| Entries |
| Document | Title | Date |
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| 20080205563 | Digital Filter - The invention provides a particular construction for digital filters in which, instead of multiplying various ones of the digital samples by weights and adding the results together, one or more of the digital samples is inspected by a ranging unit, which then instructs an incrementing unit to increment, decrement or leave alone one of the samples to provide the result. In order to achieve very high data rates, the incremented and decremented values can be pre-prepared whilst the ranging unit makes its decision, and then a multiplexer responsive to the output of the ranging unit is used to select the appropriate one of the pre-prepared values. | 08-28-2008 |
| 20080212727 | Method for Receiving a Multicarrier Signal Using at Least Two Estimates of a Propagation Channel and Corresponding Reception Device - A method is provided for receiving a multicarrier signal including a time-based succession of symbols, each including a plurality of multicarriers bearing data, at least one of said symbols including at least one reference pilot. The method includes the following steps: a first estimation of a propagation channel, in accordance with a first estimating technique taking into account the or said reference pilots; at least one second estimation of said propagation channel, in accordance with a second estimating technique different from said first technique; comparing said first and second estimations, delivering an error signal; detecting at least one interfering signal in said propagation channel, by analyzing said error signal. | 09-04-2008 |
| 20080226001 | ADJACENT CHANNEL INTERFERENCE DETECTION FOR WIRELESS COMMUNICATION - Techniques for detecting adjacent channel interference (ACI) in a wireless communication system are described. Input inphase (I) and quadrature (Q) samples are filtered with a first filter response to obtain filtered I and Q samples. The first filter response is designed to pass signal in an adjacent frequency channel while suppressing signals in a desired frequency channel and non-adjacent frequency channels. Correlations of the filtered I and Q samples are determined. The presence of ACI is detected based on the correlations of the filtered I and Q samples and the power of the input I and Q samples. If ACI is present, then whether the ACI is from a higher frequency channel or a lower frequency channel is determined based on one or more of the correlations. The input I and Q samples are filtered with a second filter response that is adjusted based on the detection of ACI. | 09-18-2008 |
| 20080226002 | System and method for broadband pulse detection among multiple interferers using a dynamic filter receiver - A system and method to detect broadband pulses in the presence of multiple strong narrow band interferers is disclosed whereby a dynamic filtering method is used to detect and notch out the interfering signal by forming notch filters at the precise location of the narrow band interferers. | 09-18-2008 |
| 20080240315 | Method of processing a digital signal derived from an analog input signal of a GNSS receiver, a GNSS receiver base band circuit for carrying out the method and a GNSS receiver - For suppression of continuous wave interferers at, e.g., up to four interferer frequencies (f | 10-02-2008 |
| 20080240316 | Receiver, Receiving Method, Filter Circuit, and Control Method - A receiver supporting a plurality of radio communication systems having different specifications includes a setting unit, a clock generation circuit, a voltage-current conversion amplifier, a switch, integrators, an AD conversion circuit, and a feedback circuit. The setting unit sets a value suitable for a carrier frequency used in one selected radio communication system. The clock generation circuit generates a first clock having a first frequency and a second clock having a second frequency. The conversion amplifier converts an input voltage signal into a current signal. The switch switches between connection and disconnection modes in accordance with the first clock to output the current signal. Each integrator operates in accordance with the second clock and includes two or more switched capacitor circuits and an operational amplifier. The AD conversion circuit converts a signal supplied from the preceding integrator into digital form. The feedback circuit operates in accordance with the second clock. | 10-02-2008 |
| 20080240317 | DIGITAL FILTER - Digital filter ( | 10-02-2008 |
| 20080247495 | MULTI-SYSTEM SIGNAL RECEIVING DEVICE AND METHOD THEREOF - A receiving device includes: a first signal processor, for receiving a radio frequency signal, and converting the radio frequency signal to generate a first signal, where the radio frequency signal includes a plurality of frames; a second signal processor, coupled to the first signal processor, for performing a Fourier transform operation on the first signal according to a synchronization signal to generate an output signal; a first filter, coupled to the first signal processor, for filtering the first signal to generate a second signal; and a synchronization detection circuit, coupled to the first filter, for detecting the second signal to generate the synchronization signal. The first signal includes a channel signal and at least a portion of neighboring channel signals from neighboring channels, and the output signal corresponds to the channel signal. | 10-09-2008 |
| 20080273639 | Adaptive methods employing optimal convergence factors for processing complex signals and systems - Complex adaptive methods for complex information processing employ optimal individual convergence factors for real and imaginary components of the weight vector. For wireless receivers operating on QPSK, a Complex IA-ICA performs better than existing Complex Fast-ICA methods in terms of accuracy and convergence speed, can process such complex signals in time-varying channels, and employs time-varying and time-invariant convergence factors, independent for the real and imaginary components of the system parameters, and provide individual or group system parameter adjustments. Such systems employ the within complex adaptive ICA with individual element adaptation (Complex IA-ICA). In adaptive beamforming, system identification and other adaptive systems based on the Least Squares method, complex least mean square methods, with optimally and automatically derived convergence factors, are employed and which perform much better in terms of convergence speed and accuracy, when compared to the traditional Complex LMS and Block Complex LMS methods. | 11-06-2008 |
| 20080279318 | Combined multirate-based and fir-based filtering technique for room acoustic equalization - A combined multirate-based Finite Impulse Response (FIR) filter equalization technique combines a low-order FIR equalization filter operating at a lower rate for equalization of a loudspeaker-room response at low frequencies, and a complementary low-order minimum-phase FIR equalization filter operating at a higher rate for equalization of the loudspeaker-room response at higher frequencies. The design of two complementary band filters for separately performing low and high frequency equalization, keeps the system delay at a minimum while maintaining excellent equalization performance. Splicing between the two equalization filters, for maintaining a flat magnitude response in the transition region of the two complementary filters, is done automatically through level adjustment of one equalization filter relative to the other. The present invention achieves excellent equalization at low filter orders and hence reduced computational complexity. | 11-13-2008 |
| 20080310566 | FREQUENCY SYNCHRONIZING CIRCUIT, METHOD, AND RECEIVING APPARATUS USING THE CIRCUIT AND THE METHOD - A frequency synchronizing circuit includes a first raising unit configured to raise a received signal by a first power to obtain a first raised signal, a filter to suppress noise in the first raised signal to obtain a filtered signal, a second raising unit configured to raise the filtered signal by a second power to obtain a second raised signal, an estimating unit configured to estimate a frequency offset in the received signal based on the second raised signal to obtain an estimated value, and an offset-cancelling unit configured to cancel the estimated value from the received signal, to output an offset cancelled signal. | 12-18-2008 |
| 20080317180 | RECEIVING APPARATUS CAPABLE OF REMOVING INTERFERENCE SIGNAL AND METHOD THEREOF - An apparatus and method capable of interference signal removal is provided. The receiving apparatus includes a signal reception unit, a sampler which samples signal with carrier wave frequency, a signal filter, and a signal combiner. | 12-25-2008 |
| 20090052597 | SCALABLE RECONFIGURABLE CONCURRENT FILTER FOR WIDE-BANDWIDTH COMMUNICATION - The invention relates to a reconfigurable continuous FIR filter. The reconfigurable continuous FIR filter includes a delay line including at least two delay elements coupled in cascade. The reconfigurable continuous FIR filter also includes a filter section including at least three gain-phase elements. The filter section also includes a summing circuit having a plurality of inputs at least equal in number to the at least three gain-phase elements and one output. The reconfigurable continuous FIR filter is configured to exhibit a filter transfer function that is reconfigurable in real time. The invention also related to down-converters using the reconfigurable continuous FIR filter. The invention also related to electromagnetic wave receivers using the reconfigurable continuous FIR filter. The invention also relates to a method for reconfigurable real time continuous filtering. | 02-26-2009 |
| 20090074120 | AUTO-CALIBRATION FOR A FILTER - A filter is configured to receive a filter charging signal and to produce a filter output signal based on the filter charging signal. The filter includes an element array with one or more switched elements which include an element and a switch configured to connect the element to or disconnect the element from the array, thereby altering a time constant of the filter. A comparator is configured to receive the filter output signal and a reference signal corresponding to a value of the filter output when the time constant has a defined value, and to generate a comparator output signal based on a comparison of the filter output signal to the reference signal. A controller is configured to receive the comparator output signal and, based on the comparator output signal, output an array control signal configured to adjust one or more switches of the one or more switched elements of the element array to alter the time constant such that a value of the time constant approaches the defined value. | 03-19-2009 |
| 20090080581 | TIME SEQUENTIAL PROCESSING OPERATIONS - At least some of the arithmetic operations of a filter or other digital process can be performed time sequentially, which may allow the arithmetic elements for the filter or other digital process to be used multiple times for multiple operations. | 03-26-2009 |
| 20090086865 | Differential Signal Comparator - A differential signal comparator includes an input circuit operative to provide an absolute input current difference value that is associated with the absolute difference of differential input signal levels, and a reference circuit operative to provide an absolute reference current difference value that is associated with the absolute difference of the reference signal levels. Current comparison of the absolute input current difference value with the absolute reference current difference value identify whether an input differential signal is bigger than the reference noise level and should be processed, or an input differential signal is smaller than the reference noise level and should not be processed. | 04-02-2009 |
| 20090086866 | DEVICE, SYSTEM, AND METHOD OF FLICKER NOISE MITIGATION - Device, system, and method of flicker noise mitigation. For example, an apparatus includes a digital adaptive filter to mitigate flicker noise from a received Orthogonal Frequency-Division Multiplexing (OFDM) signal, wherein the digital adaptive filter includes: a prediction filter to estimate a value of the flicker noise based on linear combination of past low-pass filtered signal samples; a trainer sub-circuit to modify a coefficient of the prediction filter based on a difference between: a known incoming signal filtered by the prediction filter in a training stage, and a locally-generated reference copy of the known signal; a first path including a first pair of analysis-synthesis filters; and a second, parallel, path including a second pair of analysis-synthesis filters and further including the prediction filter. | 04-02-2009 |
| 20090097601 | MULTI-DYNAMIC MULTI-ENVELOPE RECEIVER - The present invention is a system and a method of filtering a signal at a receiver, the signal having at least a desired channel and blockers. A first converter converts a first copy of the signal resulting in a relatively narrow band, high-resolution first signal. A second converter converts a second copy of the signal resulting in a relatively wide band, low-resolution second signal. Once each copy of the signal is converted, the copies are passed to a combiner. At the combiner, the two copies of the signal are analyzed and the desired channel is extracted from the first copy of the signal by removing any inter-modulation product caused by any interference detected in the second copy from the blockers (not detected in the first copy). | 04-16-2009 |
| 20090116595 | SYSTEM AND METHODS FOR DETERMINING MASKING SIGNALS FOR APPLYING EMPIRICAL MODE DECOMPOSITION (EMD) AND FOR DEMODULATING INTRINSIC MODE FUNCTIONS OBTAINED FROM APPLICATION OF EMD - A computer-implemented method of signal processing is provided. The method includes generating one or more masking signals based upon a computed Fourier transform of a received signal. The method further includes determining one or more intrinsic mode functions (IMFs) of the received signal by performing a masking-signal-based empirical mode decomposition (EMD) using the at least one masking signal. | 05-07-2009 |
| 20090122930 | Apparatus With a Plurality of Filters - An apparatus comprises a filter unit comprising a plurality of different filters each configured to filter a first signal when selected. The apparatus may further comprise a control unit configured to select one of the plurality of filters depending on a strength of the first signal. Related methods may also be performed. | 05-14-2009 |
| 20090122931 | Adaptive Digital Filter, Signal Processing Method, FM Receiver, and Program - An adaptive digital filter is provided with a filter unit for generating and supplying an output signal by means of a convolution operation of an input signal and a filter coefficient, or a filter unit for taking as input signal a complex signal in which one of two signals that are generated from one real signal and that have phases that differ by 90° is a real part and the other signal is an imaginary part for generating and supplying an output signal that is a complex signal by means of a convolution operation of the input signal and a filter coefficient that is the real signal; and the update amount of the filter coefficient is controlled based on the estimated value of the amplitude of at least one of the input signal and output signal of the adaptive digital filter. | 05-14-2009 |
| 20090122932 | Adaptive digital filter, signal processing method, fm receiver, and program - A complex signal in which one of two signals that are generated from one real signal and that have phases shifted from each other by 90° is a real part and the other signal is an imaginary part is applied as input to an input terminal. A filter unit generates an output signal that is a complex signal by means of a convolution operation of this input signal and filter coefficients that are real signals and supplies the result to an output terminal. A coefficient control unit composed of a common unit and separate units controls the envelope target value based on the input signal and updates the filter coefficients such that the value of the envelope derived from the output signal approaches the envelope target value. | 05-14-2009 |
| 20090122933 | Information Handling System Including Adaptive Interference Suppression Feature And Method Of Operation - An information handling system includes a wireless device and interference suppression apparatus that adapts to the different interference problems experienced by the wireless device when the system changes from one operating mode or state to another. The interference suppression apparatus includes a controller that instructs an adaptive filter with respect to the appropriate filter characteristics to employ to suppress interference when the system is operating in a first mode. When the system changes to a second mode of operation, the interference suppression apparatus updates the filter characteristics to filter characteristics which are appropriate for suppressing interference associated with the second mode of operation. | 05-14-2009 |
| 20090129523 | DIGITAL SIGNAL RECEIVING APPARATUS - A digital signal receiving apparatus includes a detection-judging portion having a first smoothing filter generating a first smoothed signal by smoothing an auto-correlation signal and judging a possible presence of a desired signal when a signal level of the first smoothed signal is greater than a reference level and an absence of the desired signal when being smaller than the reference level. The smoothing filter includes a limiting portion limiting a fluctuation width of the first smoothed signal; and an adjusting portion configured to adjust the fluctuation width of the first smoothed signal limited by the limiting portion to be reduced while an elapsing time after the detection-judging means judges the possible presence of the desired signal is increasing. | 05-21-2009 |
| 20090135973 | Filter and Method for Suppressing Effects of Adjacent-Channel Interference - A filter device and method for suppressing effects of Adjacent-Channel Interference of a received signal in a Frequency-Division-Multiple-Access system by filtering a baseband signal of the received signal. The filter device comprises an interference filter, which is a complex digital Single-Input-Multiple-Output, SIMO, filter that is adapted to simultaneously generate a first signal filtered at an upper-frequency-band and a second signal filtered at a lower-frequency-band, wherein the first signal is separate from the second signal. The filter device also comprises a selector adapted to select one of the signals as the output from the filter device. | 05-28-2009 |
| 20090154622 | System and Method for Filter Response Switching - A system and method are provided for efficiently switching a loop bandwidth using stored values in a digital filter of a phase-locked loop system. In a first timeslice, an input signal is digitally filtered using base coefficients multiplied by stored filter output and input values from previous timeslices. The filter output value is used to acquire the input signal frequency in a first bandwidth. In response to changes in the input signal frequency, the input signal is digitally filtered in a predetermined number of first intermediate period timeslices using transient coefficients multiplied by stored filter output and input values from previous timeslices. As a result, the first filter output value is maintained within a predetermined range. In a second timeslice, the input signal is digitally filtered using base coefficients multiplied by stored filter output and input values from previous timeslices to acquire the input signal frequency in a second bandwidth. | 06-18-2009 |
| 20090168932 | MULTIPLE STREAM MULTIPLE RATE RESAMPLING COMPONENT - A method of resampling a digital signal involves serially receiving a plurality of samples of said digital signal and applying a plurality of filter coefficients to a first subset of the plurality of samples to generate a first plurality of intermediate results and to a second subset of the samples to generate a second plurality of intermediate results. The first plurality of intermediate results is accumulated to generate a first resampled value, and the second plurality of intermediate results is accumulated to generate a second resampled value. Upon receipt, each signal sample may be used to update each of a plurality of running accumulation values and then discarded before receipt of a next signal sample. Furthermore, multiple signals may be resampled concurrently using a single filter path by multiplexing circuit components, such as memory blocks. | 07-02-2009 |
| 20090190700 | METHODS AND DEVICES FOR PROCESSING SIGNALS TRANSMITTED VIA COMMUNICATION SYSTEM - A method for processing signals transmitted via a communication system includes: generating a first parameter associated with a signal power of a first signal; performing an adjacent channel interference (ACI) filtering operation upon the first signal to generate a second signal; generating a second parameter associated with a signal power of the second signal; comparing the first parameter with the second parameter to generate a comparison result; and detecting whether ACI exists in the communication system according to the comparison result to generate a detection result. | 07-30-2009 |
| 20090196385 | SYSTEMS AND METHODS FOR DETECTING A SIGNAL ACROSS MULTIPLE NYQUIST BANDS - Systems and methods for detecting a signal across multiple Nyquist bands. The systems include an analog to digital converter (ADC), a clock signal generator configured to output a sample clock signal to the ADC, and a processor configured to process sampled signals and control the clock signal generator. The processor is configured to iteratively identify a desired signal, determine whether a possible interfering signal exists at a next sampling rate, and instruct the clock signal generator to generate the next sampling rate if the processor determines that a possible interfering signal does not exist. The methods include sampling an input signal at a first sampling rate, processing the sampled signal to extract information from a desired signal, determining whether a possible interfering signal exists at a next sampling rate, and sampling at the next sampling rate if it is determined that a possible interfering signal does not exist. | 08-06-2009 |
| 20090196386 | System and Method for Blind Identification of Multichannel Finite Impulse Response Filters Using an Iterative Structured Total Least-Squares Technique - A system for, and method of, blind identification of multichannel finite impulse response filters. In one embodiment, the system includes: (1) a decomposition generator configured to construct, from noisy symbols containing data, a block-Hankel structured matrix and a decomposition thereof, (2) an iterative matrix re-estimator coupled to the decomposition generator and configured iteratively to re-estimate singular vectors corresponding to a scalar that satisfies the block-Hankel matrix until a sufficient convergence occurs, (3) a structured low-rank estimate matrix generator coupled to the iterative matrix re-estimator and configured to generate a block-Hankel structured low-rank estimate matrix related to the block-Hankel structured matrix and (4) an STLS channel estimator coupled to the structured low-rank estimate matrix generator and configured to obtain STLS channel estimates from the block-Hankel structured low-rank estimate matrix. | 08-06-2009 |
