Entries |
Document | Title | Date |
20080205535 | Touch screen, location finder, GSM, EDGE, CDMA cellular and OFDM, Wi-Fi system - Interactive touch screen controlled communication systems for single or multimode communications and broadcasting. Processor for processing multiple touch screen signals, obtained by touching the screen of a device. Processor for receiving and processing multiple signals received from multiple locations and for generating a processed position finder signal. Processor and filter for generating time division processed filtered signal used in Time Division Multiple Access (TDMA) Global Mobile System (GSM), Enhanced Digital GSM Evolution (EDGE), in Code Division Multiple Access (CDMA) and in Orthogonal Frequency Division Multiplex(OFDM), Wi-Fi wireless fidelity (Wi-Fi) systems. Processor for generating cross-correlated in-phase and quadrature-phase processed filtered baseband signals from an input signal. Processor for generating a signal from processing of the processed touch screen signal with processed position finder signal and with one or more of the signals generated by the other processors. Modulator for modulation of the signal generated by one or more of the processors. Transmitter for transmission of the modulated signal and receiver and demodulator for receiving and demodulating said transmitted signal. System with multiple received signals received from two or more satellite transmitters and from two or more land based transmitters. A system wherein cross-correlated in-phase and quadrature-phase processed filtered baseband signals and processed spread spectrum signal are used in a cellular communication system and orthogonal frequency division multiplex signal is used in a wireless local area network. | 08-28-2008 |
20080205536 | I/Q REGENERATION DEVICE OF FIVE-PORT NETWORK - There is provided an I/Q regeneration device of a five-port network which adopts a single-frequency continuous wave signal in place of a specific modulated signal such as a QPSK signal to estimate an I/Q regeneration parameter of the five-port network. The I/Q regeneration device of the five-port network including: a five-port network distributing an input signal as three signals and adding the three signals to first, second and third carrier signals, respectively to output first, second and third phase signals each having a phase different from one another; a power detection part detecting a power of each of the first, second and third phase signals from the five-port network to output first, second and third power detection signals; and a post-processing part restoring original data in response to the first, second and third power detection signals. | 08-28-2008 |
20080219372 | OFDM MODULATOR - An OFDM modulator having a peak factor reduction function. The OFDM modulator has a peak factor reduction unit between an IFFT unit and a guard interval insertion unit thereof. The peak factor reduction unit converts a complex signal X | 09-11-2008 |
20080225973 | Device and method for determining a constellation of a quadrature amplitude modulated signal - The invention relates to a method and/or a device for determining a constellation from a plurality of possible constellations with a constellation identification device which is used to determine the constellation of the signal from a plurality of possible constellations. This is advantageously achieved when a converter is arranged to convert the signal into polar coordinates provided with a radial component, and to provide a radius as a radial component of the signal, wherein the constellation identification device is constructed so as to determine the constellation of the signal from the radius. | 09-18-2008 |
20080232498 | RADIO RECEIVER OR TRANSMITTER AND METHOD FOR REDUCING AN IQ GAIN IMBALANCE - A radio receiver includes an in-phase channel and a quadrature channel, the channels being provided in parallel at a respective input with quadrature modulated radio frequency signals; and an error correction loop for detecting and correcting an imbalance in gain between at least part of the in-phase channel and a corresponding part of the quadrature channel, wherein the error correction loop comprises: a detector adapted to calculate Error_det | 09-25-2008 |
20080232499 | METHOD OF APPROXIMATING LOG-LIKELIHOOD RATIOS IN QAM DIGITAL TRANSMISSIONS AND RELATIVE QAM SOFT-OUTPUT DE-MAPPER - Log-likelihood ratios are approximated for encoded bits modulated with a 2 | 09-25-2008 |
20080260061 | Method for the Coding of an Ofdm/Oqam Signal Using Symbols with Complex Values, and Corresponding Signal, Devices and Computer Programs - A method and apparatus are provided for coding an OFDM/OQAM-type multi-carrier signal formed by a temporal succession of symbols comprising a set of data elements. Each of the data elements modulates a carrier frequency of the signal. Each of the data elements is formed by adding two real values in quadrature, which each correspond to a binary word of a source signal, which is modulated using a pre-determined modulation constellation, such as to transmit information over a real channel and an imaginary channel of the OFDM/OQAM symbols. | 10-23-2008 |
20080273618 | Precoding System and Method for Multi-User Transmission in Multiple Antenna Wireless Systems - A transmission method and system are provided wherein the system and method use precoding and sum rate optimization beam forming to create a capacity transmission. | 11-06-2008 |
20080279298 | MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) DETECTOR INCORPORATING EFFICIENT SIGNAL POINT SEARCH - A novel and useful apparatus for and method of multiple input multiple output (MIMO) detection for use in MIMO based communication systems. The mechanism of the invention performs a simplified tree search utilizing a single stage expansion of the most likely first symbol candidates, in the case of a 2×2 MIMO system. The invention also provides a refinement mechanism that is operative to significantly improve the log likelihood (LLR) of the list of candidates. To improve the LLR, the mechanism applies refinements rounds to generate additional candidates for both first and second detected symbols. | 11-13-2008 |
20080298493 | N-CANDIDATE DEPTH-FIRST DECODING - The problem outlined above may at least in part be addressed by N-Candidate Depth-First Decoding methods and systems that employ such methods. In some embodiments, the method includes receiving data representing a vector of receive signals detected by multiple receive transceivers; performing an N-candidate, depth-first search on the data to obtain an estimated constellation point; and providing a user data stream based at least in part on the estimated constellation point. In some embodiments the system includes a multiple-input multiple-output decoder. The decoder is configured to perform an N-candidate, depth-first search as part of converting a receive signal into a data stream. | 12-04-2008 |
20080317152 | Method and Apparatus for Multi-Carrier Hsdpa Traffic Transmission Channel Coding - Three channel coding schemes for multi-carrier HSDPA packet data transmission are disclosed. The first scheme includes: dividing data into N groups (S | 12-25-2008 |
20090003482 | BROADBAND SELF ADJUSTING QUADRATURE SIGNAL GENERATOR AND METHOD THEREOF - Low noise phase quadrature signals are generated after receiving a clock signal and adjusting the clock signal in response to a feedback signal to generate a phase adjusted clock signal. The clock signal and the phase adjusted clock signal are exclusive-ored to generate a frequency doubled signal. An in-phase local oscillator signal and a quadrature local oscillator signal are generated from the frequency doubled signal such that the in-phase local oscillator and the quadrature local oscillator signal are out-of-phase with each other. In addition, a phase relationship between the in-phase local oscillator signal and the quadrature local oscillator signal are detected, and the feedback signal is generated based upon the phase relationship between the in-phase local oscillator signal and the quadrature local oscillator signal. | 01-01-2009 |
20090016458 | TRANSFERRING DOCSIS FRAMES USING A LABEL SWITCHING NETWORK - In one embodiment, label distribution sessions are established between a Modular Cable Modem Termination System (M-CMTS) core and one or more remote PHYs. The label distribution sessions facilitate association of labels with either Radio Frequency (RF) channels or groups of the RF channels that extend from the remote PHYs to one or more cable modems. The labels are then used to facilitate communications between the M-CMTS core and the remote PHYs over a MultiProtocol Label Switching (MPLS) network. | 01-15-2009 |
