMENT - In accordance with embodiments disclosed herein, there are provided apparatus, systems and methods for DSM energy management. For example, in one embodiment such means include: means for adjusting transmit power on a Digital Subscriber Line (DSL line) to optimize energy consumption for the DSL line; and means for changing profile settings for the DSL line responsive to adjusting the transmit power on the DSL line until performance of the DSL line at least meets a threshold performance. For example, the means for adjusting the transmit power may involve reducing the transmit power on the DSL line to reduce total transmission energy consumption of the DSL line in accordance with one embodiment. In other embodiments, transmit power is adjusted upwards, a transmit spectra is adjusted, or effectiveness of such adjustments are measured. | 05-28-2015 |
20150295664 | CALIBRATION DEVICE AND CALIBRATION METHOD - A calibration device includes a continuous wave signal generator that generates a continuous wave signal having a predetermined amplitude, a quadrature modulator that amplifies the continuous wave signal using a variable gain and performs quadrature modulation of the amplified continuous wave signal to generate a radio frequency signal, an envelope detector that detects an envelope of the radio frequency signal, a gain adjuster that adjusts the variable gain, based on power of the detected envelope, a correction value searcher that searches for a correction value that provides a minimum value of a fluctuation amount of an amplitude of the envelope, and a corrector that adds the correction value obtained through the search by the correction value searcher to the continuous wave signal and outputs the continuous wave signal after the addition to the quadrature modulator. | 10-15-2015 |
20150304133 | SYSTEM AND METHOD FOR IQ IMBALANCE ESTIMATION - Systems and methods for estimating IQ imbalance in a communication system are provided, where a first device is configured to perform a self-characterization. The self-characterization is performed by requesting an IQ probe from a second device. The first device receives tones via the IQ probe with frequency separation such that an image related to one IQ imbalance is separated from an image related to another IQ imbalance. IQ imbalance can be estimated by calculating tone to image ratio. | 10-22-2015 |
20150341090 | APPARATUS AND METHOD FOR PROCESSING TRANSMISSION/RECEPTION SIGNALS FOR INTERFERENCE ALIGNMENT IN MU-MIMO INTERFERING BROADCAST CHANNEL - A method comprising: determining, by a transmitter, a fixed number of effective IAI channels; estimating, by a receiver, channel information H through information provided from the transmitter; sharing, by a receiver, the channel information among a plurality of receivers that are belonging to a same BSS (Basic Service Set); calculating effective IAI channel information q and decoding vector u using the channel information; feeding back the calculated effective IAI channel information q and decoding vector u to the transmitter; and calculating, by the transmitter, a transmitting precoding vector, after sharing the fed-back effective IAI channel information q and decoding vector u, and the channel information H among a plurality of other transmitters. | 11-26-2015 |
20150349899 | SYSTEM AND METHOD FOR AUTOMATED LOSS TESTING - A method and device for analyzing time domain waveforms traveling in electronic interconnect for the purpose of measuring the attenuation. This includes the use of an automated processing system and method to transmit a TDR step pulse into one end of an interconnect and to record the time domain waveform response from the same end of the interconnect. The processing algorithms separate the portions of the collected time domain waveform which contain return loss and insertion loss information and process each portion of that waveform data through FFT techniques to extract the frequency dependent loss data. The method describes the calibration techniques required to achieve these measurements and the device utilized can be a manual or robotic probing system. | 12-03-2015 |
20150349918 | DOWN-HOLE INTELLIGENT COMMUNICATION SYSTEM BASED ON THE REAL-TIME CHARACTERISATION OF THE ATTENUATION OF SIGNALS IN A COAXIAL CABLE USED AS A TRANSMISSION MEDIUM - The invention comprises real-time down-hole intelligent communication based on the characterisation of signal attenuation caused by a coaxial cable used as a communication medium and by frequency response changes of the electronic components of the transmitters and receivers, generated by the down-hole operating environment. The invention relates to a method for the real-time characterisation of the attenuation response of a two-way communication system using a coaxial cable, consisting in: generating test tones for the real-time characterisation of the attenuation response of a two-way communication system in the transmission and reception bands, measuring the signals received, estimating noise and the ratio to the communication signal, comparing with reference responses, adjusting the transmission and reception frequencies in order to maintain the communication with the maximum signal-to-noise ratio. The invention also relates to an adaptive two-way transmitter/receiver system for communication using coaxial cable as a link means, formed by: a transmitter with automatic adjustment of the operating band by means of the real-time characterisation of the attenuation response of a two-way communication system. The invention further relates to adjustable filtering and coupling devices for optimising the transmission and reception hands, and a control module capable of measuring the transmission and reception attenuation responses | 12-03-2015 |
20150350000 | CALIBRATION METHOD AND CALIBRATION APPARATUS FOR CALIBRATING MISMATCH BETWEEN FIRST SIGNAL PATH AND SECOND SIGNAL PATH OF TRANSMITTER/RECEIVER - A method for calibrating mismatches of an in-phase signal path and a quadrature signal path of a receiver is proposed in the present invention, including: utilizing the receiver to receive at least one test signal with a specific frequency via the first signal path and the second signal path, to generate a first signal path received signal and a second signal path received signal; performing frequency analysis upon the first signal path received signal and the second signal path received signal respectively, to generate a first frequency analysis result and a second frequency analysis result; and calculating at least one calibration coefficient according to the first frequency analysis result and the second frequency analysis result. A method for calibrating mismatches of an in-phase signal path and a quadrature signal path of a transmitter is also proposed in the present invention. | 12-03-2015 |