| 20090232261 | Method for Detecting a Signal, Detector and Computer Program Product - A method for detecting a signal received via a communication channel, the communication channel being affected by noise, is described, wherein the received signal is processed according to a filtering step ( | 09-17-2009 |
| 20090245444 | FAR-END CROSSTALK CANCELING METHOD AND DEVICE, AND SIGNAL PROCESSING SYSTEM - A method for remote crosstalk cancellation, includes: the combination transmitting signal is performed a pre-coding of crosstalk cancellation in the manner of self-adapting filtering, the self-adapting changes of the values of filtering parameters are guided correctly with the influence of the crosstalk component in the received signals which is reflected indirectly by relevant values of the noise statistic reported by the receiver. A corresponding device and a signal processing system for remote crosstalk cancellation are provided. The self-adapting adjustment of the values of filtering parameters has a favorable astringency and an effect for crosstalk cancellation, avoiding the need to know the channel transmission matrix in advance, while absolutely avoiding the conflict to the existing transmission standard. | 10-01-2009 |
| 20090257536 | SIGNAL EXTRACTION - The invention relates to an adaptive method of extracting at least of desired electro magnetic wave signals, sound wave signals ( | 10-15-2009 |
| 20090290667 | JOINT SYMBOL, AMPLITUDE, AND RATE ESTIMATOR - The system in one embodiment relates to tightly integrating parameter estimation, symbol hypothesis testing, decoding, and rate identification. The present invention provides Turbo-decoding for joint signal demodulation based on an iterative decoding solution that exploits error correction codes. The system iteratively couples an initial amplitude estimator, a symbol estimator, a bank of decoders, and a joint amplitude estimator to produce the symbol estimates. | 11-26-2009 |
| 20090304133 | JAMMER CANCELLER FOR POWER-LINE COMMUNICATION - An embodiment is a method and apparatus to cancel signal interference. A jammer remover removes an interfering signal from an input signal to generate a jammer-canceled signal using an adaptive filtering procedure. A jammer detector detects interference caused by the interfering signal. | 12-10-2009 |
| 20090310725 | Space Domain Filter Detecting Method In A Multi-Antenna Wireless Communication System - A space domain filter detecting method in a multi-antennas wireless communication system, processing differently with the interference from the time domain and the space domain, which proceeds the interference elimination in matched filter manner for the interference signals from all antennas in the other time, and proceeds the filtering in corresponding manner for the interference signals from the other antennas in present time, comprises the following steps: firstly, the received signals are matched-combined in time domain and space domain; secondly, with the combined signals as the observation value for detecting, the filtering is proceeded in space domain in corresponding manner; thirdly, the estimated value is subtracted from the filtered signals, and the result is taken as the detecting result to output, and then is sent to the determiner in non-error control coding system to get the symbol hard determination output or is sent to the determiner in error control coding system to get the symbol soft determination output that finally sent to the coder. The method promotes the transmission rate and the anti-interference ability and advances the spectrum efficiency. | 12-17-2009 |
| 20090316844 | System and Method for Reducing Radio Frequency Interference from Digital Circuits - An information handling system includes a digital circuit having a first terminal connected to a first voltage reference, and a second terminal connected to a second voltage reference. The digital circuit is configured to be coupled to a radio device. The system also includes a band pass filter having a first terminal connected to the first voltage reference, and a second terminal connected to the second voltage reference. The bandpass filter is configured to produce a low impedance response, to reduce a radio frequency noise generated at a specific frequency band of the band pass filter, and to reduce a radio frequency interference produced by the digital circuit and received at the radio device. | 12-24-2009 |
| 20090323873 | Method for Discerning a Desired Signal from an Interfering Signal in an Under Sampled System - Described herein are methods and apparatuses for receiving a desired signal at a signal receiver with an undersampling frequency. A signal converter with a local oscillator frequency, a bandpass filter, and an analog-to-digital converter are used to generate an aliased discrete-time spectrum from an input analog spectrum. In order to determine the presence of interfering signals in the aliased discrete-time spectrum and, if present, separate a desired signal from the interfering signal, the local oscillator frequency is shifted. The original discrete-time spectrum and the resulting shifted discrete-time spectrum are both analyzed to select a local oscillator frequency that does not cause interference with the desired signal when the discrete-time spectrum is generated. The selected local oscillator frequency is then utilized to process the desired signal. | 12-31-2009 |
| 20090323874 | CHANNEL ESTIMATION USING COMMON AND DEDICATED PILOTS - The present invention relates to a receiver apparatus and method of channel estimation in a telecommunication system which provides at least two pilot sequences, and to a computer program product. Channel estimation is achieved by estimating channel taps separately for each of the at least two pilot sequences in every transmission block, and for applying estimated channel taps obtained from the estimation to at least one of a temporal and spatial filtering or combining operation to refine the channel estimate. Accordingly, temporal correlations and cross-correlations of the at least two pilot sequences are exploited without requiring knowledge of path delays and beamforming parameters. | 12-31-2009 |
| 20100002815 | DYNAMIC FILTERING FOR ADJACENT CHANNEL INTERFERENCE SUPPRESSION - A method for adjacent channel interference suppression comprises the steps of receiving a composite signal including a signal of interest and possibly one or more adjacent channel interferers, measuring the signal of interest and the possibly one or more adjacent channel interferers, and adjusting a location of at least one dynamic filter to extract the signal of interest. A receiver apparatus comprises an antenna configured to receive a composite signal including a signal of interest and possibly one or more adjacent channel interferers, an interference measurement circuit configured to measure the signal of interest and the possibly one or more adjacent channel interferers, at least one dynamic filter configured to extract the signal of interest, and a processor configured to adjust a location of at least one dynamic filter to extract the signal of interest. | 01-07-2010 |
| 20100002816 | METHOD AND APPARATUS FOR MULTIPLE SIGNAL IDENTIFICATION AND FINDING THE BASIS FUNCTIONS OF THE RECEIVED SIGNAL - A method is disclosed to detect a broad class of signals in Gaussian noise using higher order statistics. The method detects a number of different signal types. The signals may be in the base-band or the pass-band, single-carrier or multi-carrier, frequency hopping or non-hopping, broad-pulse or narrow-pulse etc. In a typical setting this method provides an error rate of 3% at a signal to noise ratio of 0 dB. This method gives the time frequency detection ratio which may be used to determine if the detected signal falls in Class Single-Carrier of Class Multi-Carrier. Additionally, this method may be used for a number of different applications such as multiple signal identification, finding the basis functions of the received signal. | 01-07-2010 |
| 20100034329 | TELEPHONE COMMUNICATIONS SYSTEM INCREASING A RECEPTION COUNT TWOFOLD - A telephone communications system includes a quantizing device quantizing a multifrequency signal at a sampling frequency which is twice or more as larger as a sampling frequency necessary for sampling the multifrequency signal to produce quantized data, a low-pass filter low-pass filtering the quantized data at a cutoff frequency higher than a maximum frequency of the multifrequency signal to produce low-pass filtered data, and a multifrequency signal receiver alternately performing an odd-numbered receiver processing and an even-numbered receiver processing on the low-pass filtered data. | 02-11-2010 |
| 20100040181 | APPARATUS AND METHOD FOR FILTERING NOISE IN IMAGE SIGNAL - An apparatus and a method for filtering noise in an image signal are provided. The apparatus includes an analog-to-digital converter (ADC), a first filter, and a second filter. The ADC receives the image signal and converts the image signal into a digital signal. The first filter receives the digital signal and filters a first noise portion of the digital signal to generate a first signal. The second filter coupled to the first filter receives the first signal and filters a second noise portion of the first signal, wherein the first noise portion is a sampled-based impulse noise, and the second noise portion is a line-based impulse noise. | 02-18-2010 |
| 20100046682 | ENHANCED GERAN RECEIVER USING CHANNEL INPUT BEAMFORMING - A method for suppressing interference in a wireless communication is provided. The method comprises receiving a burst of symbols, generating a plurality of timing hypotheses for the burst of symbols, and calculating, for each timing hypothesis, a plurality of weights for an interference suppression filter based upon a subset of the burst of symbols. The method further comprises, for each timing hypothesis, filtering the subset of the burst of symbols using the interference suppression filter with the corresponding plurality of weights, and selecting one of the plurality of timing hypotheses corresponding to a selection criteria. The method further comprises equalizing and decoding the filtered burst of symbols based upon the selected one of the plurality of timing hypotheses. | 02-25-2010 |
| 20100054380 | Refinement of Channel Estimation With a Bank of Filters - A receiver for acquiring a signal through a propagation channel, the receiver comprising channel estimating means ( | 03-04-2010 |
| 20100054381 | JOINT DEMODULATION FILTER FOR CO-CHANNEL INTERFERENCE REDUCTION AND RELATED METHODS - A joint demodulation filter for reducing co-channel interference between a desired signal and a co-channel interfering signal may include an input receiving samples of the desired signal and the co-channel interfering signal, a Viterbi decoder, and a first signal path between the input and the Viterbi decoder comprising a first filter. The joint demodulation filter may further include a second signal path between the input and the Viterbi decoder and comprising a linear finite impulse response (FIR) modeler for generating a channel impulse response estimate for the co-channel interfering signal. Additionally, a third signal path may be between the input and the Viterbi decoder and include a whitened matched filter for generating a channel impulse response estimate for the desired signal. | 03-04-2010 |
| 20100067630 | Variable Low IF Receiver for Multi-Channel Applications - Systems and methods for demodulating a plurality of contiguous channels contained within a bandlimited portion of a radio-frequency (RF) input signal are provided. In an embodiment, the bandlimited portion of the RF input signal is down-converted to baseband. After down-conversion, the bandlimited portion overlaps at baseband with a mirror image of the bandlimited portion. The plurality of contiguous channels within the down-converted signal similarly overlap at baseband and subsequently occupy a bandwidth substantially equal to half that required before down-converting. Image rejection is performed in the digital domain to recover each of the plurality of overlapping channels. | 03-18-2010 |
| 20100091920 | IMPROVING RECEIVER PERFORMANCE IN A COMMUNICATION NETWORK - Methods and apparatus are described for improving receiver performance in a multicarrier communication network in which an encoded symbol ( | 04-15-2010 |
| 20100098199 | POST-FILTER, DECODING DEVICE, AND POST-FILTER PROCESSING METHOD - Provided is a decoding device which suppresses generation of an abnormal sound caused by a layer switch. The decoding device includes: a first layer decoding unit ( | 04-22-2010 |
| 20100119021 | METHOD FOR DERIVING PARASITIC SIGNALS FROM MODULATED DIGITAL SIGNALS - A method for deriving interference signals from modulated, digital signals is provided. The receiver end reconstructs the modulated digital signals sent by a transmitter. These reconstructed modulated digital signals are then subtracted from the received modulated digital signals, and the result of the subtraction is used to estimate the interference signals without influence by prior filtering at the receiver end. By way of example, it is possible to demodulate the interference signals estimated at the receiver end in order to ascertain possible unauthorized carrier frequencies which disturb the regular carrier frequencies, even if the interference signals are not completely in the bandwidth of the regular carrier frequency or carrier frequencies. | 05-13-2010 |
| 20100119022 | CALIBRATION-FREE LOCAL OSCILLATOR SIGNAL GENERATION FOR A HARMONIC-REJECTION MIXER - A circuit for producing multiple switching control signals for a harmonic rejection mixer from multiple phases of a digital local oscillator signal is presented, wherein a first waveform combiner circuit is arranged to generate from the multiple phases of the digital local oscillator signal at least one switching control signal by logical combining two from the multiple phases of a digital local oscillator signal, and a second waveform combiner circuit is arranged to generate from the multiple phases of the digital local oscillator signal at least one first switching control signal by logical combining one from the multiple phases of a digital local oscillator signal with a predetermined signal having a static logical value. To compensate for phase errors the schematic topology of the first and the second waveform combiner circuit are arranged to be fully symmetrical to each other in that in the first waveform combiner, the circuit part for providing the function of the second waveform combiner is used as a dummy circuit, and in the second waveform combiner, a circuit part for providing the function of the first waveform combiner is used as a dummy circuit. Accordingly, the sources for providing the multiple phases of the digital local oscillator signal see the same load, and hence required phase shift is guaranteed. | 05-13-2010 |
| 20100135446 | DIGITAL-INTENSIVE RF RECEIVER - A digital-intensive RF receiver including: a first filter unit configured to allow an RF signal of a pre-set frequency band among RF signals to pass therethrough; a low noise amplifier (LNA) configured to amplify the RF signal from the first filter unit such that the RF signal has a pre-set magnitude; a second filter unit configured to allow an RF signal of a pre-set frequency band among RF signals from the LNA to pass therethrough; a clock generation unit configured to generate a pre-set reference frequency signal and generate a sub-sampling clock having a pre-set frequency lower than an RF carrier frequency by using the reference frequency signal; a sub-sampling A/D conversion unit configured to A/D-convert the RF signal from the second filter unit into a digital signal according to the sub-sampling clock from the clock generation unit, divide the RF signal into a plurality of frequency bands and sub-sample them during the A/D conversion process and perform noise shaping by the sub-channels included in the RF signal; and a digital processing unit configured to process a digital signal from the sub-sampling A/D conversion unit according to a system clock generated by using the reference frequency signal from the clock generation unit. | 06-03-2010 |
| 20100158175 | METHOD AND APPARATUS FOR FILTERING NOISY ESTIMATES TO REDUCE ESTIMATION ERRORS - Techniques for filtering noisy estimates to reduce estimation errors are described. A sequence of input values (e.g., for an initial channel impulse response estimate (CIRE)) is filtered with an infinite impulse response (IIR) filter having at least one coefficient to obtain a sequence of output values (e.g., for a filtered CIRE). The coefficient(s) are updated based on the sequence of input values with an adaptive filter, a bank of prediction filters, or a normalized variation technique. To update the coefficient(s) with the adaptive filter, a sequence of predicted values is derived based on the sequence of input values. Prediction errors between the sequence of predicted values and the sequence of input values are determined and filtered to obtain filtered prediction errors. The coefficient(s) of the IIR filter are then updated based on the prediction errors and the filtered prediction errors. | 06-24-2010 |
| 20100158176 | CHANNEL ESTIMATION FOR WIRELESS COMMUNICATION - Techniques for deriving channel estimates with different channel estimation filters are described. In one scheme, a filter selection metric is determined for a signal to be recovered, a channel estimation filter is selected based on the filter selection metric, and a channel estimate is derived with the selected channel estimation filter. In another scheme, a first channel estimate is derived with a first channel estimation filter having a first filter response, a first signal is recovered with the first channel estimate, and interference due to the first signal is estimated and removed. A second channel estimate is derived with a second channel estimation filter having a second filter response that is different from the first filter response. | 06-24-2010 |
| 20100166126 | OFDM RECEPTION DEVICE, OFDM RECEPTION INTEGRATED CIRCUIT, OFDM RECEPTION METHOD, AND OFDM RECEPTION PROGRAM - An OFDM reception apparatus is provided that effectively suppresses a reduction in reception performance during high-speed mobile reception, thereby making it possible to achieve stable and high-speed mobile reception. To achieve this, the OFDM reception apparatus includes a transmission channel characteristic estimating unit for calculating a transmission channel characteristic value indicating phase and amplitude distortions in an OFDM signal for each sub-carrier, the phase and amplitude distortions occurring during propagation through a transmission channel, and calculating an n-th differentiation of the transmission channel characteristic value, and an interference component removing unit for using the transmission channel characteristic value and the n-th differentiation calculated for each of the sub-carriers by the transmission channel characteristic estimating unit, to remove an interference component between the sub-carriers from the OFDM signal. The transmission channel characteristic estimating unit performs a filtering process in a symbol direction with respect to the transmission channel characteristic value calculated for each of the sub-carriers to perform oversampling at intervals each smaller than a one-symbol interval, and uses transmission channel characteristic values existing in intervals each smaller than a two-symbol interval of the transmission channel characteristic values obtained by the oversampling to calculate the n-th differentiations. | 07-01-2010 |
| 20100177857 | INTERFERENCE IN COMMUNICATION DEVICES - A wideband signal comprising both a wanted signal and narrowband interference is received in a wideband receiver. The receiver comprises an interference detection unit comprising a set of sub-band filters. With the aid of the sub-band filters the received signal is processed to detect a sub-band containing the narrowband interference in time domain. | 07-15-2010 |
| 20100183106 | SYSTEM AND METHOD FOR COMPENSATING FOR NONLINEAR INTERFERENCE CANCELLATION IN MULTI-CARRIER TRANSMISSION - An aspect of the present invention is drawn to a receiver operable to receive a first signal transmitted on a first carrier and to receive a second signal transmitted on a second carrier. The receiver includes a first filter, a second filter and a nonlinear compensator. The first filter is arranged to receive the first signal and to generate a first filtered signal. The second filter is arranged to receive the second signal and to generate a second filtered signal. The nonlinear compensator is arranged to output a first compensating signal based on the first filtered signal and the second filtered signal and to output a second compensating signal based on the first filtered signal and the second filtered signal. Further, the nonlinear compensator can reduce one of nonlinear interference within the first filtered signal and nonlinear interference between the first filtered signal and the second filtered signal. | 07-22-2010 |
| 20100189205 | RECEIVER CIRCUIT, RECEPTION METHOD, AND COMMUNICATION SYSTEM - A receiver circuit includes an LPF configured to remove an interference signal and/or a noise from a received signal, an ADC configured to digitize a signal output from the LPF, an FIR filter configured to further remove an interference signal and/or a noise from the signal output from the ADC and compensate imperfection in in-band characteristics caused in the LPF, a delay circuit configured to delay the signal output from the ADC by a predetermined time period, and a control circuit configured to control a destination of the signal output from the ADC, wherein the control circuit switches the destination of the signal output from the ADC to one of the FIR filter and the delay circuit according to a predetermined condition. | 07-29-2010 |
| 20100195775 | COMMUNICATIONS DEVICE INCLUDING A FILTER FOR NOTCHING WIDEBAND RECEIVE SIGNALS AND ASSOCIATED METHODS - A communications device includes pre-processing circuitry for processing a received wideband complex signal including an undesired narrowband interference component therein, and for determining a frequency of the undesired narrowband interference component. A filter is downstream from the pre-processing circuitry and operable to generate a received wideband complex signal with at least one frequency notch therein to suppress the undesired narrowband interference component. The filter includes a finite impulse response (FIR) filter with L taps to generate N output values, with L>N. A Fast Fourier Transform (FFT) block is downstream from the FIR filter and has a length N so that filter transition regions occur between frequency bins of the FFT block. A notching block is downstream from the FFT block to generate the frequency notch. An Inverse Fast Fourier Transform (IFFT) block is downstream from the notching block and has the length N. | 08-05-2010 |