20090028261 | METHOD AND APPARATUS FOR REDUCING SIGNALING OVERHEAD DURING A DUAL CODEWORD HYBRID AUTOMATIC REPEAT REQUEST OPERATION - A method and an apparatus for reducing overhead in signaling for downlink dual codewords in a wireless transmit receive unit (WTRU) with spatial multiplexing are disclosed. The method includes signaling a number of codewords to be used, signaling modulation scheme coding, reducing overhead for signaling of transport block size (TBS), and/or reducing overhead for signaling associated with error correction. | 01-29-2009 |
20090034641 | SYSTEM AND METHOD FOR DYNAMIC CALIBRATION OF A QUADRATURE ENCODER - A system and method for real time calibration of a quadrature encoder. Errors from sources such as signal offsets, amplitude mismatches and phase errors are addressed. In one embodiment, the errors are addressed by determining and applying a dynamic operational set of calibration parameters. The process for determining the operational calibration parameters involves minimizing a variation metric that indicates the variations of the magnitudes of a set of corrected vectors Ci″. The corrected vectors Ci″ are defined by using the calibration parameters to provide corrected vector components (Ati″, Bti″) that correspond to a current operational set of quadrature signal samples comprising at least four respective quadrature signal samples (Ati, Bti) having spatial phase angles θti that are distributed over a significant portion of 360 degrees. For well chosen calibration parameters, the resulting corrected vectors define a well-centered circle and the variation metric is minimized. | 02-05-2009 |
20090034642 | METHOD AND SYSTEM FOR POWER SUPPLY ADJUSTMENT AND POLAR MODULATION IN A MIMO SYSTEM - Aspects of a method and system for power supply adjustment and polar modulation in a MIMO system are provided. In each RF transmit chain of a MIMO system that utilizes polar modulation, aspects of the invention may enable generating a signal representative of an amplitude of a pair of phase-quadrature baseband signals; and controlling a voltage and/or current regulator utilizing said generated signal. In this regard, a voltage and/or current supplied to a power amplifier and/or mixer of one or more of the transmit chains may be controlled based on the generated signal. Additionally, a gain of a power amplifier for each RF transmit chain may be controlled utilizing said signal representative of an amplitude. The signal representative of an amplitude may be generated by squaring each of the phase-quadrature baseband signals and calculating a square root of a sum of the squared signals. | 02-05-2009 |
20090041145 | METHOD TO DETECT DATA TRANSMITTED FROM MULTIPLE ANTENNAS AND SYSTEM THEREOF - A method to detect data transmitted from multiple antennas, said method comprising steps of: selecting a starting data block and calling it as previous data block; defining a set of indices of bits to be checked for possible flip in the previous data block as a check candidate set; applying update rule to obtain updated data block using the previous data block and the check candidate set, wherein the update is made in such a manner that change in likelihood is positive; checking if the updated data block and several consecutive previous data blocks are the same; if yes, declare the updated data block as the detected data block; if no, make updated data block as previous data block and repeat updation of data block. | 02-12-2009 |
20090052568 | QAM COMMUNICATION SYSTEM AND METHOD THEREOF AND QAM RECEIVING APPARATUS AND METHOD THEREOF - In a quadrature amplitude modulation (QAM) communication system and corresponding method, and a QAM receiving apparatus and corresponding method, a sending apparatus that generates a sending signal adds CRC bits thereto. In a receiving apparatus, data rate is determined without a 16QAM demapping circuit and/or notification of the data rate, by 64QAM demapping a symbol string based on the received signal using a demapping circuit, independently of whether 16QAM or 64QAM was used on the sent signal. A bit string is thus obtained, and by thinning the bit string responsive to a CRC detection result of a CRC detection circuit, an output signal is provided using a thinning circuit. | 02-26-2009 |
20090067526 | METHOD AND DEVICE FOR TRANSFERRING DATA IN A MULTI-CARRIER SYSTEM HAVING PARALLEL CONCATENATED ENCODING AND MODULATION - The invention relates to a transmitter-receiver pair for improved data transmission in a multi-carrier system and to a corresponding method, according to which a chain coding is used. To this end, a transmitter has a first coding stage, a transmission-demultiplexer stage, a second coding stage, a modulator stage, a transmission multiplexer stage and a multi-carrier modulator, whereby said transmission-demultiplexer stage and the transmission multiplexer stage are controlled by a bit loading device. Similarly, the receiver has a multi-carrier demodulator, a receiver demultiplexer stage, a first decoding stage, a receiver multiplexer stage and a second decoding stage, whereby the receiver multiplexer stage and demultiplexer stage are in turn controlled by the bit loading device. | 03-12-2009 |
20090122890 | OFDM DCM DEMODULATION METHOD - An OFDM DCM demodulation method is provided. The OFDM DCM demodulation method mainly includes the following steps. First, calculate a log likelihood of a first demodulation mode. Then calculate a log likelihood of a second demodulation mode. Finally, calculate a demodulation output according to the log likelihoods of the first demodulation mode and the second demodulation mode. The demodulation output may serve as an output of a demodulator of a receiving end of a DCM communication system. | 05-14-2009 |
20090180565 | SYSTEM FOR, AND METHOD OF, PROCESSING QUADRATURE AMPLITUDE MODULATED SIGNALS - Analog signals encoded with quadrature amplitude modulation (QAM) pass through a coaxial cable at a particular baud rate. These signals have a carrier frequency individual to the TV station being received. They are mixed with signals from a variable frequency oscillator to produce signals at a particular intermediate frequency (IF). An analog-digital converter (ADC) converts the IF signals to corresponding digital signals which are demodulated to produce two digital signals having a quadrature phase relationship. After being filtered and derotated, the digital signals pass to a symmetrical equalizer including a feed forward equalizer (FFE) and a decision feedback equalizer (DFE) connected to the FFE in a feedback relationship. The DFE may include a slicer providing amplitude approximations of increasing sensitivity at progressive times. Additional slicers in the equalizer combine the FFE and DFE outputs to provide the output data without any of the coaxial cable noise or distortions. The equalizer outputs and initially the derotation outputs, and the slicer outputs, servo (1) the oscillator frequency to obtain the IF frequency, (2) the ADC sampling clock to obtain the digital conversion at a rate related to the particular baud rate and (3) the derotator. The servos may have (1) first constants initially after a change in the station selection and (2) second time constants thereafter. The ADC gain is also servoed (1) initially in every ADC conversion and (2) subsequently in every nth ADC conversion where n=integer>1. The above recover the QAM data without any of the coaxial cable noise or distortions. | 07-16-2009 |
20090213953 | Bit Log Likelihood Ratio (LLR) Computation of a 32-QAM System - A method and apparatus for computing and comparing the LLR of a 32-QAM mapping by splitting the mapping point to a most significant bit and four Least Significant Bits. Forming two groups based upon the characteristic of the most significant bit. Use the characteristics of an associated 16-QAM mapping to compute the four Least Significant Bits of the 32-QAM mapping. | 08-27-2009 |