20150381468 | Downstream OFDM Signal Egress Detection - A cyclic prefix which duplicates some samples of a terminal portion of a symbol in an OFDM data stream and which is invariant in pilot tones can be detected in the presence of signals having higher levels of noise and broadcast signals by autocorrelation with one of two selected “lags”. Autocorrelation will be found when the lag is equal to the number of samples in the FFT used to form a symbol in the data stream. A far stronger autocorrelation is found when the lag is equal to the sum of the FFT length and the length of the cyclic prefix and applied to pilots in the data stream. Overbuilt systems can be distinguished from a system of interest by use of pilots that do not coincide in frequency with a pilot of an overbuilt system. | 12-31-2015 |
20160020792 | SIGNAL DETECTION AND CHARACTERIZATION - A method and system for detecting and characterizing an input signal receive a signal having an in-phase (I) component and a quadrature-phase (Q) component. A first IQ sample of the signal is acquired at a first point in time, and a second IQ sample of the signal is acquired at a second point in time, Using one or more processors, a delayed complex conjugate multiply (DCM) is applied to the first IQ sample of the signal and the second IQ sample of the signal to produce a constant product having an in-phase (I | 01-21-2016 |
20160020925 | SYSTEM AND METHOD FOR IQ IMBALANCE ESTIMATION - A system for IQ balance estimation is disclosed and may include requesting an in-phase and quadrature (IQ) probe comprising tones, receiving the tones with a frequency separation between images of the tones, the frequency separation being a result of a frequency shift at a requestor of the IQ probe, and calculating an estimate of IQ imbalance for each received tone. The system may also include requesting an IQ probe, receiving the tones with a frequency separation, and calculating an estimate of IQ imbalance for each received tone by determining an image to tone ratio based on the received tones. The requesting of the IQ probe, the receiving of the tones, and the calculating of the image to tone ratio may be repeated the results of the calculations of the image to tone ratio may be averaged. Gain, phase, and delay parameters may be calculated to compensate for the IQ imbalance. | 01-21-2016 |
20160028423 | NOISE POWER ESTIMATION IN DIGITAL COMMUNICATIONS SYSTEMS WITH FAST FADING CHANNELS - An accurate and fast method for estimation of noise power in digital communication systems is presented. Exemplary embodiments of the present invention do not rely upon the need for embedding reference sequences in the transmitted data. Accordingly, such exemplary embodiments are especially suited for tracking variations of noise power in digital communication systems with fast fading channels. | 01-28-2016 |
20160036508 | APPARATUS AND METHODS FOR ADAPTIVE ANTENNA DIVERSITY IN A MULTI-ANTENNA SYSTEM - Apparatuses and methods are disclosed for determining a dominant figure-of-merit for an antenna system comprising a primary antenna, and at least two diversity antennas. The dominant figure-of-merit is determined from at least two figure-of-merit types related to performance of the primary antenna when paired with one or the other of the at least two diversity antennas. The disclosed apparatuses and methods include switching to one or the other of the at least two diversity antennas, to obtain the dominant figure-of-merit, in response to a signal quality metric's relationship to the at least two figure-of-merit types. | 02-04-2016 |
20160043772 | METHOD AND APPARATUS FOR SENSING NOISE SIGNALS IN A WIRELINE COMMUNICATIONS ENVIRONMENT - The present invention relates to methods and apparatuses for sensing noise sources in a wireline communications environment such as a customer premises environment in a DSL system. In embodiments, the invention includes an additional sensor that is connected to power mains in a DSL customer premises environment either to characterize, at their source, noises coupling into the DSL lines, and/or to mitigate their impact into the DSL lines. One objective is associated with diagnostics that help to better characterize the noise signals themselves and derive correlation of signals sensed from the power mains and their possible projection onto the DSL line. Another objective makes use of these power line sensor signals to mitigate or to eliminate power line noises that make their way onto the DSL line. Example embodiments further include and exploit signals from additional secondary sensors such as secondary common mode, differential mode and phantom mode sensors. | 02-11-2016 |
20160149675 | Transmitter Noise in System Budget - One embodiment provides an apparatus. The example apparatus includes a root mean square (RMS) distortion determination module configured to determine an RMS distortion error and a signal to noise and distortion ratio (SNDR), the RMS distortion error determined based, at least in part, on a portion of a transmitted pulse centered at or near a transmitted pulse maximum amplitude and the SNDR determined based, at least in part, on the RMS distortion error. | 05-26-2016 |
20160156424 | INTERFERENCE MITIGATION FOR POSITIONING REFERENCE SIGNALS | 06-02-2016 |
20160173212 | PACKET DETECTION METHOD BASED ON NOISE POWER ESTIMATION USING ORTHOGONAL SEQUENCE, TRANSMITTER, AND RECEIVER | 06-16-2016 |
20160182097 | Systems and Methods for Transmitter Receive Band Noise Calibration for Envelope Tracking and Other Wireless Systems | 06-23-2016 |
20160182124 | DETERMINING THE SIGNAL QUALITY OF AN ELECTRICAL INTERCONNECT | 06-23-2016 |
20160204830 | MINIMIZING INTERFERENCE BETWEEN COMMUNICATION NETWORKS | 07-14-2016 |
20180026737 | DETERMINING AMBIENT NOISE IN A DEVICE UNDER TEST ELECTROMAGNETIC COMPATIBILITY TEST ENVIRONMENT | 01-25-2018 |
20180027427 | EXCURSION COMPENSATION IN MULTIPATH COMMUNICATION SYSTEMS WITH A CYCLIC PREFIX | 01-25-2018 |
20190149373 | SYSTEMS AND METHODS FOR NONLINEAR DISTORTION DISCOVERY IN ACTIVE CARRIERS | 05-16-2019 |