| 20100232556 | JOINT SPACE-TIME OPTIMUM FILTERS (JSTOF) FOR INTERFERENCE CANCELLATION - A filter for reducing co-channel interference within a communications receiver may include a multi-channel, space-time filter circuit that filters n signal parts that have been split from a communications signal by jointly estimating space-time filter weights and multi-channel impulse responses (CIRs). The filter may further include a multi-channel, matched filter circuit that receives multi-channel signals from the multi-channel, space-time filter circuit and has a filter response that is provided by a channel impulse response estimation from the space-time filter circuit. | 09-16-2010 |
| 20100260295 | FILTER CIRCUIT, AND RECEIVER AND ELECTRONIC DEVICE USING THE SAME FILTER CIRCUIT - Filter circuit includes Nth-order active filters switching circuit which switches shorting or non-shorting of active filter, and power-supply control circuit which controls such that a power supply of active filter is turned off when switching circuit shorts active filter. A receiver employing filter circuit turns off the power supply of active filter not needed when no interference wave exists within a given range from a desired frequency band. The foregoing structure allows lowering the power consumption of filter circuit. | 10-14-2010 |
| 20100303183 | Direct detection of wireless interferers in a communication device for multiple modulation types - Direct detection of wireless interferers in a communication device for multiple modulation types. One or more radios implemented within a communication device is/are operative to receive and process wireless communications. A wireless communication signal is processed to extract symbols there from. Various symbols groups are processed in accordance with correlation processing to identify potential interferers (e.g., other communication devices using common portions of frequency spectra). Alternatively, matched filter processing (e.g., using a Barker matched filter in some embodiments) operates on the various symbol groups to identify some potential interferers. Various combinations of correlation processing and matched filter processing may be employed in other instances (e.g., using any of a desired means of comparison, combining, etc.) in considering interferers identified in accordance with each of these two means. Also, re-identification and re-characterization of possible interferers may be performed subsequently to remove or re-admit frequency spectra for use in communications. | 12-02-2010 |
| 20100310026 | ITERATIVE INTERFERENCE CANCELLATION RECEIVER - A method for suppressing interference in a wireless communication comprises receiving a burst of symbols, filtering the burst of symbols using an interference suppression filter with a first plurality of weights, decoding the filtered burst of symbols to generate data corresponding to the burst of symbols, encoding the data to generate a re-encoded burst of symbols, calculating a second plurality of weights for the interference suppression filter based upon the re-encoded burst of symbols, filtering the re-encoded burst of symbols using the interference suppression filter with the second plurality of weights, and decoding the filtered re-encoded burst of symbols. | 12-09-2010 |
| 20100310027 | METHOD AND SYSTEM FOR CHANNEL EQUALIZATION - One embodiment includes a method of receiving a transmitted signal. The method comprises receiving a signal transmitted over a channel. The signal comprises a known signal and an information signal. The method further includes determining at least one indicator of channel characteristics based at least in part on the portion of the known signal. The method further includes generating a first value indicative of the information signal based at least in part on the at least one indicator of the channel characteristics. The first value comprises an error signal. The method further comprises removing the error signal from the first estimate of the signal based at least in part on the portion of the known signal. Other embodiments include systems for performing the method and methods of making such systems. | 12-09-2010 |
| 20100322364 | Noise Filtering Inverse Transformation - A method, system and apparatus for noise filtering inverse transformation (NFIT), recovering phases and amplitudes of singular cycles of data carrying tones or sub-bands from a composite signal such as OFDM, is presented herein. Such NFIT comprises adaptive inverse transformation of non-linear channel transform function and instant accommodation of time variant quickly changing characteristics of transmission channel caused by interferences including line loads, cross-talk or predictable noise. | 12-23-2010 |
| 20110002428 | APPARATUS AND METHOD FOR REDUCING THIRD-ORDER INTERMODULATION DISTORTION - A method and apparatus for compensating for third-order intermodulation (IM) distortion in a receiver by passing a received signal through a detector to obtain a second-order difference signal, combining the 2nd-order signal with the received signal in a multiplier to obtain a 3rd-order IM signal, adjusting a parameter such as amplitude, phase or quadrature amplitude of the 3rd-order IM signal, and coupling the 3rd-order IM signal into the received signal. | 01-06-2011 |
| 20110013736 | SAMPLING FILTER DEVICE - A sampling filter device wherein the filter characteristic is variable without using a control signal of a complicated waveform is provided. A sampling filter device | 01-20-2011 |
| 20110019785 | Alignment of channel filters for multiple-tuner apparatuses - Apparatuses, systems, and methods that align channel filters for dual tuners are disclosed. An embodiment may comprise an IC having two tuners. Each tuner may have a low-noise amplifier, a mixer with a local oscillator, and channel filter. To perform a channel filter alignment, a bandwidth controller may cross-couple the local oscillator of each tuner to the input of the mixer of the opposite tuner. The bandwidth controller may adjust the frequencies of the local oscillators to produce different configuration tone frequencies at the outputs of the mixers, which are inputs to the channel filters. The bandwidth controller may then determine an amplitude difference between two separate measurements of a channel filter output and, based on a comparison of the measurements with predicted values, increment or decrement the filter bandwidth for each tuner and store parameters for the channel filters which create the largest signal amplitudes. | 01-27-2011 |
| 20110019786 | PROCESSING RECEIVED DIGITAL DATA SIGNALS BASED ON A RECEIVED DIGITAL DATA FORMAT - An integrated circuit radio receiver includes radio frequency (“RF”) front-end circuitry to receive a wireless signal and to produce digital data. The integrated circuit radio receiver includes a baseband processor is operable to process the digital data, in which the baseband processor is operable to produce a format designation based on the digital data. The baseband processor includes a plurality of digital filtering logic in which each of the digital filtering logic includes a level of digital filtering. The baseband processor further includes logic operable to select between each digital filtering logic of the plurality of digital filtering logic based upon the format designation, and to process the digital data with the selected level of digital filtering. | 01-27-2011 |
| 20110044413 | Method circuit and system for adapting a receiver receive chain based on detected background noise - Disclosed is a radio frequency (RF) receiver for receiving a communication channel modulated on one or more carrier frequencies. The receiver may include a gain adjustable RF amplifier, a wideband signal power measurement circuit, and control logic. The control logic may be adapted to use outputs of one or more measurement circuits to classify interfering signals based on measured signal power and spectral proximity to the one or more channel carrier frequencies, and to adjust the gain of the radio frequency amplifier based on the classification. | 02-24-2011 |
| 20110044414 | Mitigating Radio Receiver Multipath Noise - In one embodiment, a method for processing radio frequency signals includes estimating an average value of a demodulated signal and a noise signal, both obtained from a radio frequency signal, estimating a noise floor based on the noise signal, generating a blend control signal based on the average values and the noise floor, and blending at least two path signals based on the blend control signal to obtain a blended signal. This blended signal may be output for further processing when multipath noise is detected. | 02-24-2011 |
| 20110044415 | ADAPTIVE INTEGRATED HYBRID WITH COMPLEX ADAPTATION FOR DIGITAL SUBSCRIBER LINE SYSTEMS - An adaptive hybrid system is coupled to a loop for adjusting trans-hybrid loss. The system comprises a fixed portion comprising a first receiver transfer function block and a first hybrid transfer function block. The fixed portion is configured to receive a far-end signal and mitigate frequency dependent attenuation experienced by the far-end signal. The system also comprises a variable portion comprising a second receiver transfer function block and a second hybrid transfer function block configured to subtract a transmit echo from the received far-end signal. | 02-24-2011 |
| 20110051867 | METHODS AND APPARATUS FOR WIRELESS CHANNEL ESTIMATION USING INTERPOLATION ELIMINATION IN THE EIGEN DOMAIN - Methods and apparatus are provided for wireless channel estimation using interpolation elimination in the Eigen domain. Channel components at known OFDM symbol locations are interpolated to other OFDM symbol locations. Methods and apparatus are provided for interpolating in the Eigen domain between reference signals (i.e., training signals) to estimate the equalizer coefficients with a reduced complexity. In particular, one aspect of the present invention performs the required interpolation before a required matrix inversion in the Eigen domain. | 03-03-2011 |
| 20110051868 | VARIOUS IMPEDANCE FM RECEIVER - A receiver within a wireless device is able to couple to different antennas with different impedances. The wireless device includes a first antenna pin for coupling to a first antenna with a first impedance, a second antenna pin for coupling to a second antenna with a second impedance and a switch for selecting at least one of the first antenna and the second antenna to couple to the receiver. | 03-03-2011 |
| 20110051869 | RECEIVING APPARATUS AND RECEIVING METHOD - A receiving apparatus includes: RF filters for selecting and outputting a signal to be down-converted from among a plurality of received signals having different bands; a phase conversion unit for generating a phase difference between output signals of the filters and down-converting the output signals of the filters to output a plurality of sample signals; a quantization unit for converting the plurality of sample signals from discrete signals into digital signals; and a signal separation unit for separating and outputting each of a plurality of output signals corresponding to the plurality of received signals from the output signals of the quantization unit by using a phase shift value caused by the phase difference. | 03-03-2011 |
| 20110064174 | COMMUNICATION DEVICE AND RECEIVING METHOD THEREOF - A communication device and receiving method thereof are disclosed in embodiments of the present invention. The communication device includes an extra digital to analog converter, an inverse partial response filtering circuit and an analog to digital converter. The extra digital to analog converter receives a first digital signal and generates a pulse shaped analog signal. The inverse partial response filtering circuit receives a first difference signal, and adjusts a response of the inverse partial response filtering circuit to generate an adjusted signal, wherein the first difference signal equals the result of subtracting the pulse shaped analog signal from a receiving signal. The analog to digital converter converts the adjusted signal to generate a second digital signal. | 03-17-2011 |
| 20110064175 | METHODS AND AN APPARATUS FOR ESTIMATING A RESIDUAL FREQUENCY ERROR IN A COMUNICATIONS SYSTEM - The present invention relates to methods and an apparatus for estimating a residual frequency error. According to an embodiment, an expected vector for selected subcarriers of a received symbol is estimated using a channel estimate vector and a reference vector; a sampling frequency mismatch is removed and a dot product is calculated using the expected and a received vector. An angle of the product is estimated and a change in angle from a previous symbol is calculated. The residual frequency is estimated using the calculated change in angle. In another embodiment, an expected subcarrier is estimated based on a channel estimate and on a reference subcarrier, an angle and magnitude of the multiplication between the expected and a received subcarrier are estimated; a phase offset is removed; a weighted mean value of the angles is calculated and the residual frequency error is estimated using a change in weighted mean angle. | 03-17-2011 |
| 20110069797 | RECEIVING DEVICE AND METHOD THEREOF - A receiving device includes: a mixer module arranged to receive an input signal to generate a down-converted output; a first active filter, the first active filter arranged to receive the down-converted output and perform an active filtering process upon the down-converted output to generate a first filtered output; a passive filter, the passive filter arranged to receive the first filtered output and perform a passive filtering process upon the first filtered output to generate a second filtered output; and a processing circuit, the processing circuit arranged to receive the second filtered output and process the second filtered output to generate an output signal corresponding to the input signal. | 03-24-2011 |
| 20110069798 | Impulse noise mitigation under out-of-band interference conditions - A noise abatement method and system for impulse noise in an RF receiver where the RF analog signal is converted to a digital signal prior to being connected to a demodulator. Two filters are used to detect impulse noise signals even under out-of-band interferer conditions, and prevent the impulse noise from reaching the input to the demodulator. A first of the two filters detects impulse noise using signals lower than the frequency bandwidth of the desired signal, and a second of the two filters detects impulse noise using signals higher the frequency bandwidth of the desired signal. A mean magnitude of the signal is detected over a predetermined time T and is used to select which filter to use for noise abatement. | 03-24-2011 |
| 20110075774 | METHOD AND APPARATUS FOR MITIGATION OF INTERFERENCE - A signal is provided to each of nominal, higher and lower primary filters in a receiver. The nominal, higher and lower primary filters have different center frequencies and a bandwidth B1 and bandwidths B2, respectively and a bandwidth offset B0, with B2=B1+B0. Signal recovery is performed on the output of each primary filter to obtain recovered signals and error values each associated with one of the primary filters. Each error value is provided to a secondary and tertiary filter, to generate a signal criterion, and whose output is measured to generate a quality metric, respectively, associated with each recovered signal. The recovered signal associated with the nominal primary filter and any other recovered signal having an associated signal criterion below a threshold value is selected and the selected recovered signal which has the lowest associated quality metric is chosen. | 03-31-2011 |
| 20110075775 | ANALOG TO DIGITAL CONVERTER WITH LOW OUT OF BAND PEAKING - An analog to digital converter includes a delta sigma modulator with a modified distributed feed-forward (DFF) topology. The modulator includes low pass filter circuitry that provides a first path to a first integrator and a second, feed-forward path to a second integrator that significantly reduce the out of band signal transfer function (STF) peaking of the modulator. | 03-31-2011 |
| 20110075776 | Method and circuit for digitally filtering a signal - A method and circuit that gives a sequence pattern that represents directions of positive and negative transitions of the phase that continue over a predetermined number from a certain reference symbol to an adjoining next reference symbol; finds (heuristically) one or more interpolate symbols that meet conditions (such as standards for power spectra) of a predetermined frequency spectrum, i.e., band, and a predetermined (range of) amplitude with reference to the given sequence pattern; and stores the found sequence pattern and a phase value and an amplitude value corresponding to the found one or more interpolate symbols in a memory as a lookup table against the prepared memory area. | 03-31-2011 |
| 20110075777 | Phase-Locked Loop Based Controller for Adjusting an Adaptive Continuous-Time Filter - A direct conversion radio-frequency (RF) receiver includes a controller and an adaptive continuous-time filter. The adaptive continuous-time filter receives a multiple-bit control signal generated by the controller to adjust a characteristic of the continuous-time filter. The controller generates the multiple-bit control signal in response to process variation in the semiconductor material used to implement the controller and the adaptive continuous-time filter. A method for tuning an adaptive continuous-time filter comprises determining a RC time constant, converting the RC time constant to a digital word, comparing a select bit of the digital word to a respective bit of a predetermined reference word to generate a control bit, applying the control bit to an adjustable element to modify the RC time constant, repeating the determining, converting, comparing and applying steps until the control bits generate an output word and providing the output word to the adaptive continuous-time filter. | 03-31-2011 |
| 20110085628 | ADAPTIVE DATA DEPENDENT NOISE PREDICTION (ADDNP) - A method is provided. The method comprises calibrating noise prediction parameters by adapting one or more biases, adapting one or more filter coefficients using the adapted one or more biases, and adapting one or more prediction error variances using the adapted one or more biases and the adapted one or more filter coefficients. | 04-14-2011 |
| 20110085629 | Methods, Devices and Systems for Processing a Signal in the Presence of Narrowband Interference - A method is disclosed for processing a received signal in the presence of an interference of a first type within the bandwidth of a desired signal of the received signal. The method comprises filtering the received signal using at least a first filter having at least a first filter characteristic to produce a filtered signal wherein the interference of the first type is suppressed. Furthermore, the method comprises determining a desired data stream from the filtered signal, basing the determination at least on the first filter characteristic. A method is also disclosed for processing a signal where the method comprises receiving an indication of whether interference of a first type is present in a frequency interval within the bandwidth of the signal, filtering the signal using at least a first filter having at least a first filter characteristic to produce a filtered signal wherein the filtered signal is suppressed in the frequency interval; and transmitting the filtered signal. Corresponding devices, systems and computer program products are also disclosed. | 04-14-2011 |
| 20110096878 | Delta-Sigma Analog-to-Digital Converter, Radio Receiver, Communication Apparatus, Method, and Computer Program - A delta-sigma analog-to-digital converter (ADC) is disclosed. The ADC comprises a forward path structure; a feedback structure; and a first subtraction element arranged to receive an input signal to the delta-sigma analog-to-digital converter and a feedback signal from the feedback structure and output a difference signal, which is a difference between the input signal and the feedback signal, to the forward path structure, wherein the forward path structure comprises a quantizer arranged to convert an analog input signal to a digital representation; a forward path filter arranged to input the difference signal and provide an output signal to the quantizer, and the feedback structure comprises a first and a second branch, wherein the first branch comprises a first digital-to-analog converter arranged to provide output signals to the subtraction element; and a first feedback filter having a gain to frequency characteristic such that frequencies that are desired in the analog-to-digital conversion, compared to undesired frequencies, are attenuated in the feedback structure, and the second branch comprises a second digital-to-analog converter, wherein the first and second branches are fed by the digital representation and the outputs of the first and second branches are merged in a second subtraction element arranged to output a signal, which is a difference between the signals from the first and second branches, to the first subtraction element. A radio receiver, communication apparatus, method for analog-to-digital conversion, and computer program for implementing the method are also disclosed. | 04-28-2011 |
| 20110096879 | FILTER PROCESSING DEVICE AND SEMICONDUCTOR DEVICE - The present invention provides a technique for changing the number of taps in filter processing without the need for execution of branch processing. A filter processing device comprises: an arithmetic circuit that performs arithmetic processing for filtering operation; an internal register that retains data to be subjected to arithmetic processing in the arithmetic circuit and that receives the result of arithmetic processing from the arithmetic circuit as data to be written back thereto; and a data generator that generates data to be fed to the arithmetic circuit through use of the data retained in the internal register. Further, in the filter processing device, there is disposed a tap number control circuit that is capable of controlling the number of taps in filter processing according to a tap control signal applied thereto. In this configuration, no branch processing is required for controlling the number of taps by the use of the tap number control circuit. | 04-28-2011 |
| 20110103532 | METHOD AND SYSTEM FOR USING A MULTI-RF INPUT RECEIVER FOR DIVERSITY SELECTION - A method for processing signals in a receiver includes receiving a plurality of wireless signals via a plurality of M receive antennas coupled to M corresponding signal amplifiers. The method may also include measuring corresponding signal strengths of M signals generated when each of M phase-shifters is coupled to each of the M receive antennas, while one or more of the M signal amplifiers are disabled. One of the M generated signals may be selected for processing without the use of an antenna switch, where the selecting may be based on the measured signal strength. Each of the plurality of received wireless signals may be amplified prior to the measuring. One or both of an in-phase (I) component and/or a quadrature (Q) component may be generated for each of the M generated signals. | 05-05-2011 |