20090220019 | APPARATUS AND METHOD FOR TRANSMITTING DATA USING A PLURALITY OF CARRIERS - A data transmitting and receiving method of transmitting supplementary data in an OFDM communication system is disclosed. The method of transmitting and receiving the OFDM signal includes: mapping an input bit stream into at least one transfer symbol; changing at least one of amplitudes and phases of the transfer symbols that are transmitted by a specific sub-carrier group having a plurality of sub-carriers using constellation modification information to indicate specific additional data; and transmitting the transfer symbols, to which the changing is carried out, to a receiving end by an orthogonal frequency division multiplexing data processing, the constellation modification information being identical to each other with respect to the transfer symbols that are transmitted by the specific sub-carrier group. | 09-03-2009 |
20090245406 | SYSTEM AND METHOD FOR COMMUNICATING DATA USING EFFICIENT FAST FOURIER TRANSFORM (FFT) FOR ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) MODULATION - A communications device includes at least one memory device for storing complex exponential functions as approximations of sine and cosine basis waveforms. A logic circuit adds and subtracts the complex exponential functions to generate an Orthogonal Frequency Division Multiplexed (OFDM) communications signal as a plurality of N data subcarriers that carry communications data. The logic circuit provides efficient and accurate implementation of the IFFT for use as an OFDM modulator using additions of stored complex exponentials and modulation of the integer-valued QAM data symbols using logic shifts and sign changes (2's complement). | 10-01-2009 |
20090245407 | CONSTELLATION REARRANGEMENT FOR TRANSMIT DIVERSITY SCHEMES - A method of transmitting data in a wireless communication system from a transmitter to a receiver, comprising the steps of modulating data at the transmitter using a first signal constellation pattern to obtain a first data symbol. The first data symbol is transmitted to the receiver using a first diversity branch. Further, the data is modulated at the transmitter using a second signal constellation pattern to obtain a second data symbol. Then, the second data symbol is transmitted to the receiver over a second diversity path. Finally, the received first and second data symbol are diversity combined at the receiver. | 10-01-2009 |
20090279629 | MULTIPLE-OUTPUT TRANSMITTER FOR TRANSMITTING A PLURALITY OF SPATIAL STREAMS - A multiple output transmitter is configured for transmitting a single input data stream over two or more spatial channels using OFDM signals. The transmitter includes a commutator to select bits from the single input data stream for two or more bit streams and two or more encoders each to encode bits of one of the bit streams. The commutator operates at a bit rate and sequentially provides the selected bits of the input data stream to the encoders. A spatial bit sequencer selects groups of encoded bits from each of the encoders and assigns individual bits of a selected group at the bit-rate to block permuters in a sequential manner to distribute bits from the selected group across the block permuters. The block permuters produce interleaved blocks of bits for an associated spatial stream. The commutator assigns bits of the input bit stream to more than one encoder to allow each encoder to operate at a lower rate. | 11-12-2009 |
20090323845 | Wireless Mobile Communication System Without Pilot Signals - The present invention is directed to a method for canceling the Doppler shift, multi-path propagation, delays, and long time selective fading influences of phase and/or amplitude modulated signals carried by RF sub-carriers, without requiring pilot signals. The number of m=2 | 12-31-2009 |
20100008438 | SYSTEM AND METHOD FOR BIT ALLOCATION AND INTERLEAVING - A method for transmitting data represented by a plurality of coded bits includes: allocating the coded bits to a plurality of groups; rearranging, for a retransmission of the coded bits, ones of the coded bits allocated to a first one of the plurality of groups to a second one of the plurality of groups, and ones of the coded bits allocated to the second one of the plurality of groups to the first one or a third one of the plurality of groups; and changing, for the retransmission, a sequence of coded bits allocated to each of the plurality of groups after the rearranging. | 01-14-2010 |
20100040163 | CHANNEL CLASSIFICATION AND RATE ADAPTATION FOR SU-MIMO SYSTEMS - A method, apparatus and system are disclosed herein for channel classification and adaptation. In one embodiment, the system comprises a base station having a transmitter that is operable to transmit wireless signals using a plurality of transmission options; and a user terminal having a receiver that is operable to receive and decode wireless signals using a plurality of receiver algorithms, where the user terminal is operable to receive communications from the transmitter over a multiple-input, multiple output (MIMO) channel, to select at least one coding mode to be used by the transmitter on the channel based on rates achievable using MIMO transmission, in view of the channel information, using different combinations of one of the plurality of receiver algorithms and one of the plurality of transmission options, and to send information to identify the at least one coding mode to the base station using a feedback channel, each coding mode specifying at least an encoder to be used by the transmitter for the channel. | 02-18-2010 |
20100061475 | RE-TRANSMISSION IN A MIMO COMMUNICATION SYSTEM - A method for re-transmission in a multiple-input multiple-output (MIMO) communication system, the method comprising: performing spatial mapping of one or more retransmitted data streams and one or more newly transmitted data streams, wherein the spatial mapping comprises switching bits between the re-transmission data streams and the new transmission data streams. | 03-11-2010 |
20100067595 | Wi-Fi, GPS and MIMO Systems - Video and data cross-correlated in-phase and quadrature-phase processed and filtered baseband signals and location finder signals are quadrature modulated and transmitted in systems having two or more than two antennas. Signals used in Wi-Fi networks using Orthogonal Frequency Division Multiplexed (OFDM) modulated signals are also transmitted in the two or more than two antenna transmit system. Data and OFDM signal is used in a Voice over Internet Protocol (VoIP) or Video over Internet Protocol (ViIP) network and video cross-correlated modulated signal is used in ViIP wireless networks and in cellular systems. | 03-18-2010 |
20100098182 | Method and/or OFDM device for SC-FDMA data transmission - In a method and/or an OFDM device for SC-FDMA data transmission, a sequence of input data is transformed by means of a discrete transformation as transformed data signals of coded and modulated data signals on first frequency channels into a first frequency space over a first number of frequencies. The transformed data signals are mapped on second frequency channels in a second frequency space with a larger second number of frequencies. The transformed data signals on the second frequency channels are inverse-transformed using an inverse transformation. Data inversely transformed in such a way are provided for transmission. The transformed data signals are mapped into a frequency range of the second frequency channels in such a way that a constant component of the transformed data signals is mapped centrally within the frequency range. | 04-22-2010 |
20100177835 | Method For Transmitting And Receiving Quadrature Amplitude Modulation Signals, A System For Carrying Out Said Method, A Machine-Readable Carrier And The Use Of A Method For Synchronously Receiving Quadrature Amplitude Modulation Signals - The invention relates to signal transmission. The use of the invention for transmitting and receiving quadrature amplitude modulation signals on unlicensed frequency bands makes it possible to lower a demodulation threshold owing to a low synchronisation threshold. The inventive method consists in extending a burst of M m-level quadrature amplitude modulation signals with the aid of two pseudo-random sequences, one of which is periodically inverted in some bursts, thereby making it possible to extract, on a receiving side, the quadrature amplitude modulation signal components corresponding to a meander signal of the pseudo-random sequence inversion (the frequency of which is known). The inventive method is carried out by means of a corresponding system in a hardware and software mode. Moreover, said method can be used for synchronising the reception of quadrature amplitude modulation signals. | 07-15-2010 |
20100220799 | APPARATUS AND METHOD FOR TRANSMITTING/RECEIVING DATA IN A WIRELESS COMMUNICATION SYSTEM - The present invention discloses a transmission method and apparatus for a wireless communication system. The data transmission method comprises the following steps. A first data mapped in a QAM constellation pattern is transmitted in a first transmission. And a second data, which is reversion of the first data and mapped in said QAM constellation pattern, is retransmitted. In embodiment, the interleaved data is partially swapped based on a predetermined swapping pattern. In another embodiment, first interleaved data and second interleaved data are multiplexed per N bits, N is an integer larger than 1. Therefore, improvement of reliability at first transmission or retransmission in a wireless communication system can be achieved. | 09-02-2010 |
20100232530 | COMMUNICATION APPARATUS - A communication apparatus includes a transmitter for transmitting an outgoing radio signal, a receiver for receiving an incoming radio signal, and a controller for controlling a direct current carrier leakage, and the transmitter includes a first multiplier for multiplying a first carrier-wave signal by an In-phase signal, a second multiplier for multiplying a signal having the similar frequency as and a phase shifted by 90 degree with respect to the first carrier-wave signal by a Quadrature-phase signal, and a transmitting amplifier for amplifying a composite signal multiplied by the In-phase signal and the Quadrature-phase signal, respectively, and outputting the composite signal for forming the outgoing radio signal. | 09-16-2010 |
20100239038 | METHOD AND SYSTEM TO REDUCE PAPR IN SINGLE CARRIER AND SCBT COMMUNICATIONS SYSTEMS - The system ( | 09-23-2010 |
20100266059 | RADIO COMMUNICATION APPARATUS CAPABLE OF SWITCHING MODULATION SCHEMES - A radio communication apparatus that is capable of switching modulation schemes. The radio communication apparatus includes a QPSK modulation signal generator, a QAM modulation signal generator, a transmission radio, and a common transmission power amplifier. The QPSK modulation signal generator modulates transmission data by a QPSK modulation scheme and outputs a QPSK modulation signal. The QAM modulation signal generator modulates transmission data by a QAM scheme and outputs a QAM modulation signal. The transmission radio receives the QPSK modulation signal or the QAM modulation signal and outputs a transmission signal, which is amplified by the common transmission power amplifier. The QPSK modulation signal generator and the QAM modulation signal generator each output signal component that make an average transmission power of the QAM modulation signal in the common transmission power amplifier smaller than an average transmission power of the QPSK modulation signal in the common transmission power amplifier. | 10-21-2010 |
20100284482 | METHOD AND APPARATUS FOR RADIO RESOURCE ALLOCATION IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING COMMUNICATION SYSTEM - In an OFDM communication system, wherein a frequency bandwidth is divided into multiple Physical Resource Units (PRUs), a Frequency Partitioning Configuration Module (FPCM) is provided that configures a physical layer for use in multiple coverage areas. The FPCM divides the PRUs into a first group, for frequency selective allocations, and a second group, for frequency diverse allocations. The FPCM subdivides each of the two groups into multiple sets of PRUs, maps the sets of PRUs from the first group to consecutive PRUs allocated for contiguous segment allocation (CS-PRUs), and maps the sets of PRUs from the second group to consecutive PRUs allocated for distributed segment allocation (DS-PRUs). The FPCM permutes the DS-PRUs and allocates the CS-PRUs and the permuted DS-PRUs to at least one frequency partition. | 11-11-2010 |
20100296597 | Method of Data Modulation Adapted to Selected Modulation Rotational Angle - In a method, modulator, transmitter and receiver, the modulator of data signals to be transmitted simultaneously to at least two receiving mobile stations in the same transmission time slot is adapted to select rotational angle of a QPSK transmission modulation, such as a hybrid α-QPSK modulation used to modulate the data signals to the at least two mobile stations in response to the capabilities of the mobile stations that share the same transmission slot. | 11-25-2010 |
20110002408 | METHOD OF TRANSMITTING MULTI-CARRIER SIGNALS IN A MULTI-ANTENNA SYSTEM - The present invention relates to a method of transmitting a multi-carrier signal intended to be used by a system with Nt transmit antennas, where Nt is greater than or equal to two, and Nr receive antennas, where Nr is greater than or equal to one, of the type using OFDM/OQAM modulation and distributing symbols before transmission in a time-frequency plane, in which method the symbols are distributed over blocks of particular size n | 01-06-2011 |
20110026628 | APPARATUS AND METHOD FOR MAPPING SYMBOL - In a symbol mapping method, transmission data is encoded to generate information bits and redundancy bits. An average LLR value of bits on which the information bits are mapped is different from an average LLR value of bits on which the redundancy bits are mapped. | 02-03-2011 |
20110033003 | GENERALIZED FREQUENCY MODULATION - A receiver may comprise a complex mixer for converting the modulated signal to a complex modulated signal comprising a first in-phase component and a first quadrature component. The receiver may further comprise a digital demodulator. The digital demodulator may comprise at least one processor circuit programmed for applying a phase differencer for generating an output function in terms of a phase difference of the complex modulated signal. Applying the phase differencer may comprise converting the first in-phase component to a function of a phase difference of the first in-phase component expressed in digital time, and converting the first quadrature component to a function of the phase difference of the first quadrature component expressed in digital time. The at least one processor circuit of the digital demodulator may also be programmed for applying a four quadrant inverse tangent to the output function to generate the information signal. | 02-10-2011 |
20110033004 | DUAL CARRIER MODULATION PRECODING | 02-10-2011 |
20110051830 | METHODS AND RECEIVERS OF CARRIER FREQUENCY OFFSET DETECTION - A receiver used for an orthogonal frequency-division multiplexing (OFDM) system is provided. A signal processing device receives an OFDM symbol and processes the OFDM symbol according to the OFDM symbol and a carrier frequency offset compensation coefficient to generate a processed signal. The OFDM symbol includes pilots which have been hierarchically modulated and the processed signal includes the processed pilots. A signal analysis device collects the processed pilots of the processed signal and detects carrier frequency offset to generate the carrier frequency offset compensation coefficient to the signal processing device according to the processed pilots and a plurality of target decision bit error rates. A channel detection module detects a channel response of the processed signal according to the processed pilots and compensates the processed signal to generate an output data. | 03-03-2011 |
20110069772 | TRANSMISSION OF MULTICAST BROADCAST SERVICE (MBS) TRAFFIC IN A WIRELESS ENVIRONMENT - Multicast broadcast service (MBS) transmission in a multiple-input-multiple-output (MIMO) communication being transmitted using one of three modes, a single-layer mode, a spatial multiplexing (SM) mode and a hierarchical mode. In the hierarchical mode, lower quality data is transmitted over a first MIMO layer and enhancement data is transmitted over a second MIMO layer. A receiving device may only successfully receive the lower quality data or may successfully receive the enhancement data to enhance it with. The transmission scheme used, including the mode used, may be selectable, and may be selected based on feedback. | 03-24-2011 |
20110075751 | METHOD OF CODIFICATION AND DECODIFICATION WITH AT LEAST TWO PAIRS OF ORTHOGONAL SEQUENCES - The invention relates to an improved encoding and decoding method with at least two pairs of orthogonal sequences for improving the time necessary for calculating the coefficients of the filter for the purpose of reducing the data overload in communication systems by half by means of the emission of both sequences simultaneously and the emission of the result by means of quadrature modulation to a transmission medium. | 03-31-2011 |