| 20110110473 | DIGITAL AND ANALOG IM3 PRODUCT COMPENSATION CIRCUITS FOR AN RF RECEIVER - Third-order intermodulation products (IM3) are attenuated in RF receivers by providing a typical main signal path and a parallel auxiliary signal path in which the IM3 products are accentuated, and the output from the main signal path is adaptively filtered to attenuate the IM3 products. In one embodiment, a multirate filter bank (MRFB) with asymmetric analysis and synthesis sections is used to detect and isolate the IM3 products. In another embodiment an analog nonlinear term generator is placed at the front of the auxiliary signal path. The analog nonlinear term generator takes advantage of the nonlinearities of a differential MOSFET circuit and a multiplier to extract the IM3 products in the RF input signal. The outputs of the main signal path and the auxiliary signal path are inputs to a complex least mean squares filter to attenuate the IM3 products in the resulting signal. | 05-12-2011 |
| 20110116584 | Fault-Aware Matched Filter and Optical Flow - In one embodiment, a fault-aware matched filter augments the output of a component matched filter to provide both fault-aware matched filter output and a measure of confidence in the accuracy of the fault-aware matched filter output. In another embodiment, an optical flow engine derives, from a plurality of images, both optical flow output and a measure of confidence in the optical flow output. The measure of confidence may be derived using a fault-aware matched filter. | 05-19-2011 |
| 20110116585 | METHOD AND APPARATUS FOR ADAPTIVE NOISE AND/OR SIGNAL FILTERING IN AN HSDPA CHANNEL QUALITY INDICATOR (CQI) SELECTION - Methods and systems for processing signals in a wireless communication system are disclosed. Aspects of the method may include estimating at a receiver, a rate at which a communication channel changes. A length of a filter used to average a noise power estimate and/or a signal power estimate may be adaptively changed based on the estimation of the rate at which the communication channel changes. The communication channel may comprise a common pilot channel (CPICH). At least a portion of a wireless signal received via the communication channel may be descrambled at the receiver to generate a plurality of descrambled bits. At least a portion of the plurality of descrambled bits may be accumulated to generate at least one in-phase (I) component and at least one quadrature (Q) component. | 05-19-2011 |
| 20110129047 | RECEPTION DEVICE AND RECEPTION METHOD - It is possible to reduce the effect of an interference signal while suppressing increases in a circuit scale and a processing time. A reception device receives a multicarrier signal and an interference signal via a radio transmission path, detects a frequency position of the interference signal, performs filtering to suppress the multicarrier signal and the interference signal at the detected frequency position of the interference signal, removes a guard interval from the multicarrier signal suppressed by the filtering, demodulates each subcarrier of the multicarrier signal from which the guard interval is removed, and performs error correction on the demodulated signal. | 06-02-2011 |
| 20110135045 | WIDEBAND RECEIVER - Provided is a wideband receiver that has a smaller area and consumes less power and can prevent harmonic mixing occurring due to an increase in the number of communications systems using wideband. A wideband receiver according to an aspect of the invention may include: an front-end unit receiving and performing low-pass filtering on a wideband input signal in a continuous-time domain; and a down-conversion unit sampling and holding an output signal of the front-end unit according to a local oscillator signal and performing low-pass filtering on the output signal in a discrete tie domain. | 06-09-2011 |
| 20110150154 | HYBRID CORRELATION AND LEAST SQUARES CHANNEL ESTIMATION - A hybrid channel estimator for a wireless communication system receiver includes both correlation based and least squares based channel estimators. The correlation estimator is used when signal quality is low or noise is colored. The least squares estimator is used when signal quality is high or noise is white. An interference suppression filter improves signal quality by suppressing interference in a received signal. Generally, correlation channel estimation is performed initially, when signal quality is low and noise is colored, and interference suppression filtering is performed to increase signal quality by removing certain portion of interference and whitening the overall impairment spectrum. These may be done iteratively. When the signal quality improves, least squares channel estimation is performed, which may also be iterative. The training sequence and noise may be whitened prior to performing least squares channel estimation, which is the final operation before channel estimates are forwarded to a demodulator. | 06-23-2011 |
| 20110150155 | IN-BAND INTERFERENCE REJECTION OF SIGNALS IN ALTERNATE AND ADJACENT CHANNELS - A method includes filtering a received signal to generate a band-pass filtered signal using a band-pass filter having a pass-band including frequencies located within a central lobe of a power spectrum associated with a target channel of a plurality of channels supported by a communications system. The pass-band is approximately centered at a frequency of a null of a power spectrum associated with at least one other channel of the plurality of channels supported by the communications system. The method includes processing the received signal based on the band-pass filtered signal. The at least one other channel may include at least one of an alternate channel and an adjacent channel of the plurality of channels. | 06-23-2011 |
| 20110158363 | Method for Determining Updated Filter Coefficients of an Adaptive Filter Adapted by an LMS Algorithm with Pre-Whitening - The application relates to a method for determining at least one updated filter coefficient of an adaptive filter ( | 06-30-2011 |
| 20110170643 | COMPLEX SIGNAL PROCESSING CIRCUIT, RECEIVER CIRCUIT, AND SIGNAL REPRODUCTION DEVICE - An analog complex filter combines an in-phase signal and a quadrature signal to output first and second analog signals. An analog-to-digital converter converts the first and second analog signals into first and second digital signals. A first digital complex filter attenuates a component corresponding to the quadrature signal of the first digital signal and outputs the resultant signal as a third digital signal, and attenuates a component corresponding to the in-phase signal of the second digital signal and outputs the resultant signal as a fourth digital signal. An IQ imbalance correction circuit corrects a quadrature error and an amplitude error between the third and fourth digital signals. | 07-14-2011 |
| 20110194657 | SUBSAMPLING BASED RECEIVER USING FREQUENCY SELECTIVE NOISE CANCELLER - Provided is a frequency selective noise canceller including: a frequency selective single to differential converter having a band pass filter function, converting a received single input signal into a differential signal in a wanted signal pass frequency band and into a common mode signal in an unwanted signal frequency band; and a common mode rejector functioning as a load having an arbitrary impedance with respect to the differential signal outputted from the frequency selective single to differential converter and functioning as a filter with respect to the common mode signal. | 08-11-2011 |
| 20110194658 | DIGITAL FRONT-END STRUCTURE OF SUB-SAMPLING BASED DIGITAL RECEIVER - Provided is a digital receiver for use in a wireless communication transmitting/receiving system. The digital receiver oversamples a desired-band signal during performing a subsampling operation for converting an RF signal into an IF signal or DC signal so that an unwanted signal is also converted into a digital signal, and then, eliminated in a digital block. | 08-11-2011 |
| 20110200152 | Continuous Time Analogue/Digital Converter - Continuous time analogue/digital converter, comprising a sigma delta modulator (MSD | 08-18-2011 |
| 20110206171 | Interference Suppression Processing Unit and a Method of Suppressing Interference in Wireless Data Communication - An interference suppression processing unit includes at least one receive path, wherein each of the at least one receive path is configured to transmit one of at least one received data sequence received from at least one antenna port, a signal generation unit configured to generate at least one signal data sequence from the at least one received data sequence, at least one signal path, wherein each of the at least one signal path is configured to transmit one of the at least one signal data sequence, at least one prefilter unit, wherein each of the at least one prefilter unit is coupled to one of the at least one signal path and a combiner including at least one input terminal, wherein each of the at least one input terminal is connected to an output terminal of one of the at least one prefilter unit, wherein the signal generation unit is configured to generate K1 first signal data sequences, wherein each first signal data sequence is identical to one of the at least one received data sequence, respectively, and K2 second signal data sequences, wherein each second signal data sequence is not identical to one of the at least one received data sequence, respectively, and wherein the number of the first signal data sequences and the second signal data sequences (K1+K2) equals the number of the at least one signal data sequence. | 08-25-2011 |
| 20110228884 | METHOD AND DEVICE FOR FILTERING CHANNEL ESTIMATION RESULT IN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING - The invention provides a method and device for filtering orthogonal frequency division multiplexing (OFDM) channel estimate result, to solve the problems in the prior art that for channel estimate result filtering the realization is complex or the performance is poor. By embodiments the following method is described: transforming time domain synchronous symbols received by the terminal equipment to frequency domain synchronous symbols; computing frequency domain impulse response sequences based on the frequency domain synchronous symbols; adjusting least mean square (LMS) adaptive filter coefficients based on the frequency domain impulse response sequences; obtaining coefficients of the data symbol channel estimate result frequency domain filter based on the coefficients obtained from said adjusting; filtering the OFDM channel estimate result by using the data symbol channel estimate result frequency domain filter. The corresponding device is disclosed by the embodiments. There is less computation, simpler realization and better filtering performance provided with the OFDM channel estimate result frequency domain filter obtained from the technical solution of the present invention. | 09-22-2011 |
| 20110235761 | Method circuit and system for received signal noise reduction or cancellation - Disclosed are methods, circuit and devices for received signal noise reduction of cancellation. There is provided a first and a second antenna spatially separated from one another. A noise extractor may generate a signal indicative of noise received at the second antenna, and a channel estimator may estimate one or more parameters of a channel between the first and the second antennas. A filter may modify the signal indicative of noise received at the second antenna using the one or more estimated channel parameters to generate a signal estimating noise received at said first antenna. A signal subtracting module may subtract from a signal received at the first antenna the signal estimating noise received at said first antenna. | 09-29-2011 |
| 20110243286 | INFRARED RECEIVER CIRCUIT - The invention relates to an infrared receiver circuit for receiving a carrier-modulated infrared signal that comprises a carrier signal and a wanted signal modulated onto the carrier signal, having a band pass filter that exhibits a frequency adjustment connection via which the band center frequency of the band pass filter can be adjusted, furthermore having a demodulator for recovering the wanted signal and having a signal output to which the demodulated wanted signal can be output. The infrared receiver circuit exhibits a signal input that is at least indirectly connected to the frequency adjustment connection of the band pass filter so that the band center frequency of the band pass filter can be adjusted by a clock signal of an external clock pulse generator. | 10-06-2011 |
| 20110243287 | RECEIVER APPARATUS, IMAGE SIGNAL ATTENUATING METHOD, AND MISMATCH COMPENSATING METHOD - To improve the degree of removal of unwanted component signals with a small area while eliminating the need for a high-frequency signal source. IF band simulated image signals IM-I, IM-Q output from an IF band simulated image signal generating unit ( | 10-06-2011 |
| 20110261912 | Performing Impulse Blanking Based On Blocker Information - One aspect of the present invention is directed to an apparatus to perform impulse blanking of a received signal at multiple locations of a signal processing path. To effect such impulse blanking, multiple impulse detectors and blankets may be present, in addition to other circuitry. The impulse detectors may operate at different bandwidths, and the impulse blankers may be located at different locations of the signal processing path and may be differently configured. | 10-27-2011 |
| 20110261913 | FRACTIONAL FREQUENCY AND SAMPLING-RATE CHANGE IN THE FREQUENCY DOMAIN - An arrangement ( | 10-27-2011 |
| 20110280352 | FIXED POINT FIR FILTER WITH ADAPTIVE TRUNCATION AND CLIPPING AND WIRELESS MOBILE STATION USING SAME - A fixed point finite impulse response (FIR) filter comprising: 1) an input stage for receiving an input signal as a sequence of input samples comprising: i) delay elements connected in series for receiving and shifting N sequential input samples; ii) multipliers, each multiplier receiving a selected one of the N sequential input samples from the delay elements and multiplying the selected input sample by a corresponding coefficient to produce an intermediate product; and iii) a summer for receiving and adding N intermediate products from the multipliers to produce an output sum signal comprising a sequence of output sum samples; and 2) an output stage for truncating k least significant bits (LSBs) from each of the output sum samples, wherein k is a variable number. | 11-17-2011 |
| 20110293053 | TIME-DOMAIN EQUALIZATION FOR DISCRETE MULTI-TONE SYSTEMS - A multiple carrier communication system includes a primary impulse shortening filter that receives an output signal of an analog to digital converter and accepts coefficients. A secondary impulse shortening filter receives the output signal of the analog to digital converter, outputs an output signal, and passes coefficients to the primary impulse shortening filter. A reference signal generator outputs a reference signal. A comparator compares the output signal and the reference signal and outputs a resulting error signal. An adaptive processor computes coefficients for the secondary impulse shortening filter based on the error signal. | 12-01-2011 |
| 20110305306 | BLIND ADAPTIVE FILTER FOR NARROWBAND INTERFERENCE CANCELLATION - The present invention relates to a blind adaptive filter for narrowband interference cancellation, which includes an adaptive filter, a delay unit coupled to the adaptive filter for generating a delayed signal with a predetermined delay length from the output signal of the adaptive filter, and an error calculation unit coupled to the adaptive filter and the delay unit. The error calculation unit compares the output signal from the adaptive filter and the delayed signal from the delay unit to extract error information, and feedback the first error information to the adaptive filter. The first error information is formed of a transfer function including a number of coefficients, and used to adjust the adaptive filter and remove interference in the next input signal. The disclosed technique is also applicable in wideband receivers, as well as resisting multiple strong narrowband interferences having a frequency sweep rate of tens of milliseconds. | 12-15-2011 |
| 20110311007 | Method and an Apparatus for Forming Signal Estimates - The invention relates to a method and a device for extracting the signal components and/or the interference components. In the invention a channel measurement signal is received, the signal is filtered, the filtered signal is reconstructed, the reconstructed signal is subtracted from the channel measurement signal for obtaining a residual signal (r-s); and the residual signal is fed back to be combined with the channel measurement signal. | 12-22-2011 |
| 20120002770 | SECOND-ORDER DISTORTION CORRECTING RECEIVER AND SECOND-ORDER DISTORTION CORRECTING METHOD - A second-order distortion correcting receiver and a second-order distortion correcting method, wherein second-order inter-modulation distortion can be cancelled with high precision and with a simple circuit configuration, without requiring a complicated adjustment step. A non-linear active element unit ( | 01-05-2012 |
| 20120014486 | PRECISION METHOD FOR ALIGNING RADIO FREQUENCY PULSE TIMING CHARACTERISTICS - A system and method for correlating first pulsed signals with second pulsed signals includes a first receiving unit, a second receiving unit and a correlation device. The first receiving unit is disposed to receive from a first device one or more first pulsed signals. The first device may include a plurality of pulsed radio frequency source under test signal sources. The second receiving unit is disposed to receive from a second device one or more second pulsed signals. The second device may include a local oscillator pulsed signal source. The correlation device can correlate the first pulsed signals with the second pulsed signals to align a timing characteristic of the first pulsed signals to the equivalent timing characteristic of the second pulsed signals. | 01-19-2012 |
| 20120014487 | Adaptive Narrowband Interference Prediction Circuit and Method - An input signal that includes narrowband interference is spectrally enhanced by an adaptive circuit that supplies as output signal(s), portion(s) of NBI at one or more frequencies that change adaptively. The output signal(s) are used in one or more tone predictor(s) to generate, based on prior values of the NBI portion, one or more predicted tone signals that are subtracted from a received signal containing the NBI, and the result is used in the normal manner, e.g. decoded. The adaptive circuit and the one or more tone predictor(s), form a feed-forward NBI predictor wherein the received signal is supplied as the input signal of the adaptive circuit. The result of subtraction may be supplied to a slicer that slices the result, yielding a sliced signal which is subtracted from the received signal to generate a signal can be used as the input signal, to implement a feedback NBI predictor. | 01-19-2012 |
| 20120020443 | METHOD FOR PROCESSING A SIGNAL, IN PARTICULAR A DIGITAL AUDIO SIGNAL - The invention relates to a method for processing a signal, in particular a digital audio signal, suitable for being implemented by a digital signal processor (DSP) having libraries for calculating Fourier transforms from the complex number space to the complex number space, for digitally processing P input signals, P being an integer at least equal to 2, more particularly for filtering said P input signals by the convolution of sampled fast Fourier transforms (FFT), thus obtaining Q output signals, Q being an integer at least equal to 2. According to the invention, the method includes at least the following steps: grouping said P input signals by twos, one representing the real portion and the other the imaginary portion of a complex number, thus defining one or more input vectors, filtering said input vector or vectors, passing through the Fourier space, thus generating one or more output vectors, which are complex numbers, the real portion and the imaginary portion of said vector or each one of said output vectors respectively representing one of said Q output signals. | 01-26-2012 |
| 20120027140 | SYSTEM AND METHOD FOR CHANNEL ESTIMATION - A method for channel estimation includes receiving data at a number of frequency intervals in a frequency band over a number of first time intervals. A first set of channel estimates is determined for each pilot symbol within the data over a second time interval comprising at least one first time interval, and time-direction interpolation is performed to determine a second set of channel estimates for a number of data portions in a frequency interval using the first set of channel estimates. The frequency interval comprises a data portion comprising a pilot symbol. Frequency-direction interpolation is performed to determine a third set of channel estimates for each first time interval. The time-direction interpolation and the frequency-direction interpolation can be performed in reverse order with the channel estimates generated by the frequency-direction interpolation being used as inputs for time-direction interpolation. | 02-02-2012 |
| 20120027141 | Method and Apparatus for Cross Polarization and Cross Satellite Interference Cancellation - A method and apparatus in which a Tap-Weight Computer (TWC) calculates a Tap-Weight Vector (TWV). The TWV is coupled to a register in each of a plurality of adaptive filter modules. Each such adaptive filter module includes several adaptive filters that each include a tapped delay line. The input to the tapped delay line of each such adaptive filter is one of a plurality of potential interfering signals. The TWV controls the weighting of the outputs from the taps off the delay line. The weighted outputs from each tapped delay line are then subtracted from a received signal which potentially includes interference from the potential interfering signals. The TWC is multiplexed to each of the plurality of adaptive filters so that each adaptive filter is loaded with a TWV calculated by the TWC to reduce the amount of interference contributed by a particular potential interfering signal coupled to an input to that particular adaptive filter. In one embodiment, a plurality of such adaptive filter modules share the same TWC. | 02-02-2012 |
| 20120027142 | DEVICE AND METHOD FOR REDUCING INTERFERENCE IN RECEIVED COMMUNICATION SIGNALS | 02-02-2012 |
| 20120033769 | MULTIMODE RECEIVER WITH A TRANSLATIONAL LOOP FOR INPUT MATCHING - A multimode receiver has a transconductance amplifier having an input terminal and adapted to receive a voltage RF signal and to deliver a current RF signal. The amplifier has a current mixer coupled to the transconductance amplifier and adapted to receive the current RF signal, the current mixer being adapted to combine the current RF signal with a signal generated by a local oscillator, the mixer generating an intermediate frequency signal having a frequency that equals a combination of a frequency of the current RF signal and a frequency of the local oscillator. A low-pass filter is coupled to the mixer and is adapted to generate a low-pass current signal. A transimpedance amplifier is coupled to the low-pass filter and is adapted to receive the low-pass current signal, the transimpedance amplifier being adapted to generate an intermediate frequency voltage signal proportional with the low-pass current signal. A first switch is adapted to receive a signal proportional with the intermediate frequency voltage signal at a first end, a second end being coupled to the input terminal and a second switch is coupled between the input terminal and a reference terminal. The first and second switches are mutually exclusive in an ON state in a specific mode of operation of the multimode receiver. | 02-09-2012 |