20110085613 | MAPPING METHOD AND DEVICE FOR DISCONTINUOUS TRANSMISSION BITS - A modulation mapping method and device for Discontinuous Transmission (DTX) bits are provided. The method includes: receiving binary symbols from a downlink physical channel; replacing symbol values of DTX bits in the binary symbols with symbol values of non-DTX bits, to obtained updated binary symbols; and performing modulation mapping on the updated binary symbols. Using the DTX bits to replicate the non-DTX bits, the DTX bits are supplied to a receiving end as redundant information of the non-DTX bits, such that the performance for demodulating the non-DTX bits by the receiving end is improved. In addition, when the binary symbols on one branch are all DTX bits, modulation mapping is performed on the binary symbols on the same branch and then a real value 0 is output. That is, when the input symbols on only one branch are all DTX bits, the transmission channel for this branch may be closed down alone, and thus the system transmission power is lowered. | 04-14-2011 |
20110103502 | METHODS FOR DIGITAL SIGNAL PROCESSING AND TRANSMISSION/RECEPTION SYSTEMS UTILIZING SAID METHODS - Methods for digital signal processing and transmission/reception systems utilizing the methods based on the use of LDPC codes, for example a LDPC code with a 3/5 code rate, in combination with a QAM modulation, for example the 16QAM or 64QAM or 256QAM modulation. In transmission, a bit permutation (Demux) is carried out prior to the QAM constellation mapping function, and in reception, the bit permutation is carried out after the QAM constellation demapping function. | 05-05-2011 |
20110110449 | RECEIVER TERMINAL DRIVEN JOINT ENCODER AND DECODER MODE ADAPTATION FOR SU-MIMO SYSTEMS - A system, a method and an apparatus are disclosed herein for receiver terminal driven joint encoder and decoder mode adaptation for SU-MIMO transmission. In one embodiment, the system comprises a transmitter that is able to be directed to transmit wireless signals over a multiple-input, multiple output (MIMO) system using any of a plurality of encoding modes; and a user terminal having a receiver comprising a decoding module which has a plurality of decoding modes, each of which can be used to decode communications from the transmitter received over a multiple-input, multiple output (MIMO) channel, wherein at least one encoding mode is operable with multiple of the decoding modes. The system also comprises a joint selection module that is operable to select for the MIMO transmission the decoding mode from the plurality of decoding modes and an encoding mode from the plurality of encoding modes to be used by the transmitter on the channel, the selection being based on receiver-dependent criteria corresponding to the decoding mode associated with the encoding mode and channel information, receiver hardware and state, and application-specific constraints. The joint selection module is operable to send information to identify the encoding mode to the transmitter using a feedback channel. | 05-12-2011 |
20110122960 | Method for Processing Digital Signals, and Transmission/Reception System Implementing Said Method - The present invention relates to a method for processing digital signals and to a transmission/reception system implementing said method; the present invention is based on the use of LDPC codes, in particular the LDPC code of the DVB-S2 standard, in combination with a QAM modulation, in particular the 1024QAM and 4096QAM modulations; in transmission, a bit permutation (Demux) is carried out prior to the QAM constellation mapping function; in reception, the bit permutation is carried out after the QAM constellation demapping function. | 05-26-2011 |
20110142152 | MULTICARRIER DIGITAL SIGNAL TRANSMISSION SYSTEM USING FILTER BANKS AND MEMORY PRELOADING FOR INITIALIZATION - A transmission system includes an emitter ( | 06-16-2011 |
20110164698 | Systems and methods with non symmetric OFDM modulation - Non-symmetric OFDM system may employ different spectrum bandwidths, different FFT sizes, different cyclic prefixes, different symbol duration and different modulation schemes in two ends of the communication. The transmission spectrum can be one contiguous piece or multiple disjoint pieces by modulating zeros to those subcarriers nearby the spectrum boundaries. Transmitter and receiver maybe designed separately and integrated together via a control module to form a transceiver. | 07-07-2011 |
20110222618 | Method and Apparatus for Efficient Soft Modulation for Gray-Mapped QAM Symbols - In one aspect, the present invention greatly simplifies soft modulation calculations, in part by exploiting certain properties of Gray-mapped QAM constellations used in modulating symbols of interest. In at least one embodiment, the simplified processing includes performing the soft modulation separately for the real and imaginary parts of each symbol of interest, by using the Gray mapping to decompose each of the real and imaginary parts into binary soft modulations for each bit, and then using a computationally-efficient table lookup to calculate the binary soft modulation. Here, the look-up table comprises pre-computed bit contributions to the complex soft symbol value to be formed for the symbol of interest. | 09-15-2011 |
20110228869 | DESIGN METHODOLOGY AND METHOD AND APPARTUS FOR SIGNALING WITH CAPACITY OPTIMIZED CONSTELLATIONS - Communication systems are described that use geometrically shaped constellations that have increased capacity compared to conventional constellations operating within a similar SNR band. In several embodiments, the geometrically shaped is optimized based upon a capacity measure such as parallel decoding capacity or joint capacity. In many embodiments, a capacity optimized geometrically shaped constellation can be used to replace a conventional constellation as part of a firmware upgrade to transmitters and receivers within a communication system. In a number of embodiments, the geometrically shaped constellation is optimized for an Additive White Gaussian Noise channel or a fading channel. In numerous embodiments, the communication uses adaptive rate encoding and the location of points within the geometrically shaped constellation changes as the code rate changes. One embodiment of the invention includes a transmitter configured to transmit signals to a receiver via a communication channel, wherein the transmitter, includes a coder configured to receive user bits and output encoded bits at an expanded output encoded bit rate, a mapper configured to map encoded bits to symbols in a symbol constellation, a modulator configured to generate a signal for transmission via the communication channel using symbols generated by the mapper. In addition, the receiver includes a demodulator configured to demodulate the received signal via the communication channel, a demapper configured to estimate likelihoods from the demodulated signal, a decoder that is configured to estimate decoded bits from the likelihoods generated by the demapper. Furthermore, the symbol constellation is a capacity optimized geometrically spaced symbol constellation that provides a given capacity at a reduced signal-to-noise ratio compared to a signal constellation that maximizes d | 09-22-2011 |
20110243266 | METHOD AND SYSTEM FOR REDUCING INTER CARRIER INTERFERENCE FOR OFDM - According to one embodiment, a method of encoding a plurality of orthogonal frequency division multiplexing (OFDM) signals is disclosed. The method includes: modulating the plurality of OFDM signals according to a modulation scheme, wherein the modulated OFDM signals are mapped to a first axis and a second axis perpendicular to the first axis, and correspond to a first constellation having a plurality of points symmetric with respect to the first axis and the second axis; and differentially encoding the plurality of OFDM signals according to a second constellation plurality of points defined by shifting a position of one of the first constellation plurality of points toward an origin located at an intersection of the first axis and the second axis. | 10-06-2011 |
20110255623 | DATA TRANSMISSIONS IN A MOBILE COMMUNICATION SYSTEM EMPLOYING DIVERSITY AND CONSTELLATION REARRANGEMENT OF A 16 QAM SCHEME - The invention relates to methods for transmitting and receiving a data bit stream in a communication system using 16-QAM constellations. Further, an apparatus for performing the methods is provided. To improve the bit-error rate performance of the communication using the 16-QAM constellations the invention suggests the use 16-QAM constellations with specially selected mapping rules together with a special constellation rearrangement for creating different versions of the 16-QAM constellations. Further, the data stream is transmitted according to a diversity scheme employing different versions of the 16-QAM constellations obtained adhering the mapping rules and rearrangement rules defined by the invention. | 10-20-2011 |
20110274194 | QAM AND GMSK SYSTEMS - Transmit baseband filter and modulator for filtering and modulating a first bit rate signal into a Gaussian filtered modulated signal and a second transmit filter and modulator for filtering and modulating a second bit rate signal into a Quadrature Amplitude Modulated (QAM) signal. A first amplifier and first transmitter for nonlinearly amplifying and a second amplifier and second transmitter for linearly amplifying modulated signals. A diversity receiver and demodulator system for receiving and demodulating transmitted modulated signals. Processor, transmit baseband filter and modulator provides cross-correlated in-phase and quadrature-phase Gaussian filtered Gaussian Minimum Shift Keying (GMSK) modulated signal, spread spectrum Quadrature Phase Shift Keying (QPSK) modulated signal. Transmit processor and filter provides time division multiplexed (TDM) Gaussian filtered baseband signal and Orthogonal Frequency Division Multiplexed (OFDM) in-phase and quadrature-phase baseband modulated signal to a cellular network and to separate wireless network. Diversity receiver and demodulator provides demodulated cross-correlated in-phase and quadrature-phase filtered signal, with receive filter mis-matched to transmit filter. | 11-10-2011 |
20110274195 | CONSTELLATION REARRANGEMENT FOR TRANSMIT DIVERSITY SCHEMES - A method of transmitting data in a wireless communication system from a transmitter to a receiver, comprising the steps of modulating data at the transmitter using a first signal constellation pattern to obtain a first data symbol. The first data symbol is transmitted to the receiver using a first diversity branch. Further, the data is modulated at the transmitter using a second signal constellation pattern to obtain a second data symbol. Then, the second data symbol is transmitted to the receiver over a second diversity path. Finally, the received first and second data symbol are diversity combined at the receiver. | 11-10-2011 |
20110274196 | METHOD AND SYSTEM FOR CODEBOOK DESIGN OF MIMO PRE-CODERS WITH FINITE RATE CHANNEL STATE INFORMATION FEEDBACK - Channel state information in a multiple-input multiple-output (MIMO) pre-coding system is quantized onto a codebook, which comprises one or more unitary matrices, using a cost function. Voronoi regions are computed from the codebook. The codebook may be updated based on the computed Voronoi regions. The channel state information may comprise a matrix V. The cost function f(A) is defined by the following relationship: | 11-10-2011 |
20120039410 | QAM and GMSK Modulation Methods - Filtering and modulating a first bit rate signal into a Gaussian filtered Gaussian Minimum Shift Keyed (GMSK) modulated signal and a second bit rate signal into a Quadrature Amplitude Modulated (QAM) signal. A method for nonlinearly and linearly amplifying GMSK and QAM signals. A diversity receiver and demodulator method for receiving and demodulating transmitted modulated signals. Processing, transmit baseband filtering and modulating signals for providing cross-correlated in-phase and quadrature-phase Gaussian filtered Gaussian Minimum Shift Keying (GMSK) and other cross-correlated modulated signals and spread spectrum Quadrature Phase Shift Keying (QPSK) modulated signals. Transmit processing and filtering for providing time division multiplexed (TDM) Gaussian filtered baseband signal and Orthogonal Frequency Division Multiplexed (OFDM) in-phase and quadrature-phase baseband modulated signal to a cellular network and to separate wireless network. Diversity receiver and demodulator method with multiple antennas for providing demodulated cross-correlated in-phase and quadrature-phase filtered signals. | 02-16-2012 |
20120076224 | Ultra-high-bandwidth low-power-consumption wireless communication systems - An ultra-high-bandwidth low-power-consumption wireless communication system includes (i) a Radio Frequency Integrated Circuit (RFIC) comprising a radio transmitter, transmitting millimeter-wave signals. The radio transmitter includes a Power Amplifier (PA) outputting the millimeter-wave signals at a low power level of between −10 dBm and 20 dBm, and by that allowing inclusion of the PA in the RFIC. The radio transmitter further includes a Voltage Controlled Oscillator (VCO) and a synthesizer driving a mixer up-converting signals into the millimeter-wave signals. The VCO and synthesizer have a combined phase noise between a first level and a second level, wherein the first level is high enough to allow inclusion of the VCO and synthesizer in the RFIC, and the second level is low enough to facilitate transmitting at 16-levels Quadrature-Amplitude-Modulation (16QAM). | 03-29-2012 |
20120076225 | METHOD, APPARATUS AND SYSTEM FOR TRANSMITTING INFORMATION BITS - A method, an apparatus and a system for transmitting information bits are provided. The method for transmitting information bits includes: dividing the information bits to be transmitted into at least two groups; encoding the information bits to be transmitted in each group; modulating the coded bits obtained by the encoding to obtain modulation symbols, in which each modulation symbol is obtained by the modulation of the coded bits in the same group; and mapping and transmitting the modulation symbols. In this way, the receiving end easily reduces the algorithm complexity, thereby ensuring the performance of the receiving end. | 03-29-2012 |
20120093248 | APPARATUS AND METHOD FOR TRANSMITTING DATA USING A PLURALITY OF CARRIERS - A data transmitting and receiving method of transmitting supplementary data in an OFDM communication system is disclosed. The method of transmitting and receiving the OFDM signal includes: mapping an input bit stream into at least one transfer symbol; changing at least one of amplitudes and phases of the transfer symbols that are transmitted by a specific sub-carrier group having a plurality of sub-carriers using constellation modification information to indicate specific additional data; and transmitting the transfer symbols, to which the changing is carried out, to a receiving end by an orthogonal frequency division multiplexing data processing, the constellation modification information being identical to each other with respect to the transfer symbols that are transmitted by the specific sub-carrier group. | 04-19-2012 |
20120099667 | Transmitting high rate data within a MIMO WLAN - A method for transmitting high rate data within a multiple input multiple output (MIMO) wireless local area network (WLAN) begins by determining a data transmission rate. The method continues by, when the data transmission rate is between a first data rate and a second data rate, enabling two transmission paths. The method continues by, for each of the two transmission paths, determining at least one of: level of constellation, number of data subcarriers, rate code, and cyclic prefix duration. | 04-26-2012 |
20120106666 | METHOD FOR DEFINING A SEARCH SEQUENCE FOR SOFT-DECISION SPHERE DECODING ALGORITHM - A low complexity method for determining a search sequence of nodes for an efficient soft-decision sphere decoding algorithm for use in receivers for quadrature amplitude modulation (QAM) communication signals is achieved by determining a first member of the search sequence by rounding a received symbol (z) to a first constellation symbol (x | 05-03-2012 |
20120114055 | RECEIVING APPARATUS AND METHOD FOR PROVIDING INPUT BITS OF FAST FOURIER TRANSFORMER ACCORDING TO MODULATION - A technology is provided capable of improving the efficiency of an OFDM system by obtaining the performance in Bit Error Rate (BER) in a wireless communication using OFDM and determining the minimum FFT input bit that produces a SNR difference of 0.1 dB or below with respect to a theoretical BER graph at a desired performance. | 05-10-2012 |
20120121030 | Compressive Wireless Modulation - A projection code is applied to encode symbols as weighted arithmetic sums of approximately random subsets of binary source bits. Pairs of the symbols are combined to form constellation points, which are sequentially mapped through a constellation to modulate a data signal. | 05-17-2012 |