| 20120033770 | METHOD AND APPARATUS FOR ADJUSTING CHANNEL DELAY PARAMETER OF MULTI-CHANNEL SIGNAL - A method and an apparatus for adjusting a channel delay parameter of a multi-channel signal are provided in the embodiments of the present invention. The method includes: performing down-mixing processing on a multi-channel signal to obtain a processed signal ( | 02-09-2012 |
| 20120045027 | NOISE REDUCTION IN WIRELESS COMMUNICATION APPLICATIONS - A noise reduction system in a wireless communication network, including: two or more input antennas adapted to receive wireless signals; wherein each input antenna has a different receiving characteristic, so that the signals provided by the input antennas constitute a distinct combination of the received signals; a filter coupled to each of the input antennas except one, wherein the filter is adapted to estimate the correlation between the signal provided by its associated input antenna and the signal provided by the input antenna not coupled to a filter and mitigate a dominant component of the received signals responsive to the estimation; a summator that is adapted to combine the filtered signal and the signal provided by the input antenna not coupled to a filter and provide the result as feedback to the filter; and wherein the filtered signals from all the filters are combined to form an output signal. | 02-23-2012 |
| 20120063554 | OVERSAMPLED SYNTHESIZER SYSTEMS AND METHODS - Systems and methods for combining digital input signals in an oversampled synthesizer system are provided. An inverse Fourier transform component is configured to receive a plurality of digital input signals, having a first sampled rate, and produce a corresponding representation of a wideband signal as a plurality of parallel outputs. A plurality of digital filters are each configured to apply a transfer function to an associated one of the parallel outputs to produce a filtered output. A number of filters in the plurality of digital filters is less than a number of parallel outputs of the inverse Fourier transform component, such that at least one of the parallel outputs is not provided to any filter of the plurality of digital filters. An interpolation component combines the plurality of filtered outputs into a wideband digital output signal having a second sampled rate. | 03-15-2012 |
| 20120063555 | SAW-LESS, LNA-LESS LOW NOISE RECEIVER - A low noise receiver includes a downconverter configured to receive a radio frequency (RF) signal, the downconverter comprising a switching architecture configured to generate a plurality of output phases based on a respective plurality of local oscillator (LO) signals, a differencing circuit configured to combine the plurality of output phases such that an nth output phase is differenced with an (n+K)th output phase, resulting in gain-added output phases, and a summation filter configured to receive the gain-added output phases and configured to combine the gain-added output phases such that a response of the receiver effectively reduces odd harmonics of the RF signal. | 03-15-2012 |
| 20120076250 | METHOD FOR PEAK TO AVERAGE POWER RATIO REDUCTION - According to various embodiments, methods, apparatuses and systems are provided to allow a transmitter to reduce the Peak to Average Power Ratio (PAPR) of a modulated signal by applying a pre-emphasis filter to the signal, clipping the pre-distorted signal to reduce the PAPR, and applying a de-emphasis filter to the clipped signal to reduce the spectral leakage caused by the clipping. Other embodiments may be disclosed or claimed. | 03-29-2012 |
| 20120082277 | CONFIGURABLE ADAPTIVE FILTER - Method and apparatuses are disclosed to substantially compensate for various unwanted interferences and/or distortions within a communications receiver. Each of these apparatuses and methods estimate the various unwanted interferences and/or distortions within the communications receiver. Each of these apparatuses and methods remove the estimates of the various unwanted interferences and/or distortions within the communications receiver from one or more communications signals within the communications receiver to substantially compensate for the various unwanted interferences and/or distortions. | 04-05-2012 |
| 20120082278 | COMPENSATING FOR UNWANTED INTERFERENCE IN A COMMUNICATIONS RECEIVER - Method and apparatuses are disclosed to substantially compensate for various unwanted interferences and/or distortions within a communications receiver. Each of these apparatuses and methods estimate the various unwanted interferences and/or distortions within the communications receiver. Each of these apparatuses and methods remove the estimates of the various unwanted interferences and/or distortions within the communications receiver from one or more communications signals within the communications receiver to substantially compensate for the various unwanted interferences and/or distortions. | 04-05-2012 |
| 20120087451 | Digital Correction of Analog Polyphase Filters - Embodiments of the present invention provide systems, devices and methods for modeling and correcting amplitude and quadrature phase errors generated within analog components of a receiver. A frequency-dependent correction method is employed that closely tracks the frequency dependent nature of the mismatch between the I and Q polyphase filter responses. In particular, digital correction is performed on a signal based on a modeled error function generated during a calibration of the receiver | 04-12-2012 |
| 20120099685 | Broadband Tuner for Very Wide Signal Conversion - An agile RF tuner circuit capable of converting a wide portion of RF signal into an IF signal suitable for analog-to-digital conversion. The circuit up converts a received RF signal to a high IF signal and then down converts the high IF signal to a low IF signal. Embodiments of the RF circuit incorporate harmonic reject mixers to suppress harmonics and intermodulations typically associated with the frequency conversion process. | 04-26-2012 |
| 20120099686 | Broadband Tuner for Very Wide Signal Conversion - An agile RF tuner circuit capable of converting a wide portion of RF signal into an IF signal suitable for analog-to-digital conversion. The circuit up converts a received RF signal to a high IF signal and then down converts the high IF signal to a low IF signal. Embodiments of the RF circuit incorporate harmonic reject mixers to suppress harmonics and intermodulations typically associated with the frequency conversion process. | 04-26-2012 |
| 20120140860 | NON-LINEAR ADAPTIVE SCHEME FOR CANCELLATION OF TRANSMIT OUT OF BAND EMISSIONS - A method and apparatus for a non-linear adaptive scheme for transmit out of band emission cancellation is provided. Embodiments disclosed herein provide a method for removing unwanted transmitter emissions from a composite received signal. The method performs the steps of: extracting the I and Q samples from a modulator output; inputting the I and Q samples to a non-linear filter; applying weights to the non-linear filter outputs, combining the non-linear filter outputs to generate a broadband emission estimate; selecting a portion of a transmit emission in a desired portion of a receive band; subtracting an output of the non-linear filter from a composite signal; and feeding back a residual error to the non-linear filter; adapting the non-linear filter iteratively. | 06-07-2012 |
| 20120155583 | RADIO COMMUNICATION DEVICE HAVING CARRIER PHASE NOISE ELIMINATION FUNCTION, AND RADIO COMMUNICATION METHOD - A radio communication device reproduces a carrier signal by eliminating phase noise from a carrier phase signal detected from a received baseband signal. Herein, a filtering characteristic having a default value is adopted to eliminate phase noise from the carrier phase signal with respect to a firstly received baseband signal. Integrated phase noise characteristics are calculated by adding a transmission-side phase noise characteristic, which is extracted from a radio frame demodulated from the carrier signal, to a predetermined reception-side phase noise characteristic. An optimum filtering characteristic is selected through comparison between a threshold and integrated phase noise characteristics. The selected filtering characteristic is adopted to eliminate a noise component from the carrier phase signal with respect to a subsequent baseband signal. | 06-21-2012 |
| 20120163517 | SIGNAL RECEIVER WITH DIGITAL FRONT END SUPPORTING MULTIPLE BAND AND SIGNAL RECEIVING METHOD USING THE SAME - Disclosed is a method for receiving an analog signal from a receiver supporting at least a first channel band and a second channel band. The method for receiving an analog signal includes sampling the analog signal received through an antenna, generating a decimated signal by passing the sampled signal to a CIC decimation filter; and inputting the decimated signal to a channel selection filter. | 06-28-2012 |
| 20120163518 | Method and Apparatus for Broadband Data Conversion - A receiver may receive a signal and process each of a plurality of sub-bands of the received signal via a respective one of a plurality of first-type receive chains. The receiver may utilize a signal output by a first one of the plurality of the first-type receive chains to remove undesired signals from a signal output by a second one of the plurality of the first-type receive chains. The undesired signals may comprise aliases and/or harmonics of one or more signals that fall within a sub-band of the first one of the plurality of the first-type receive chains. The receiver may downconvert, filter, and digitize each of the plurality of sub-bands via a corresponding one of the plurality of the first type receive chains. The received signal may encompass the cable television band, and each of the plurality of sub-bands may comprise a plurality of cable television channels. | 06-28-2012 |
| 20120183109 | WORLD DIGITAL RADIO RECEIVER WITH IMAGE SIGNAL REJECTION - A broadcast receiver with image rejection is proposed. The broadcast receiver includes a radio frequency processing unit and a baseband processing unit. The radio frequency processing unit receives a first input signal and a second input signal, amplifies the first input signal and the second input signal, down-converts the second input signal, and generating a first signal and a down-converted second signal. Besides, the baseband processing unit receives one of the first signal and the down-converted second signal, filters the received signal thereof, wherein the baseband processing unit comprises an anti-aliasing filter unit which attenuates adjacent channel interference of the received signal, and when the received signal is the down-converted second signal, the anti-aliasing filter unit attenuates a portion of an image signal in the received signal. | 07-19-2012 |
| 20120183110 | Distortion and aliasing reduction for digital to analog conversion - Distortion and aliasing reduction for digital to analog conversion. Synthesis of one or more distortion terms made based on a digital signal (e.g., one or more digital codewords) is performed in accordance with digital to analog conversion. The one or more distortion terms may correspond to aliased higher-order harmonics, distortion, nonlinearities, clipping, etc. Such distortion terms may be known a priori, such as based upon particular characteristics of a given device, operational history, etc. Alternatively, such distortion terms may be determined based upon operation of a device and/or based upon an analog signal generated from the analog to conversion process. For example, frequency selective measurements made based on an analog signal generated from the digital to analog conversion may be used for determination of and/or adaptation of the one or more distortion terms. One or more DACs may be employed within various architectures operative to perform digital to analog conversion. | 07-19-2012 |
| 20120213317 | Receiver for Compensating I/Q Mismatch, Compensation Device, Compensation Module and Compensation Parameter Calculating Module - A receiver for compensating I/Q mismatch includes an analog down-conversion unit for receiving a radio frequency signal and down-converting the RF signal into a set of digital low intermediate frequency (IF) signals, a digital down-conversion unit receiving the set of digital low IF signals and down-converting the set of digital low IF signals into first and second baseband signals, and a compensation unit. The compensation unit receives the first and second baseband signals, calculates a compensation parameter based thereon, and compensates I/Q mismatch effect according to the first and second baseband signals and the compensation parameter so as to output a target signal. | 08-23-2012 |
| 20120236976 | RADIO RECEIVER - Various apparatuses and methods are described to reduce interference in signals subject to intermodulation products and high power narrow band interfering signals on lower power wideband signals. Apparatuses and methods described herein also provide the capability for supporting multi-standards, multi-modes and multi-bands in wireless and wired applications with a single receiver or a receiver with minor variations. The receiver described herein samples the entire band in which there can be signals of interest or signals that can generate interference. All of these signals are sampled in one bit stream and the bit stream is processed to isolate signals of interest and interfering signals. The isolated interfering signals are then cancelled out of the signals of interest. | 09-20-2012 |
| 20120250810 | DEVICE AND METHOD FOR RECEIVING RF SIGNALS BASED ON HETERODYNE ARCHITECTURE USING COMPLEX IF SUBSAMPLING - An RF signal reception device including: a transposition device of signals of frequency f | 10-04-2012 |
| 20120269307 | PROCESSING A RADIO FREQUENCY SIGNAL - Circuitry and a method for use in a radio frequency receiver for processing a radio frequency signal are provided. The circuitry comprises a mixer arranged to receive the radio frequency signal and down-convert the received radio frequency signal to a lower frequency. The received radio frequency signal has an interference component and the interference component in the down-converted signal is within an interference frequency range. The circuitry also comprises an LC based notch filter arranged to receive the down-converted signal from the mixer, filter the down-converted signal, and output the filtered signal for processing by a baseband processing block. The LC based notch filter has a notch centered within said interference frequency range, such that the LC based notch filter is arranged to attenuate the interference component in the down-converted signal. | 10-25-2012 |
| 20120288044 | PHASE / FREQUENCY SYNTHESIS USING PERIODIC SIGMA-DELTA MODULATED BIT-STREAM TECHNIQUES - A method and a circuit are provided for providing phase or frequency synthesis using sigma-delta modulation bit-stream techniques in which data is encoded utilizing sigma-delta modulation and then digital-to-time conversion (DTC) or digital-to-frequency conversion (DFC). In some embodiments this encoded data stream is further subjected to phase or frequency domain filtering, which in some embodiments is carried out by a higher-order phase-locked loop (PLL). | 11-15-2012 |
| 20120288045 | SIGNAL RECEIVING APPARATUS AND METHOD OF CONTROLLING FILTERS IN SIGNAL RECEIVING APPARATUS - A signal receiving device receives an incoming signal to obtain a frequency signal. The signal receiving device has a multi-filter device. The frequency signal is subjected to frequency selection processing by using the multi-filter device. The multi-filter device has a plurality of filters whose frequency characteristics are different from each other. The filters are connected in series. If the received signal intensity is higher than prescribed threshold intensity, the center frequency of at least one of the filters in the multi-filter device is biased. | 11-15-2012 |
| 20120307948 | METHOD TO CANCEL IMPULSIVE INTERFERENCE FROM A SIGNAL PROCESSING SYSTEM - A method of canceling impulsive interference from a communications signal is provided. The method includes identifying an impulse interference contained in the communications signal, generating a model of impulse interference, matching the model in at least one of amplitude, phase and envelope time delay to the identified impulse interference, and cancelling the identified impulse interference by subtracting the matched model from the identified impulse interference. | 12-06-2012 |
| 20120314824 | INTERFERENCE WAVE SUPPRESSING APPARATUS, RELAY APPARATUS, RELAY SYSTEM, AND INTERFERENCE WAVE SUPPRESSING METHOD - An interference wave suppressing apparatus includes a digital demultiplexing unit configured to demultiplex a reception signal into demultiplexed signals having predetermined bandwidth, an interference-wave detecting unit configured to determine, for each of the demultiplexed signals, based on a power value, whether an interference wave is present, an interference-wave suppressing unit configured to change a signal value of the demultiplexed signal, in which the interference-wave detecting unit determines that an interference wave is present, to a value equal to or smaller than a predetermined value, output the demultiplexed signal, and output the demultiplexed signal, in which the interference-wave detecting unit determines that an interference wave is absent, and a digital multiplexing unit configured to multiplex the signals output from the interference-wave suppressing unit. | 12-13-2012 |
| 20130003904 | DELAY ESTIMATION BASED ON REDUCED DATA SETS - A delay estimation unit is disclosed. The delay estimation unit may receive first and second streams of data having identical content. The amount of data in the data streams is reduced by filtering (e.g., lowpass filtering) the first and second data streams to produce first and second filtered streams, respectively. The amount of data is further reduced by decimating the first and second filtered streams, discarding all but one of every N samples to produce first and second decimated data, respectively. The first and second decimated streams are received by a correlator that performs a correlation operation. The output of the correlator is received by a peak search unit that analyzes the correlation results over time and searches for peaks that indicate alignment of the first and second data streams. | 01-03-2013 |
| 20130028357 | DETECTION AND MITIGATION OF INTERFERENCE IN A RECEIVER - A novel receiver architecture optimizes receiver performance in the presence of interference. In various embodiments, power estimation circuits are used with variable selectivity to determine the exact nature of the interference and to optimize the performance correspondingly. The variable selectivity is achieved using stages of filtering with progressively narrower bandwidths. Also, the actual method of optimizing the receiver performance is novel compared to the prior art in that the gain settings and the baseband filter order (stages to be used) will be optimized based on the nature of the interference as determined by the power detector measurements. For a device such as a cellular phone that operates in a dynamic and changing environment where interference is variable, embodiments advantageously provide the capability to modify the receiver's operational state depending on the interference. | 01-31-2013 |
| 20130028358 | Narrowband Interference Detector - The present invention discloses a narrow band interference detector for a receiver of a communication system. The narrow band interference detector includes a numerically-controlled oscillator (NCO), for generating an oscillating signal according to a time-variable frequency; a mixer, for mixing an input signal with the oscillating signal, to generate a mixed signal; a phase lock loop (PLL), for locking the mixed signal during a detection period according to the time-variable frequency; a first switch, for controlling a connection between the NCO and the PLL according to a desirable narrow band interference signal type of the at least one narrow band interference signal; and a narrow band determination unit, for determining at least one narrow band interference signal according to a low frequency component of the mixed signal, the time-variable frequency and the desirable narrow band interference signal type of the at least one narrow band interference signal. | 01-31-2013 |
| 20130028359 | PROGRAMMABLE DISCRETE DIGITAL RECEIVER COMPONENTS - A receiver includes a sample and hold module, a discrete time filter module, and a conversion module. The sample and hold module includes a sample switching module, an impedance module, and a hold switching module. The sample switching module outputs samples of an inbound wireless signal in accordance with a sampling clock signal. The impedance module temporarily stores the samples. The hold switching module outputs a filtered representation of the samples in accordance with a hold clock signal to produce a frequency domain sample pulse train, wherein a filter response of the sample and hold module is in accordance with a ratio between the sampling clock signal and the hold clock signal. The discrete time filter module, which may be programmable, filters the frequency domain sample pulse train. The conversion module, which may be programmable, converts the filtered sample pulse into an inbound baseband signal. | 01-31-2013 |
| 20130028360 | WIDE BANDWIDTH DISCRETE DIGITAL RECEIVER - A receiver includes a sample and hold module, a discrete time filter module, and a wireless frequency to baseband conversion module. The sample and hold module is operable to sample and hold an inbound wireless signal at a rate corresponding to a multiple of a carrier frequency of the inbound wireless signal to produce a frequency domain sample pulse train. The discrete time filter module is operable to filter the frequency domain sample pulse train to produce a wireless frequency pulse. The wireless frequency to baseband conversion module is operable to convert the wireless frequency pulse to a baseband digital signal. | 01-31-2013 |
| 20130028361 | DISCRETE DIGITAL RECEIVER WITH BLOCKER CIRCUIT - A receiver includes a bandpass filter module, a sample and hold module, a discrete time bandpass filter module, a discrete time notch filter module, a combining module, and a conversion module. The bandpass filter module filters an inbound wireless that includes a desired signal component and an undesired signal component. The sample and hold module is operable to sample and hold the filtered inbound wireless signal to produce a frequency domain sample pulse train. The discrete time bandpass filter module bandpass filters the frequency domain sample pulse train to produce a bandpass filtered sample pulse. The discrete time notch filter module notch filters the frequency domain sample pulse train to produce a notched filtered sample pulse. The combining module combines the bandpass filtered sample pulse and the notched filtered sample pulse to produce a filtered inbound signal. The conversion module converts the filtered inbound signal into an inbound baseband signal. | 01-31-2013 |
| 20130028362 | MULTIPLE PATH DISCRETE DIGITAL RECEIVER - A receiver includes a bandpass filter module, a sample and hold module, first and second discrete time filter modules, and first and second conversion modules. The bandpass filter module is operable to filter an inbound wireless signal. The sample and hold module is operable to sample and hold the filtered inbound wireless signal to produce a frequency domain sample pulse train. The first discrete time filter module is operable to filter the frequency domain sample pulse train to produce a first filtered sample pulse. The second discrete time filter module is operable to filter the frequency domain sample pulse train to produce a second filtered sample pulse. The first conversion module is operable to convert the first filtered sample pulse into a first inbound baseband signal. The second conversion module is operable to convert the second filtered sample pulse into a second inbound baseband signal. | 01-31-2013 |
| 20130028363 | MULTIPLE INPUT DISCRETE DIGITAL RECEIVER - A receiver includes a sample and hold module, a discrete time filter module, and a conversion module. The sample and hold module is operable to sample and hold a first inbound wireless signal and a second inbound wireless signal to produce a frequency domain sample pulse train. The discrete time filter module is operable to filter the frequency domain sample pulse train to produce a first filtered sample pulse corresponding to the first inbound wireless signal and to produce a second filtered sample pulse corresponding to the second inbound wireless signal. The conversion module is operable to convert the first filtered sample pulse into a first inbound baseband signal and to convert the second filtered sample pulse into a second inbound baseband signal. | 01-31-2013 |
| 20130034196 | Systems and Methods for Cancelling Cross Polarization Interference in Wireless Communication Using Polarization Diversity - An exemplary system may comprise a first and second device and a first and second power splitter coupled to a single cable. The first device may be configured to receive a first noise signal of a first polarization, and to adaptively cancel, based on the first noise signal, first noise from the noisy signal associated with an orthogonal polarization. The second device may be configured to receive a second noise signal of a second polarization, and to adaptively cancel second noise from the noisy signal associated with an orthogonal polarization based on the second noise signal. The first power splitter may be configured to receive the first noise signal from the single cable and provide the first noise signal to the first device. The second power splitter may be configured to receive the second noise signal from the single cable and provide the second noise signal to the second device. | 02-07-2013 |
| 20130058443 | Method of Doppler Spread Estimation - A method includes receiving a signal comprising a symbol-carrier matrix, the symbol-carrier matrix including a predetermined pattern of reference symbols, and determining at least one channel estimate Ĥ | 03-07-2013 |
| 20130070878 | RECEIVER APPARATUS HAVING FILTERS IMPLEMENTED USING FREQUENCY TRANSLATION TECHNIQUES - A method and apparatus is disclosed to effectively frequency translate a filter characterized as a low quality factor (Q) filter, corresponding to a baseband frequency of approximately zero Hertz or to an intermediate frequency (IF), to a filter characterized as a high Q filter at frequencies greater than the baseband frequency or the IF. A downconversion mixer frequency translates a communication signal to the baseband frequency or the IF using a first local oscillator signal to provide a downconverted communication signal. A filter corresponding to the baseband frequency or the IF filters the downconverted communication signal to provide a filtered communication signal. An upconversion mixer frequency translates a communication signal using a second local oscillator signal. The frequency translation by the upconversion mixer, in effect, translates the filter characterization from the low Q filter to the high Q filter at frequencies greater than the baseband frequency or the IF. | 03-21-2013 |
| 20130083876 | BASE STATION AND RECEIVING METHOD - A base station includes antennas, a local signal generator; first and second mixers generating first and second mixed signals by mixing first and second signals from first and second antenna among the antennas and the local signal; first and second analog digital converters converting to first and second digital signals, first and second interference detecting units detecting first and second interference signals based on the first and second digital signals; first and second interference removing units generating first and second processed signals by removing the first and second interference signals by first and second filters having first and second filter central frequencies shifted in first and second directions from first and second interference central frequencies of the first and second interference signals, respectively; and a combining unit combining the first and second processed signals. | 04-04-2013 |
| 20130089169 | Low-Power and Low-Cost Adaptive Self-Linearization System with Fast Convergence - A signal processing method includes inputting a digital signal, providing a plurality of coefficients; and determining an output. The output is approximately equal to an aggregate of a plurality of linear reference components, and each of the linear reference components is approximately equal to an aggregate of a corresponding set of digital signal samples that is scaled by the plurality of coefficients. | 04-11-2013 |
| 20130101074 | PROGRAMMABLE, FREQUENCY AGILE DIRECT CONVERSION DIGITAL RECEIVER WITH HIGH SPEED OVERSAMPLING - The invention described herein is directed to different embodiments of a wireless communications device that can be used in many different applications, such as but not limited to a digital oversampling receiver adapted to select desired signals and to reject undesired signals. In one embodiment, a wireless communications device is disclosed that comprises an architecture for a receiver front end that obviates the need for high order passive circuitry or RC active circuitry to select desired signals and to reject undesired signals. | 04-25-2013 |
| 20130114770 | METHOD FOR REDUCING CHANNEL LENGTH AND CORRESPONDING FILTER AND SIGNAL - A method and apparatus are provided for reducing a channel length. The method implements a channel-length reduction filter that takes into account a pulse response of the channel. The method includes the following steps: cutting the filter into at least one first and one second portion; optimizing said first portion of the filter according to a first criterion in order to output a first set of filtering coefficients; reducing the length of the channel by optimizing said second portion of the filter according to a second criterion different from the first one and based on the first set of filtering coefficients of said first portion of the filter in order to output a second set of filtering coefficients. | 05-09-2013 |
| 20130129024 | Methods of Receiving and Receivers - A receiver uses a local oscillator to receive data transmitted via a combination of radio frequency signals using carrier aggregation. Each radio frequency signal occupies a respective radio frequency band and the radio frequency bands are arranged in two groups, a first group and a second group, separated in frequency by a first frequency region, each of the groups including one or more radio frequency bands and the first group occupying a wider frequency region than the second group. The radio frequency signals are processed using the local oscillator by setting the local oscillator, during the processing, to a frequency that is offset from the centre of a band defined by outer edges of the frequency regions occupied by the two groups. | 05-23-2013 |
| 20130142295 | RF (INCLUDING GNSS) SIGNAL INTERFERENCE MITIGATION SYSTEM AND METHOD - An RF (e.g., GNSS) interference mitigation system and method uses a switchable bank of filters for selectively blocking signals in predetermined bandwidths based on detecting strong, interfering signals with an interference detection circuit including a sniffer antenna. A low-strength RF (e.g., GNSS) system can be combined with a spectrally-close high-strength, telecommunications receiver system for cooperative control. Alternatively, an RF receiver can detect tones, changes in DC bias or level changes to activate a filter selection switch. | 06-06-2013 |
| 20130202071 | LNB FREQUENCY DOWN CONVERSION INTEGRATED CIRCUIT AND CHIP, LNB FREQUENCY DOWN CONVERSION CIRCUIT AND METHOD - The present invention discloses a type of LNB frequency down conversion integrated circuit. The present invention frequency-down-converts the RF signal with the Quadrature local oscillation signal (LO) and Quadrature Mixer. Then the 90 degree phase-shifting of the quadrature intermediate frequency (IF) signal after mixed is done by the use of passive Polyphase filter. The present invention further discloses a LNB frequency down conversion chip, a LNB frequency down circuit adopting the LNB frequency down conversion chip circuit and a method of LBN frequency down. The invention ensures the elimination of the minor image signal and the realization of the minor image suppression function. | 08-08-2013 |
| 20130208838 | DETECTION AND FILTERING OF AN UNDESIRED NARROWBAND SIGNAL CONTRIBUTION IN A WIRELESS SIGNAL RECEIVER - Techniques are provided which may be implemented using various methods and/or apparatuses in a device comprising a receiver to scan a spectral band of a received signal comprising a desired signal contribution to determine whether signal data associated with at least a sub-band of the spectral band further comprises at least one undesired signal contribution. In response to determining that the signal data comprises at least one undesired signal contribution, the mobile station may initiate at least one notch filter to affect the undesired signal contribution in subsequent signal data associated with the received signal. | 08-15-2013 |
| 20130230131 | Wideband Receiver - A receiver and method for identifying the frequency of an RF component in an RF signal are disclosed. The receiver includes a first mixer that receives an RF signal and mixes that RF signal with a first multi-tone LO signal that includes a plurality of tones to generate a mixed signal. The output of the first mixer is filtered by a first filter that removes signals outside of a predetermined band to generate a first IF signal. A processor determines the RF frequency of the component utilizing the first IF signal and a second IF signal generated using a second multi-tone LO signal having a different plurality of tones from said first multi-tone signal. The first and second multi-tone LO signals can be generated by clocking suitable digital sequences into the mixer either by using different sequences or by using the same sequence clocked at a different rate. | 09-05-2013 |
| 20130235961 | APPARATUS AND METHOD FOR REDUCING RX CALIBRATION DELAY IN WIRELESS COMMUNICATION SYSTEM - An apparatus and a method for removing RX DC in a wireless communication system are provided. A receiver apparatus includes a local oscillator, a mixer for converting a received signal to a baseband signal using a frequency provided from the local oscillator, and a DC compensator, comprising an operational amplifier and a low pass filter, for compensating DC in an output signal of a frequency converter by adjusting a pass band size of the low pass filter. | 09-12-2013 |
| 20130243135 | Correction of Quadrature Errors - Correction of quadrature errors associated with digital communications systems. A correction network may correct a difference between a transmission characteristic of an in-phase signal path and a transmission characteristic of a quadrature signal path. The quadrature signal path may be for the transmission of in-phase and quadrature parts of a signal and the signal comprising frequency components within a baseband. The correction network may include an in-phase input port, a quadrature input port, an in-phase output port and a quadrature output port. Each input port may be connected to each output port by a digital filter network, which may include a set of filter tap coefficients and configuration means for configuring values of the coefficients. Frequency dependent quadrature impairments, e.g., due to the analogue components of a quadrature up-converter or down-converter, may be corrected by suitable control of the coefficients. | 09-19-2013 |
| 20130251081 | ADJACENT-CHANNEL INTERFERENCE REJECT FILTER DEVICE, WIRELESS COMMUNICATION DEVICE, AND KEYLESS ENTRY DEVICE - According to one embodiment, an adjacent-channel interference reject filter comprises a short-pulse inverter which includes a short-pulse sensor configured to detect a pulse in an intermediate frequency signal supplied to the device. The short-pulse sensor detects pulses having a pulse width less than or equal to some predetermined width. The short-pulse inverter also includes a pulse inverter configured to invert the pulse detected by the short-pulse sensor. The adjacent-channel interference reject filter may also include an inversion controller to control the inverting of detected short pulses. An adjacent-channel interference reject filter may be included in various devices such as wireless communication devices. | 09-26-2013 |
| 20130251082 | DIGITAL RECEIVER AND WAVEFORM COMPENSATION METHOD - An objective is to provide a digital receiver and a method of compensating waveform that are capable of compensating waveform distortion without increasing the circuit size. A digital receiver | 09-26-2013 |
| 20130266101 | Sampling Receiver with Inherent Mixer Functionality - One embodiment of the present invention relates to a combined mixer filter circuit. The circuit includes a sampler, a plurality of filter branches, and a coefficient generator. The sampler is configured to provide a sampled signal by sampling a received signal at a specified rate. The plurality of filter branches has selectable filter coefficients. The plurality of filter branches are configured to receive the sampled signal and generate a mixed and filtered output signal without a separate mixer component. The coefficient generator is coupled to the plurality of filter branches. The coefficient generator is configured to assign filter coefficient values to the selectable filter coefficients to yield a selected mixing function for the mixed filtered output signal. | 10-10-2013 |
| 20130266102 | RF RECEIVER AND DIGITALLY-ASSISTED CALIBRATION METHOD APPLICABLE THERETO - A radio frequency (RF) receiver includes a digital tuning engine; I-path and Q-path analog filters, tuned by the digital tuning engine; and a digital compensation circuit. The digital tuning engine executes a RC (resistor-capacitor) time constant calibration to adjust respective cut-off frequencies of the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter mismatch calibration to match the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter residual mismatch calibration to match an I-path response from the I-path analog filter to the digital compensation circuit and a Q-path response from the Q-path analog filter to the digital compensation circuit. | 10-10-2013 |
| 20130301766 | IMPULSE NOISE MITIGATION UNDER OUT-OF-BAND INTERFERENCE CONDITIONS - An impulse noise mitigation circuit (INMC) may set a cut-off frequency of each of two high pass filters to bound a frequency bandwidth of a desired signal, wherein a first of the two filters allows frequencies higher than the frequency bandwidth of the desired signal, and a second of the two filters allows frequencies lower than the frequency bandwidth of the desired signal. The INMC may compute and store a mean magnitude separately for a first signal response of the first filter and a second signal response of the second filter. The INMC may select the first filter for impulse noise mitigation when the mean magnitude of the second filter is greater than the mean magnitude of the first filter. The INMC may select the second filter for impulse noise mitigation when the mean magnitude of the first filter is greater than the second filter. | 11-14-2013 |
| 20130315357 | METHOD AND SYSTEM FOR INTERFERENCE CANCELLATION - Aspects of a method and system for interference cancellation substantially as shown in and/or described in connection with at least one of the figures, as set forth more completely in the claims. In this regard, a receiver may be operable to receive a differential signal via a differential channel, and to sense a common mode signal on the differential channel. A frequency range in which interference is present in the common mode signal may be determined. The differential signal and the common mode signal may be filtered to attenuate frequencies outside the determined frequency range. A phase and/or amplitude of the filtered common mode signal may be adjusted based on the filtered differential signal and the adjusted and filtered common mode signal may be subtracted from the received differential signal. The common mode signal may be sensed via a pair of resistors coupled to the differential channel. | 11-28-2013 |
| 20130322586 | APPARATUS AND METHODS FOR ADAPTIVELY RESUMING RADIO CHANNEL ESTIMATION - Methods and apparatus for resuming radio channel measurements and estimations after an interruption in reception. In one exemplary embodiment of the present disclosure, an adaptive solution is provided for channel estimation based at least in part on the reception interruption duration. In one variant, an LTE UE determines a windowing length and/or “shape” for a time domain channel estimation algorithm based on at least the interruption duration. In an alternate variant, an LTE UE determines the interpolation coefficients for a filter based on the interruption duration. | 12-05-2013 |
| 20130329841 | High Frequency Signal Receiver with Self-Calibrated Group Delay Compensation - A signal receiver includes an antenna interface for receiving signals from an antenna, analog signal processing circuitry coupled to the antenna interface for processing the received signals to produce filtered signals, sampling circuitry to sample the filtered signals so as to produce digitized received signals, a digital compensator to receive the digitized received signals and compensate for non-uniform group delay introduced by the analog signal processing circuitry to produce compensated digitized received signals, and a digital processor to process the compensated digitized received signals so as to produce a result. | 12-12-2013 |
| 20130336433 | RECEIVING APPARATUS, RECEIVING METHOD, AND PROGRAM - Disclosed are a receiving apparatus, a receiving method, and a program capable of reliably obtaining predetermined information. In a case where a broadband signal where the same control information is arranged in different frequency bands is received and processed, a frequency where the control information is stably received is detected, and the control information is obtained again using the detected frequency. This frequency detection is performed by detecting a frequency capable of avoiding a no-signal band in a signal array of the broadband signal determined based on the obtained control information and the like. This technology can be applied to a receiving apparatus that receives a signal conforming to a DVB-C2 standard. | 12-19-2013 |
| 20140029707 | RECEIVER CIRCUIT AND FILTERING METHOD USED THEREIN - A receiver circuit includes a first mixer that performs frequency conversion on a first signal of containing a first frequency entered from outside to output the resulting frequency-converted first signal, and a first selector that selects one out of an output signal of the first mixer and a second signal containing a second frequency entered from outside. A filter removes a pre-set frequency band of the signal selected by the first selector, and a second selector that selects between outputting the signal removed of the frequency band to outside and outputting the signal to a subsequent side circuit. A second mixer performs frequency conversion of the signal output from the second selector to output the resulting frequency-converted signal. The second mixer is the subsequent side circuit. The second frequency has a carrier frequency of a radio signal. | 01-30-2014 |
| 20140044224 | FREQUENCY AND Q-FACTOR TUNABLE FILTERS USING FREQUENCY TRANSLATABLE IMPEDANCE STRUCTURES - A system including a filter and a downconverter. The filter is configured to receive, from a node, (i) a first signal and (ii) a second signal, and filter the second signal. The filter includes a first input impedance. The filter comprises a first plurality of switches and a first circuit. The first plurality of switches is configured to communicate with the node. The first plurality of switches is clocked at a first frequency. The first frequency is based on a frequency of the first signal. The first circuit is configured to communicate with an output of the plurality of switches. The first circuit includes a second input impedance. The second input impedance is different than the first input impedance. The downconverter is configured to (i) receive the first signal and (ii) downconvert the first signal. The filter and the downconverter are connected in parallel to the node. | 02-13-2014 |
| 20140079167 | Multi-Function Receiver With Switched Channelizer Having High Dynamic Range Active Microwave Filters Using Carbon Nanotube Electronics - Multi-function receivers are disclosed in which high dynamic range active microwave filters using nanoscale devices are disposed within a switched channelizer stage. In an embodiment the receiver includes an input low noise amplifier, a switched channelizer comprised of active filters utilizing nanoscale devices, an output amplifier, a mixer, and an analog to digital converter. Additionally, the use of highly selective active filters in the channelizer allows for the optional elimination of the mixing stage, improving cost and overall volume. | 03-20-2014 |
| 20140079168 | Method and Apparatus for Cross Polarization and Cross Satellite Interference Cancellation - A method and apparatus in which a Tap-Weight Computer (TWC) calculates a Tap-Weight Vector (TWV). The TWV is coupled to a register in each of a plurality of adaptive filter modules. Each such adaptive filter module includes several adaptive filters that each include a tapped delay line. The input to the tapped delay line of each such adaptive filter is one of a plurality of potential interfering signals. The TWV controls the weighting of the outputs from the taps off the delay line. The weighted outputs from each tapped delay line are then subtracted from a received signal which potentially includes interference from the potential interfering signals. The TWC is multiplexed to each of the plurality of adaptive filters so that each adaptive filter is loaded with a TWV calculated by the TWC to reduce the amount of interference contributed by a particular potential interfering signal coupled to an input to that particular adaptive filter. In one embodiment, a plurality of such adaptive filter modules share the same TWC. | 03-20-2014 |