20120170673 | DIGITAL MODULATION JITTER COMPENSATION FOR POLAR TRANSMITTER - This disclosure is directed towards techniques and methods of suppressing the effect of modulated clock jitter in a digital to analog conversion (DAC) circuit of a polar modulator in a transceiver. A phase locked loop (PLL) in a modulator circuit may introduce a deterministic jitter in DAC generated pulses which may lead to amplitude variations in the DAC generated pulses. The clock jitter may change the duty cycle of the input amplitude to the DAC which may result in a variation of the output of the DAC generated pulse. A digital pre-distortion or digital multiplier circuit may be introduced before the DAC circuit to increase or decrease the DAC amplitude to compensate for the pulse width modulation. | 07-05-2012 |
20120219080 | QUADRATURE DEMODULATION WITH PHASE SHIFT - A quadrature demodulator preweights an input signal prior to mixing with in-phase and quadrature clock signals. In an implementation with discrete phase rotation, a series of weighting circuits may be arranged before or after a select circuit to select the amount of phase rotation. Various implementations may include ratioed current mirrors to perform the weighting function, a stacked arrangement of mixers, an H-bridge input stage, integrated mixers and select circuits, and/or selectable gain stages such as gm cells to perform the weighting function. | 08-30-2012 |
20120263251 | GENERALIZED OFDM (GOFDM) FOR ULTRA-HIGH-SPEED SERIAL OPTICAL TRANSPORT NETWORKS - A coded multidimensional modulation system called generalized OFDM (GOFDM) uses orthogonal subcarriers as bases functions, and the signal constellation points of corresponding multidimensional constellation diagram are obtained as N-dimensional Cartesian product of one-dimensional PAM/two-dimensional QAM. In GOFDM, the N-dimensional/2N-dimensional signal constellation point is transmitted over all N subcarriers/2N-subcarriers, which serve as individual bases functions. Even if some of the subcarriers are severely affected by channel distortion, the overall signal constellation point will face only small distortion, when strong channel capacity achieving channel codes are used. In addition, because the channel capacity is a linear function of number of dimensions, the spectral efficiency of optical transmission systems is significantly improved. Finally, since Euclidean distance of multidimensional signal constellation is much larger that that of two-dimensional signal constellations, OSNR sensitivity is dramatically improved. | 10-18-2012 |
20120294381 | Multi-User Multiple Input Multiple Output Wireless Communications - A method implemented in a user equipment used in a multi-user multiple input multiple output (MU-MIMO) wireless communications system is disclosed. The method includes receiving from a base station an indication of a first modulation type for the user equipment, receiving a first data signal for the user equipment, receiving a second data signal for a co-scheduled user equipment, where a second modulation type for the co-scheduled user equipment is unknown to the user equipment, and deciding the second modulation type. Other methods, systems, and apparatuses also are disclosed. | 11-22-2012 |
20120321007 | QAM CDMA and TDMA Communication Methods - Filtering and modulating a first rate data signal into a Quadrature Amplitude Modulated (QAM) Code Division Multiple Access (CDMA) and a second rate data signal into a Time Division Multiple Access (TDMA) modulated signal and selecting between the transmission of the CDMA and TDMA modulated signals. A method for nonlinearly and linearly amplifying TDMA and CDMA signals. A diversity receiver and demodulator method for receiving and demodulating transmitted modulated signals. Processing, transmit baseband filtering and modulating signals for providing cross-correlated in-phase and quadrature-phase Gaussian filtered Gaussian Minimum Shift Keying (GMSK) and other cross-correlated modulated signals and spread spectrum Quadrature Phase Shift Keying (QPSK) modulated signals. Transmit processing and filtering for providing time division multiplexed (TDM) Gaussian filtered baseband signal and Orthogonal Frequency Division Multiplexed (OFDM) in-phase and quadrature-phase baseband modulated signal to a cellular network and to separate wireless network. | 12-20-2012 |
20130010883 | Data Re-transferring Method Based on Bit Transformation - A data re-transferring method is based on bit transformation in a communication system. The communication system adopts a high order modulation and supports a re-transferring mechanism. The method includes transforming bits of data to be retransferred in a symbol according to a selected transformation mode, mapping the transformed bits to one constellation figure, and performing Quadrature Amplitude Modulation for the mapped bits. | 01-10-2013 |
20130039436 | TECHNIQUES FOR DETECTION OF SIGNALS IN MULTIPLE-INPUT MULTIPLE-OUTPUT COMMUNICATION SYSTEMS - A receiver of a multiple-input multiple-output (MIMO) system performs QR decomposition of the channel matrix to enable detection of a transmitted vector in a layered manner. In each layer, a sub-vector of the transmitted vector is estimated. A reactive tabu search is performed if an estimated symbol differs from a nearest symbol in the alphabet by a predetermined value. The receiver may order the entries of the channel matrix prior to QR decomposition to enable estimation in an optimum order. In another embodiment, a receiver performs multiple reactive tabu searches to estimate a transmitted vector. The receiver employs a fixed threshold or a variable threshold for a cost function used in the multiple reactive tabu searches depending on whether the MIMO system is under-determined or not. The techniques enable low bit-error rate (BER) performance in MIMO systems with large number of antennas and when higher-order modulation techniques are used. | 02-14-2013 |
20130083862 | Design Methodology and Method and Apparatus for Signaling with Capacity Optimized Constellations - Communication systems are described that use geometrically shaped constellations that have increased capacity compared to conventional constellations operating within a similar SNR band. In several embodiments, the geometrically shaped is optimized based upon a capacity measure such as parallel decoding capacity or joint capacity. In many embodiments, a capacity optimized geometrically shaped constellation can be used to replace a conventional constellation as part of a firmware upgrade to transmitters and receivers within a communication system. In a number of embodiments, the geometrically shaped constellation is optimized for an Additive White Gaussian Noise channel or a fading channel. In numerous embodiments, the communication uses adaptive rate encoding and the location of points within the geometrically shaped constellation changes as the code rate changes. | 04-04-2013 |
20130177093 | APPARATUS AND METHOD FOR TRANSMITTING DATA USING A PLURALITY OF CARRIERS - An apparatus for receiving signals includes a receiver for receiving a time domain signal from a transmitter, wherein at least one first information bit is mapped, resulting in at least one first mapped symbol; at least one second information bit is mapped, resulting in at least one second mapped symbol; the at least one second mapped symbol is multiplied by at least one third information bit; and the time domain signal is generated from the at least one first mapped symbol and the at least one second mapped symbol. | 07-11-2013 |
20130215985 | METHOD FOR PERFORMING AN ADAPTIVE MODULATION AND CODING SCHEME IN MOBILE COMMUNICATION SYSTEM - A method for performing an adaptive modulation and coding scheme in a mobile communication system. Including receiving a signal and selecting a modulation and coding scheme (MCS) level from an MCS subset of an MCS set considering information derived from the signal, by a mobile station. The MCS subset is selected in accordance with a service type related to the mobile station and the MCS subset is configured with one or more MCS levels, the MCS set is represented by 5 bits and the MCS subset is represented by 4 bits to indicate MCS value, respectively, and the 4 bits of the MCS subset is a part of the 5 bits of the MCS set. | 08-22-2013 |