| 20140086374 | SYSTEM AND METHOD FOR DETECTING BROADBAND GLOBAL POSITIONING SYSTEM (GPS) JAMMING - A system and method for detecting broadband global positioning system (GPS) jamming is provided, the system including a local oscillator maintainer to maintain a plurality of local oscillators, a frequency band selector to select a frequency band in which jamming is to be detected, in response to receipt of a radio frequency (RF) signal, an oscillating signal output unit to allow an oscillating signal to be output from a local oscillator identified based on the selected frequency band, among the plurality of local oscillators, and an intermediate frequency (IF) signal generator to generate an IF signal using the RF signal and the oscillating signal. | 03-27-2014 |
| 20140105338 | LOW-DELAY FILTERING - A method of frequency-domain filtering is provided that includes a plurality of filters, the plurality of filters including at least one constrained filter(s) | 04-17-2014 |
| 20140112423 | Method and Faculty to Measure and Compensate DCO Frequency Distortions using a DPLL - One embodiment of the present invention relates to a communication system having a digital to analog converter, a first input, a summation component, a compensation filter, and a compensation unit. The converter is configured to receive a first signal. The first input is configured to receive a phase modulation signal. The compensation filter generates a filtered frequency deviation signal to mitigate frequency distortions, such as those from a digital controlled oscillator. The compensation unit includes one or more inputs and is configured to generate a correction signal according to the filtered frequency deviation signal and the first signal. The correction signal at least partially accounts for estimated distortions of the phase modulation signal from the amplitude modulation path and mitigates frequency induced distortions. The summation component is configured to receive the phase modulation signal and the correction signal and to generate a corrected phase modulation signal as a result. | 04-24-2014 |
| 20140126675 | METHOD AND APPARATUS FOR DEMODULATION OF A DESIRED SIGNAL IN THE PRESENCE OF NONLINEAR-DISTORTED INTERFERENCE - The present disclosure provides methods and apparatuses for demodulating discrete-time desired signals in a period-T | 05-08-2014 |
| 20140140454 | Coefficient-Specific Filtering of Initial Channel Estimates - Embodiments herein include a method of channel estimation in a wireless communication node. The method comprises generating, based on samples of a received signal, initial estimates of a plurality of channel coefficients forming a channel response. The method also entails, for each of the channel coefficients, dynamically calculating a coefficient-specific filter span for that channel coefficient. Notably, the coefficient-specific filter span for any given channel coefficient is calculated according to a closed-form function that minimizes aggregated estimation noise for the channel coefficient and estimation bias attributable to errors in tracking the channel coefficient. The method finally includes adapting filtering of the initial estimates independently for each of the channel coefficients to be performed over the coefficient-specific filter span calculated for that channel coefficient. | 05-22-2014 |
| 20140140455 | SAW-LESS RECEIVER WITH RF FREQUENCY TRANSLATED BPF - A SAW-less receiver includes an interface, an RF to IF receiver section, and a receiver IF to baseband section. The RF to IF receiver section includes a frequency translated bandpass filter (FTBPF), a Low Noise Amplifier (LNA), and a mixing section. The FTBPF includes a switching network and a plurality of baseband impedances. The switching network is operable to couple the plurality of baseband impedances to the interface in accordance with a plurality of phase-offset RF clock signals to RF bandpass filter the inbound RF signal. The LNA amplifies the filtered inbound RF signal and the mixing section mixes the amplified inbound RF signal with a local oscillation to produce an inbound IF signal. The receiver IF to baseband section converts the inbound IF signal into one or more inbound symbol streams. Filtering may be prior or after amplification by the LNA. | 05-22-2014 |
| 20140153678 | Estimating Optimal Linear Regression Filter Length for Channel Estimation - Techniques for obtaining smoothed channel response estimates in a communications receiver. An example method begins with obtaining ordered channel measurement samples for a current estimation interval and continues with the estimation of a short-term slope value for each of several sequential observation time intervals. A distortion metric is calculated for each of a plurality of candidate filter lengths, where each candidate filter length is an integer multiple of the uniform length. The distortion metric is based on the short-term slope values for observation time intervals falling within the candidate filter length, and characterizes the extent to which the candidate filter length will introduce tracking bias in subsequent signal processing. A filter length is then selected for use in demodulating a received signal from at least among the candidate filter lengths, based on the distortion metric values. | 06-05-2014 |
| 20140153679 | System for and Method of Removing Unwanted Inband Signals from a Received Communication Signal - A system for and method of removing one or more unwanted inband signals from a received communications signal is described. The inband signal or signals may comprise noise, interference signals, or any other unwanted signals that impact the quality of the underlying communications. A receiver receives a communication signal, the received communication signal including the desired communication signal and one or more inband signals. A signal separator processes the received signal to form an estimate of the desired communication signal and an estimate of the inband signals. A performance improver processes the received signal and the estimate of the one or more inband signals to form an improved estimate of the desired communication signal and an improved estimate of the inband signals. | 06-05-2014 |
| 20140169512 | DIRECT CONVERSION RECEIVER INCLUDING A CHARGE AREA DECIMATION FILTER - A direct conversion receiver includes: a high linearity mixer device including a sampler unit charge-sampling an input current according to a sampling frequency, and a buffer unit receiving an output signal from the sampler unit while having a low input impedance, amplifying the received signal, and outputting a current signal; and a filter device decimating an output signal from the mixer device and FIR-filtering the decimated signal. | 06-19-2014 |
| 20140198886 | METHOD AND APPARATUS FOR FILTERING AND COMBINING MULTIPATH COMPONENTS OF A SIGNAL RECEIVED AT MULTIPLE ANTENNAS ACCORDING TO A WIRELESS COMMUNICATION PROTOCOL STANDARD FOR FILTERING A SIGNAL RECEIVED BY A SINGLE ANTENNA - A receiver communicating according to a wireless communication protocol standard for filtering a signal received at a single antenna. The receiver includes filter modules, receiver modules, and a summer. The filter modules receive from antennas multipath components of the signal as transmitted to the receiver. The signal includes bits of data. Each of the filter modules: receives corresponding ones of the multipath components of the signal as received at a respective one of the antennas; and according to the wireless communication protocol standard, filters the signal as received at the respective one of the antennas to generate a filtered signal. The receiver modules respectively receive the filtered signals. Each of the receiver modules combines the multipath components in the respective filtered signal to generate an output signal. Each of the output signals includes a respective version of the bits of data. The summer sums the output signals. | 07-17-2014 |
| 20140198887 | METHOD AND DEVICE FOR MAINTAINING THE PERFORMANCE QUALITY OF A COMMUNICATION SYSTEM IN THE PRESENCE OF NARROW BAND INTERFERENCE - A system that incorporates teachings of the subject disclosure may include, for example, a method for analyzing a wide frequency band with respect to signal power levels in specified narrow frequency bands, detecting narrow band signal power levels received in the specified narrow frequency bands, determining an average composite wideband power level from the narrow band signal power levels, determining an adaptive threshold from the average composite wideband power level, detecting narrow band interference according to the adaptive threshold, and configuring a filter to substantially suppress the detected narrow band interference. Other embodiments are disclosed. | 07-17-2014 |
| 20140211892 | Method and Arrangement in Wireless Communications System - The present invention relates to a receiving node, and to a related method of adjusting a frequency domain channel estimate in a receiving node of a wireless communication system using Orthogonal Frequency Division Multiplexing. The method comprises estimating ( | 07-31-2014 |
| 20140219405 | Delta-Pi Signal Acquisition - Values representative of modulation signal components are extracted from a modulated signal. The modulated signal contains a modulation signal. A periodic time segment sequence is defined having at least four ordered time segments. Multiple sets of signal values are acquired from the modulated signal. For each signal value, a difference in the modulated signal during each of two of the ordered time segments is acquired, as the signal value. The two ordered time segments differ in their order within the sequence by half of the number of ordered time segments in the sequence. Each set is acquired over multiple repetitions of the periodic time segment sequence. Each set is acquired during different ordered time segments than each other set. Each signal value is representative of a modulation signal component. | 08-07-2014 |
| 20140270021 | MULTIMODE RECEIVER WITH COMPLEX FILTER - One aspect of the present invention includes a radio frequency (RF) receiver having a first mixer and a second mixer. The first mixer may be an I-mixer and the second mixer a Q-mixer for downconverting the received RF signal. An impedance circuit is disposed between the first mixer and the second mixer to decouple the channels. In another aspect of present invention, the RF receiver includes a digital filter having at least one complex coefficient. The digital filter exhibits asymmetrical frequency response, and may be used to compensate the asymmetrical frequency response of another filter in the RF receiver. | 09-18-2014 |
| 20140270022 | DATA SIGNAL CORRECTION CIRCUIT, RECEIVER, AND DATA SIGNAL CORRECTION METHOD - A data signal correction circuit includes a channel characteristic calculator unit configured to calculate a channel characteristic estimate value of a received data signal on the basis of a pilot signal, a path detector unit configured to determine a delay quantity of multipath propagation of the received data signal on the basis of the calculated channel characteristic estimate value, and an adaptive filter configured to receive the delay quantity and the channel characteristic estimate value as input items, adjust an input interval of the channel characteristic estimate value along a carrier frequency axis in accordance with the delay quantity, and perform adaptive equalization on the channel characteristic estimate value inputted to the adaptive filter at the adjusted input interval. | 09-18-2014 |
| 20140286465 | WIDEBAND DIGITAL SPECTROMETER - A processor, comprising a first data input configured to receive a stream of samples of a first signal having a spectral space, the stream having a data rate of at least 4 GHz; a second data input configured to receive a stream of samples of a second signal; a multitap correlator, configured to receive the first stream of samples and the second stream of samples, and producing at least one correlation output for each respective sequential sample of the first signal received; and a programmable control configured to alter a relationship of the stream of samples of the first signal and the stream of samples of the second signal, to thereby select, under program control, an alterable correlation output. | 09-25-2014 |
| 20140307840 | DIGITAL IIR FILTER WITH ADJUSTABLE FILTER WEIGHTS BASED ON MEASURED CHANGES IN THE PROCESSED DATA - A digital filter receives a sequence of input signal values. A filtering block performs a filtering operation on sequence of input signal values that is controlled by filter coefficients. A control block also receives the sequence of input signal values. The control block evaluates detected changes over time with respect to the sequence of input signal values and selects values for the filter coefficients based on the detected changes. The detected change over time provides an indication of the whether the sequence of input signal values is changing signal state. If so, the filter coefficients are selected to emphasize signal response time over signal noise filtering for the filtering operation. Otherwise, the filter coefficients are selected to emphasize signal noise filtering over signal response time for the filtering operation. | 10-16-2014 |
| 20140307841 | SNR Dependent Channel Tracking For SUN OFDM - An orthogonal frequency-division multiplexed (OFDM)-based receiver for channel tracking with signal-to-noise ratio dependent parameters that includes a memory; and a signal processor, coupled to the memory. The signal processor to estimate a signal-to-noise ratio (SNR) for a received packet of OFDM symbols and determine an SNR region in which the SNR estimate falls, wherein the signal processor implements a different set of finite impulse response (FIR) filter coefficients for each SNR region. | 10-16-2014 |
| 20140328440 | FILTER CIRCUIT AND RECEIVING APPARATUS - A receiving apparatus that includes a first and second filter circuit. The first filter performs filtering on a frequency signal with a band-pass characteristic such that a frequency band of a desired channel is included in a passband, thereby obtaining a pass frequency signal. The second filter performs filtering on the pass frequency signal with a filter characteristic such that a frequency band of a channel adjoining the desired channel is included in an attenuation band. | 11-06-2014 |
| 20140341326 | CHANNEL ESTIMATION WITH DISCONTINUOUS PILOT SIGNALS - Methods, systems, and apparatuses to estimate a channel with discontinuous instances of a pilot signal. A pilot signal is received during a first and second time period. The time periods are separated by a blank period. The pilot signal is not received during the blank period. A pilot signal received during the second time period is combined with a pilot signal received during the first time period. A channel estimate is based on the combination. According to a second method, pilot signals are received. A first and second channel estimate is calculated based on the pilot signals. Data symbols are received following the pilot signals. A third channel estimate is extrapolated from the channel estimates. This channel estimate corresponds to a virtualized instance of the pilot signal. The data symbols are interpolated based on the second and third channel estimates. | 11-20-2014 |
| 20140348276 | SYSTEM AND METHOD FOR OPERATING A FILTER FOR ECHO CANCELLATION - Systems and methods for operating a filter for echo cancellation are described. In one embodiment, a method for operating a filter for echo cancellation involves monitoring at least one of a filter coefficient of the filter and an echo cancellation error to generate a monitoring result and, in response to the monitoring result, adjusting at least one of delay elements and filter taps of the filter to vary an impulse response of the filter. Other embodiments are also described. | 11-27-2014 |
| 20140348277 | Differential Phase Tracking in the Presence of Unknown Interference - Example embodiments comprise a diversity receiver, and corresponding method, for measuring a differential phase between a first local oscillator of a first antenna and a second local oscillator of a second antenna in the presence of a primary interference signal and at least one secondary interference signal. The method may comprise receiving a primary communication signal, a primary reference signal and additional reference signals, and processing these signals such that a summation signal does not substantially comprise the at least one secondary interference signal. The estimation of differential phase is achieved by a phase shift calculation between processed signal components, using that a summation of all signal components equals, or is approximately equal to, a predetermined signal. | 11-27-2014 |
| 20140369452 | METHOD AND APPARATUS FOR ON-DEMAND INTERFERENCE REJECTION IN MULTI-BAND GNSS RECEIVERS - In general, the present invention relates to an adaptive IF filter for a multiband receiver. According to certain aspects, the adaptive IF filter can be dynamically configured as a low-pass architecture or a complex band-pass architecture. According to further aspects, the adaptive IF filter enables a wideband receiver which can simultaneously receive multiple frequency bands, but still protect itself from close-in or in-band jammers by selecting a single frequency band or subset of frequency bands. This retains the multiband functionality of the receiver under nominal conditions, which is traded off dynamically for a single-frequency-band with high jammer resistance under severe jamming conditions. According to still further aspects, the approach of the invention is particularly useful for GNSS receivers, since unlike a cellular transceiver, a temporary loss of signal is not catastrophic to GNSS receivers due to the long integration times. | 12-18-2014 |
| 20140376673 | METHOD AND SYSTEM FOR I/Q MISMATCH CALIBRATION AND COMPENSATION FOR WIDEBAND COMMUNICATION RECEIVERS - Methods and systems for I/Q mismatch calibration and compensation for wideband communication receivers may include receiving a radio frequency (RF) signal in a receiver of a communication device, down-sampling the received RF signal to generate a channel k and its image channel −k at baseband frequencies, and determining average in-phase (I) and quadrature (Q) gain and phase mismatch of the channel k and the image channel −k. A curvature of gain mismatch for the channel k and the image channel −k may be estimate utilizing a blind source separation (BSS) estimation algorithm. The average I and Q gain and phase mismatch of the channel k and the image channel −k may be removed. A residual phase tilt and a residual amplitude tilt of the channel k and the image channel −k (with removed average I and Q gain and phase mismatch) may be determined. | 12-25-2014 |
| 20150010120 | SUPER-REGENERATIVE RECEIVING METHOD AND SUPER-REGENERATIVE RECEIVER (SRR) CIRCUIT WITH HIGH FREQUENCY SELECTIVITY - A super-regenerative receiver (SRR) circuit includes an amplifier configured to amplify an input injection signal and output the amplified injection signal to an oscillator; and a feed-forwarding unit configured to feed-forward, to the oscillator, a filtered signal obtained by filtering the injection signal after converting a frequency of the injection signal to another frequency; wherein the oscillator is configured to receive an input of a signal in which the filtered signal is applied to the injection signal. | 01-08-2015 |
| 20150023457 | SYSTEM AND METHOD FOR PROCESSING A SIGNAL RECEIVED FROM A MICROELECTROMECHANICAL SYSTEM - System for processing a signal received from a microelectromechanical system, comprising means for sampling said received signal at a sampling frequency (F | 01-22-2015 |
| 20150030110 | IMPULSE NOISE MITIGATION UNDER OUT-OF-BAND INTERFERENCE CONDITIONS - An impulse noise mitigation circuit (INMC) may set a cut-off frequency of each of two high pass filters to bound a frequency bandwidth of a desired signal, wherein a first of the two filters allows frequencies higher than the frequency bandwidth of the desired signal, and a second of the two filters allows frequencies lower than the frequency bandwidth of the desired signal. The INMC may compute and store a mean magnitude separately for a first signal response of the first filter and a second signal response of the second filter. The INMC may select the first filter for impulse noise mitigation when the mean magnitude of the second filter is greater than the mean magnitude of the first filter. The INMC may select the second filter for impulse noise mitigation when the mean magnitude of the first filter is greater than the second filter. | 01-29-2015 |
| 20150055737 | DITHER-LESS MULTI-STAGE NOISE SHAPING FRACTIONAL-N FREQUENCY SYNTHESIZER SYSTEMS AND METHODS - A fractional-N divider of a frequency synthesizer is driven by a dither-less and seed-less multi-stage noise shaping (MASH) modulator to alleviate fractional spurious tones introduced by the cyclic train of division ratios from delta-sigma modulators. The MASH modulator includes at least two cascaded dither-less delta-sigma modulators where each modulator includes a first feedback loop the generates the modulator feedback signal, a second feedback loop that disrupts fractional spurious tones and a third feedback loop that provides approximately zero static error. The MASH modulator further includes a combining circuit delays at least one code sequence from at least one of the delta-sigma modulators and that combines the code sequence generated by each of the delta-sigma modulators and at least one delayed code sequence. | 02-26-2015 |
| 20150055738 | DITHER-LESS ERROR FEEDBACK FRACTIONAL-N FREQUENCY SYNTHESIZER SYSTEMS AND METHODS - A fractional-N divider of a frequency synthesizer is driven by a dither-less error feedback modulator to alleviate fractional spurious tones introduced by the cyclic train of division ratios from delta-sigma modulators. A first feedback loop generates the feedback signal. A second feedback loop disrupts fractional spurious tones and a third feedback loop provides approximately zero static error. | 02-26-2015 |
| 20150063509 | BLOCKER FILTERING FOR NOISE-CANCELLING RECEIVER - Techniques for improving rejection of out-of-band interference in a noise-cancelling receive architecture. In an aspect, capacitors blocking in-band signals and passing through out-of-band signals destructively couple an auxiliary mixer output to a mixer output. In a further aspect, cross-coupling capacitors are provided to couple a first signal path with a second signal path of the noise-cancelling receive signal path. Baseband poly phase cross-coupling blocker filtering is further provided for out-of-band interference cancellation to create notch responses at blocker offset frequencies. The techniques disclosed may readily be adapted for multi-phase local oscillator systems. | 03-05-2015 |
| 20150071392 | METHOD AND APPARATUS FOR REDUCING FM AUDIO ARTIFACTS IN A RECEIVER - An apparatus and method for reducing FM audio artifacts in a receiver are provided. A direct conversion radio frequency (RF) receiver converts an analog FM signal into a phase shifted digital low IF signal. A digital controller coupled to the analog FM receiver provides adaptive frequency translation for different channel spacing and provides adaptive low IF configuration through the different channel spacing, thereby suppressing audio artifacts. | 03-12-2015 |
| 20150098533 | Method for Detection of Symbols in Communication Signals - The present invention relates to method for detection of symbols, comprising: receiving at least one communication signal y transmitted over a radio channel H, and receiving a priori LLRs of said channel inputs x; computing soft symbol estimates μ and variance D of said channel inputs x based on LLRs of said channel inputs x; filtering and interference cancelling said received signal y by using a first filter and filtered soft symbol estimates μ so as to obtain a filtered and interference cancelled received signal; estimating MSE matrix B of said filtered and interference cancelled received signal; computing an optimal matrix G | 04-09-2015 |
| 20150098534 | Ingress Cancellation Tachometer - Indication of an amount of processing performed in detection and removal of ingress noise may be provided. A frequency domain representation of a narrowband region of a digital input signal may be received. The received frequency domain representation of the narrowband region may be compared with a predetermined threshold. Results from the comparison of the received frequency domain representation of the narrowband region with the predetermined threshold may be aggregated. Based on the aggregated results, an indication of an amount of processing performed by an ingress exciser in removing the ingress noise may be provided. | 04-09-2015 |
| 20150098535 | PHASE NOISE MITIGATION FOR WIRELESS COMMUNICATIONS - A method and apparatus for tracking and mitigating phase noise in a communication receiver are disclosed. The phase noise tracking and mitigation apparatus operates in a recursive manner and includes a quantizer for determining data symbols from noise-compensated input values, a phase noise estimator for determining raw phase noise values from the data symbols and a first sequence of uncompensated input values, an error concealment module for removing unreliable samples from the raw phase noise values, a filter operable to filter the raw phase noise values to produce filtered phase noise values, and a phase-noise compensator for determining noise-compensated output values dependent upon the filtered phase noise values and the first sequence of uncompensated input values. Filter coefficients, and initial noise-compensated input values are determined from one or more second sequences of uncompensated input values corresponding to known symbols corrupted by phase noise. | 04-09-2015 |
| 20150117577 | WIRELESS COMMUNICATION RECEIVER WITH I/Q IMBALANCE ESTIMATION AND CORRECTION TECHNIQUES - Techniques are provided that utilize information on the characteristics of the transmitted signal to improve the accuracy of the I/Q imbalance estimation and correction. These techniques can be used to achieve improved image rejection performance over existing solutions, through the use of signal conditioning, windowing and the use of statistical information on the received signal. A number of techniques aimed at improving the accuracy of the I/Q imbalance estimation/correction are presented, including different modes of I/Q imbalance estimation and I/Q imbalance correction in the presence of a complex IF filter in the transceiver. The processing is performed mostly in the DBB in order to be area/power efficient. | 04-30-2015 |
| 20150295602 | COMMUNICATION APPARATUSES - A communication apparatus includes a first communication module, a second communication module, an antenna module and a filtering module. The first communication module transmits and receives a first RF signal on a first channel. The second communication module transmits and receives a second RF signal on a second channel. The antenna module includes multiple antennas for transmitting and receiving the first and second RF signals. The filtering module is coupled between the first and second communication modules and the antenna module. The filtering module filters the first RF signal according to a first frequency response, and it filters the second RF signal according to a second frequency response to ensure the first RF signal and the second RF signal do not interfere with each other. | 10-15-2015 |
| 20150303956 | FIRST ADJACENT CANCELLER (FAC) WITH IMPROVED BLENDING USING A PARAMETRIC FILTER - A method for processing a radio signal includes: receiving an FM in-band on-channel radio signal including a plurality of digitally modulated subcarriers in upper and lower sidebands; sampling the FM in-band on-channel radio signal to produce an input signal including complex digital samples of a combination of a desired one the upper and lower sidebands and an FM interferer; removing FM interferer components from the first signal by notch filtering to produce a notch-filtered signal; weighting the notch-filtered signal to produce a weighted notch-filtered signal; using a parametric filter to filter the input signal to produce a parametric-filtered input signal; and combining the weighted notch-filtered signal and the parametric-filtered input signal to produce an output signal. A radio receiver that implements the method is also included. | 10-22-2015 |
| 20150303957 | RF RECEIVER AND DIGITALLY-ASSISTED CALIBRATION METHOD APPLICABLE THERETO - A radio frequency (RF) receiver includes a digital tuning engine; and I-path and Q-path analog filters, tuned by the digital tuning engine. The digital tuning engine gets an I/Q imbalance difference, and the digital tuning engines tunes the I-path analog filter and/or the Q-path analog filter based on the I/Q imbalance difference. | 10-22-2015 |
| 20150304150 | LOW COMPLEXITY NARROWBAND INTERFERENCE SUPPRESSION - In one embodiment a method for suppressing narrowband interference in an RF signal is provided. The method includes providing a block of baseband digital samples of the RF signal and computing n-1 stages of an n stage fast Fourier transform (FFT) on the block of the baseband digital samples to produce a first block of intermediate data points. A final threshold is computed based on values of the intermediate data points. A final stage of the n stage FFT is computed from the first block of intermediate data points to produce a block of output data points, and the output data points that have an energy above the final threshold are attenuated. | 10-22-2015 |
| 20150311928 | ADAPTIVE RADIO-FREQUENCY INTERFERENCE CANCELLING DEVICE, METHOD, AND RECEIVER - The present invention provides an adaptive radio-interference cancelling device and method, a receiver, and a wireless full duplex communication system. The device includes an amplitude phase adjusting module, configured to adjust an amplitude and a phase of a radio-frequency reference signal and output a radio-frequency adjustment signal to enable the radio-frequency adjustment signal to converge to a self-interference signal in a radio-frequency received signal; a subtractor, configured to output a radio-frequency residual signal, where the radio-frequency residual signal is a difference signal between the radio-frequency received signal and the radio-frequency adjustment signal; and a baseband extracting and filtering module, configured to receive the radio-frequency reference signal and the radio-frequency residual signal output by the subtractor, extract baseband signals and perform least mean squares adaptive filtering processing on the baseband signals to obtain an amplitude phase control signal and output to the amplitude phase adjusting module. | 10-29-2015 |
| 20150312057 | CHANNEL ESTIMATION METHOD AND DEVICE - A channel estimation method, comprising: a channel estimation device employs a two-dimensional channel estimation method and utilizes the channel estimate of an original pilot frequency to conduct channel estimation on an encrypted pilot frequency, so as to obtain the channel estimate of the encrypted pilot frequency; the channel estimation device employs a one-dimensional channel estimation method and utilizes the channel estimate of the encrypted pilot frequency to conduct channel estimation on all resources, so as to obtain the channel estimates on all resources. | 10-29-2015 |
| 20150318884 | RADIOFREQUENCY SIGNAL RECEIVER DESIGNED TO BE INSTALLED ON A SATELLITE - A receiver for radiofrequency signals designed to be installed on board a satellite comprises: a device for frequency controlling the receiver allowing the reception frequency of the receiver to be adjusted based on a frequency command; and a filtering assembly of the bandpass filter type having a passband, referred to as passband of the filtering assembly, having an adjustable passband width able to take a set of values, the filtering assembly allowing the bandwidth of a first signal representative of the input signal of the receiver to be limited to the passband of the filtering assembly; adjustment means allowing the width of the passband of the filtering assembly to be adjusted using a filtering passband control; power acquisition means allowing a measurement of the power of the first signal to be delivered at the output of the filtering assembly. | 11-05-2015 |
| 20150333785 | SAW-LESS, LNA-LESS LOW NOISE RECEIVER - A low noise receiver includes a downconverter configured to receive a radio frequency (RF) signal, the downconverter comprising a switching architecture configured to generate a plurality of output phases based on a respective plurality of local oscillator (LO) signals, a differencing circuit configured to combine the plurality of output phases such that an nth output phase is differenced with an (n+K)th output phase, resulting in gain-added output phases, and a summation filter configured to receive the gain-added output phases and configured to combine the gain-added output phases such that a response of the receiver effectively reduces odd harmonics of the RF signal. | 11-19-2015 |
| 20150358042 | Nonlinear Filtering Using Polyphase Filter Banks - A method and apparatus for analyzing an input signal. A nonlinear filter system comprises a plurality of polyphase filter banks corresponding to a plurality of orders of nonlinearity. Each of the plurality of polyphase filter banks is configured to process an input signal with respect to a plurality of selected frequency subbands to generate an output signal that corresponds to a corresponding order of the each of the plurality of polyphase filter banks. | 12-10-2015 |
| 20150365261 | ALTERNATING PHASE FILTER FOR INCREASING COMMUNICATION SPEEDS, SPECTRAL EFFICIENCY AND ENABLING OTHER BENEFITS - Common wave and sideband mitigation communication systems and methods are provided that can be used with both wireless and wired communication links. The systems and methods provided can enable faster data rates, greater immunity to noise, increased bandwidth/spectrum efficiency and/or other benefits. Applications include but are not limited to: cell phones, smartphones (e.g., iPhone, BlackBerry, etc.), wireless Internet, local area networks (e.g., WiFi type applications), wide area networks (e.g., WiMAX type applications), personal digital assistants, computers, Internet service providers and communications satellites. | 12-17-2015 |
| 20150381222 | Detection and Mitigation of Interference in a Receiver - A receiver architecture optimizes receiver performance in the presence of interference. In various embodiments, power estimation circuits are used with variable selectivity to determine the exact nature of the interference and to optimize the performance correspondingly. The variable selectivity is achieved using stages of filtering with progressively narrower bandwidths. Also, the actual method of optimizing the receiver performance is an improvement compared to the traditional techniques in that the gain settings and the baseband filter order (stages to be used) will be optimized based on the nature of the interference as determined by the power detector measurements. For a device such as a cellular phone that operates in a dynamic and changing environment where interference is variable, embodiments advantageously provide the capability to modify the receiver's operational state depending on the interference. | 12-31-2015 |
| 20160006466 | PROGRAMMABLE HETERODINE ACTIVE FILTER FOR TELECOMMUNICATIONS RECEIVERS - The present invention relates to a programmable filtering system that allows the telecommunications receivers to maintain and improve their reception quality against high levels of noise floor and/or the presence of unwanted signals. The filtering system is portable and of a compact size, similar to the telecommunications receiver. | 01-07-2016 |
| 20160006585 | CONTINUOUS PHASE MODULATION METHOD AND EMITTER IMPLEMENTING SAID METHOD - A continuous phase modulation method comprises the following steps: receiving a sequence of digital data symbols a(n) to be emitted; transforming the sequence of symbols a(n) to be emitted into a transformed sequence of symbols b(n), each symbol b(n) of which is equal to the sum of a symbol a(n) to be emitted and of a corrective factor equal to a transformation Tf applied to a plurality of differences (a(n)-a(n−1)) between two consecutive symbols to be emitted, the transformation Tf applied being a combination c of at least two differences between two consecutive symbols of the sequence to be emitted, transformed by the application of a non-linear function ƒ; filtering the sequence of transformed symbols b(n) with a shaping filter and modulating the filtered sequence with a phase modulator; said transformation Tf being defined so as to minimize interference between modulated symbols filtered by a receiving filter. | 01-07-2016 |
| 20160006592 | BLIND PHASE TRACKING METHOD FOR FBMC RECEIVER - A blind phase tracking method for an FBMC receiver. The frequency components of the received signal, after translation into baseband and filtered by an analysis filter bank, is processed by a phase estimation module. The latter estimates for each subcarrier the data carried and, where appropriate, the interference generated by the other data. A simplified symbol is then constructed with the sign of the data thus estimated and, where appropriate, the sign of the interference thus estimated. The phase estimation module determines the phase from the frequency components and simplified symbols. The phase correction is performed by multiplication by a phase correction factor. | 01-07-2016 |
| 20160013816 | Adaptive/Configurable Intermediate Frequency (IF) Wireless Receiver And Bluetooth Device Using The Same | 01-14-2016 |
| 20160020795 | APPARATUS AND METHODS FOR SIGNAL GENERATION, RECEPTION, AND SELF-CALIBRATION - Apparatus and methods for signal generation, reception, and calibration involving quadrature modulation and frequency conversion. Embodiments of the present invention provide extremely wide bandwidth, high spectral purity, versatility and adaptability in configuration, and ease of calibration, and are particularly well-adapted for use in integrated circuitry. | 01-21-2016 |
| 20160020796 | Multidrop Data Transfer - Multi-drop communications channels can have significantly deep notches in their frequency response causing a corresponding limitation of the effective data transmission rate. A special time-ordered coding method is described which results in the emitted spectrum of the data stream transmitted into the channel having a notch at the same frequency as the notch in the channel frequency response, permitting channel receivers to successfully decode the transmitted data stream. The described coding method may be applied at various multiples of the channel notch frequency to support different throughput rates, and may be combined with other coding techniques such as group or vector signaling codes. | 01-21-2016 |
| 20160043756 | Mixer Sequence Design For N-Path Filters - A bandpass filter includes a plurality of parallel paths, each receiving the input signal to the bandpass filter. Each path includes a first mixer, a low-pass filter, and a second mixer. The first mixer in each path is coupled to receive the input signal and mixes the input signal with a periodic mixer sequence having a period that is divided into a plurality of time slots. The mixer value is constant during each time slot. The low-pass filter in each path is operable to filter an output of the associated first mixer. The second mixer in each path is coupled to receive an output of the associated low-pass filter and mixes said filter output with a periodic mixer sequence having a period that is divided into a plurality of time slots, wherein again the mixer value is constant during each time slot. A summer sums the outputs of the second mixers of each of the paths to generate an output of the bandpass filter. | 02-11-2016 |
| 20160049971 | IMPULSE NOISE MITIGATION UNDER OUT-OF-BAND INTERFERENCE CONDITIONS - An impulse noise mitigation circuit (INMC) may set a cut-off frequency of each of two high pass filters to bound a frequency bandwidth of a desired signal, wherein a first of the two filters allows frequencies higher than the frequency bandwidth of the desired signal, and a second of the two filters allows frequencies lower than the frequency bandwidth of the desired signal. The INMC may compute and store a mean magnitude separately for a first signal response of the first filter and a second signal response of the second filter. The INMC may select the first filter for impulse noise mitigation when the mean magnitude of the second filter is greater than the mean magnitude of the first filter. The INMC may select the second filter for impulse noise mitigation when the mean magnitude of the first filter is greater than the second filter. | 02-18-2016 |
| 20160065404 | METHOD AND SYSTEM FOR I/Q MISMATCH CALIBRATION AND COMPENSATION FOR WIDEBAND COMMUNICATION RECEIVERS - Methods and systems for I/O mismatch calibration and compensation for wideband communication receivers may include receiving a radio frequency (RF) signal in a receiver of a communication device, down-sampling said received RF signal to generate a channel k and its image channel −k at baseband frequencies, determining average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k, removing said average I and Q gain and phase mismatch of said channel k and said image channel −k, determining, after said removing said average I and Q gain and phase mismatch, a residual phase tilt of said channel k and said image channel −k, and compensating for said determined residual phase tilt of said channel k and said image channel −k utilizing a phase tilt correction filter. | 03-03-2016 |
| 20160079945 | PROGRAMMABLE IMPEDANCE NETWORK IN AN AMPLIFIER - The disclosure provides an amplifier. The amplifier includes a first transistor that receives a first input. A second transistor receives a second input. A plurality of impedance networks is coupled between the first transistor and the second transistor. At least one impedance network of the plurality of impedance networks includes a first impedance path and a second impedance path. The first impedance path is activated during single ended operation, and the second impedance path is activated during differential operation. | 03-17-2016 |
| 20160094376 | METHODS AND SYSTEMS FOR DUAL-USING A RECEPTION CHANNEL - Various embodiments of wireless communication systems and methods in which the system seamlessly dual-uses a receiver chain for incoming transmissions and for other signal sensing purposes. The system is configured such that there are multiple receiver chains, and at least one receiver chain alternates between receiving a communication signal with information payload and receiving other signals solely for the purposes of monitoring and/or improving some aspects of the system. In various embodiments, the alternating receiver chain receives alternatively signals with information payloads and signals which have passes through a power amplifier with amplifier distortion characteristics. In various embodiments, the alternating receiver chain receives alternatively signals with information payloads and signals which may be associated with background noise, or other radio transmissions. | 03-31-2016 |
| 20160126988 | BROADBAND SUPERHETRODYNE RECEIVER WITH AGILE INTERMEDIATE FREQUENCY FOR INTERFERENCE MITIGATION - A broadband superheterodyne receiver. Embodiments include an input for receiving an RF signal including an RF data signal at a carrier frequency. An RF mixer coupled to the input shifts the RF data signal from the carrier frequency to an IF frequency. An IF band pass filter coupled to the mixer has a pass band, and band pass filters the signal near the IF frequency. A spectrum analyzer provides information representative of the spectral characteristics of the received RF signal around the RF data signal at the carrier frequency. An IF controller is coupled to the RF mixer and to the spectrum analyzer. The IF controller: (1) determines an interference-mitigating IF frequency within the pass band of the band pass filter that will result in attenuation of undesired portions of the RF signal, and (2) controls the RF mixer to shift the RF data signal to the interference-mitigating IF frequency. | 05-05-2016 |
| 20160126991 | DIGITAL FILTER FOR NARROWBAND INTERFERENCE REJECTION - A digital filter for narrowband interference rejection, including modules of narrowband interference rejection connected in series, each of which includes the following elements connected in series: a block of successive vector rotation based on the CORDIC vector rotation algorithm for integers, a block of reduction of the length of the rotated vector to maintain the same number of bits for digital signal representation, a block of high-pass filters for orthogonal components of the reduced vector in order to remove the interference from zero frequency region. The filter can be implemented without multiplication. | 05-05-2016 |
| 20160156487 | TRANSMISSION APPARATUS AND METHOD USING PRE-DISTORTION | 06-02-2016 |
| 20160164555 | Mixer Sequence Design for N-Path Filters - A bandpass filter includes a plurality of parallel paths. Each path includes a first mixer, a low-pass filter, and a second mixer. The first mixer in each path receives the input signal and mixes the input signal with a periodic mixer sequence. The low-pass filter in each path is operable to filter an output of the associated first mixer. The second mixer in each path is coupled to receive an output of the associated low-pass filter and mixes said filter output with a periodic mixer sequence having a period that is divided into a plurality of time slots, wherein again the mixer value is constant during each time slot. A summer sums the outputs of the second mixers of each of the paths to generate an output of the bandpass filter. | 06-09-2016 |
| 20160380660 | Methods and Apparatus for Reducing Noise, Power and Settling Time in Multi-Modal Analog Multiplexed Data Acquisition Systems - Reduced noise and power with rapid settling time and increased performance in multi-modal analog multiplexed data acquisition systems. An example apparatus arrangement includes a circuit input configured to receive a plurality of analog input signals; an analog to digital converter circuit configured to output a digital representation of an analog voltage; a selection circuit configured to select one of the analog input signals received at the circuit input; a buffer coupled to receive the selected one of the analog input signals; a filter coupled to the buffer and configured to perform a high bandwidth sample operation and a low bandwidth sample operation and having a filter output, responsive to a control signal; and a sampling capacitor coupled to the filter to sample the filter output, and having an output coupled to the analog to digital converter. Methods and additional apparatus arrangements are disclosed. | 12-29-2016 |
| 20170237508 | Device and Method of Handling Soft Information | 08-17-2017 |
| 20180026665 | Channel Selection Filter Compensation | 01-25-2018 |