20130215986 | Blind Estimation of Frequency and Phase Offsets for Received Signals - A mechanism for jointly correcting carrier phase and carrier frequency errors in a demodulated signal. A computer system may receive samples of a baseband input signal (resulting from QAM demodulation). The computer system may compute values of a cost function J over a grid in a 2D angle-frequency space. A cost function value J(θ,ω) is computed for each point (θ,ω) in the grid by (a) applying a phase adjustment of angle θ and a frequency adjustment of frequency ω to the input signal; (b) performing one or more iterations of the K-means algorithm on the samples of the adjusted signal; (c) generated a sum on each K-means cluster; and (d) adding the sums. The point (θ | 08-22-2013 |
20130223550 | DISCRETE MULTI-TONE SYSTEMS FOR HALF-DUPLEX IP LINKS - A DMT system for a half-duplex two-way link carries Internet protocol encoded video stream on a coaxial cable that also carries a baseband rendition of the same video stream. A plurality of downlink symbols modulated on a subband of subcarriers in a downlink signal are decoded. The symbols may carry data encoded on a subband using a constellation of QAM symbols assigned to the subband. Other subbands may be associated with different QAM constellations. Lower-order constellations of QAM symbols may be assigned to subbands that include higher-frequency subcarriers and higher-order constellations of QAM symbols may be assigned to subbands that include lower-frequency subcarriers. A block error correction decoder may be synchronized based on an identification of the first constellation of QAM symbols and information identifying boundaries between the plurality of downlink symbols. | 08-29-2013 |
20130259148 | AMPLITUDE ENHANCED FREQUENCY MODULATION - Methods and systems for transmitting a spectrally efficient signal. The method includes frequency modulating an input signal in a transmitter to generate a first frequency modulated (FM) signal and generating in the transmitter an amplitude modulated (AM) component based at least on the input signal. The method may then include generating a second FM signal based at least on the AM component and the first FM signal and sending the second FM signal to a receiver. | 10-03-2013 |
20130329819 | Method, Radio Unit and Radio Base Station for Adjusting Thresholds for Crest Factor Reduction - The present invention relates to clipping thresholds adjustment for Crest Factor Reduction CFR in a radio unit, wherein the radio unit comprises one or more clipping stages that apply respective clipping thresholds to clip input signals, comprising: determining a target threshold for the clipping stages based on a target PAR and the amplitudes or powers of the input signals, estimating the direction in which original PAR of the input signals changes by comparing amplitudes of the clipped signals from the clipping stages with the target threshold, and adjusting the clipping thresholds based on the estimated direction. The present invention also relates to dynamic stage control. With the present invention, clipping thresholds and clipping stages are adaptively changes with dynamic original PAR of input signals and the efficiency of power amplifier is increased with a low implementation cost. | 12-12-2013 |
20140029682 | LOW-IF TRANSCEIVER ARCHITECTURE - A transceiver, receiver, and transmitter are provided. The transceiver may also include a programmable matching block configured to implement impedance-matching between an antenna and the receiver and/or between the antenna and the transmitter. The programmable matching block may implement the impedance-matching through a shared matching circuit block. The programmable matching block may include at least one of a programmable inductor and a programmable capacitor. | 01-30-2014 |
20140133591 | MULTIPLE INPUT MULTIPLE OUTPUT (MIMO) TRANSMITTED SIGNAL VECTOR ESTIMATION EMPLOYING MONTE CARLO SAMPLING TECHNIQUES - A method of determining a transmitted vector (x) in a MIMO receiver includes the steps of receiving a received vector (y) representative of the transmitted vector (x), generating a first random number and forming, in a first iteration, a first symbol of a first candidate vector, the candidate vector representing a potential solution vector. The step of forming is based on a first approach if the first random number is greater than a first predetermined value (q), but is based on a second approach if the random number is less than or equal to the first predetermined value (q). The first approach randomly selects the first symbol from a uniform distribution of symbols in the transmission alphabet. The second approach selects the first symbol based on Gibbs sampling. The method represents a randomized Markov Chain Monte Carlo (RMCMC) sampling technique. | 05-15-2014 |
20140133592 | APPARATUS FOR TRANSMITTING AND RECEIVING A SIGNAL AND METHOD OF TRANSMITTING AND RECEIVING A SIGNAL - According to one embodiment, a method of transmitting at least one broadcasting signal having PLP (Physical Layer Pipe) data and preamble data includes: encoding the PLP data; encoding the preamble data; mapping the encoded PLP data to PLP data symbols by QAM (Quadrature Amplitude Modulation) modulations; mapping the encoded preamble data to preamble data symbols by QAM modulations; building a signal frame including the PLP data symbols and the preamble data symbols, wherein the preamble data symbols include first signaling information and second signaling information, wherein the first signaling information is for the second signaling information and includes size information of the second signaling information, and wherein the second signaling information is for the PLP data symbols; modulating the signal frame by an Orthogonal Frequency Division Multiplexing (OFDM) method; and transmitting the modulated signal frame. | 05-15-2014 |
20140198867 | Communication System Having Cross Polarization Interference Cancellation (XPIC) - An all outdoor unit communication system, for performing cross polarization interference cancellation, is provided. The system includes a first outdoor unit (ODU) configured to receive a horizontally polarized signal, a first RF module configured to convert the horizontally polarized signal into a first in-phase (I) component and a first quadrature (Q) component, and a first modem configured to up-convert the first I and Q components from baseband into a horizontally polarized intermediate frequency (IF) signal. The system also includes a second ODU configured to receive a vertically polarized signal, a second RF module configured to convert the vertically polarized signal into a second I component and a second Q component, and a second modem configured to up-convert the second I and Q components from baseband into a vertically polarized IF signal. The system is configured to share, via an interconnect, the polarized IF signals between the first and second ODUs. | 07-17-2014 |
20140233664 | System and Method for Orthogonal Frequency Division Multiplexing-Offset Quadrature Amplitude Modulation - A method for performing orthogonal frequency division multiplexing (OFDM)/offset quantization amplitude modulation (OQAM) includes obtaining a data burst. The method includes performing weighted circularly convolved filtering modulation on the data burst to produce an output signal. The method further includes a first wireless device transmitting the output signal to a second wireless device. The second wireless device receives an input signal from the first wireless device, and the second wireless devices performs weighted circularly convolved demodulation filtering on the input signal to produce the data burst. | 08-21-2014 |
20140254698 | SOFTWARE DEFINED RADIO - A software defined radio is disclosed. The software defined radio may utilize a method for encoding a bit stream into non-periodic spiral-based symbol waveforms for transmission and reception. The method includes transmitting a signal constructed from one or more non-periodic modulation sets residing on a memory system of the software defined radio, where each modulation set corresponds to a symbol alphabet and provides non-periodic symbol waveforms corresponding to symbol bit sequences segmented by a microprocessor according to alphabet size. The method also includes receiving the signal constructed from one or more spiral modulation sets, wherein the signal from one or more spiral modulation sets are filtered and then fed to an analog to digital converter, where the signal constructed from the one or more spiral modulation sets is digitized and are fed to the microprocessor. A non-transitory computer storage media may also execute the method. | 09-11-2014 |
20140269959 | APPARATUS AND METHOD FOR SYMBOL MAPPING IN WIRELESS COMMUNICATION SYSTEM USING MULTI TONE FREQUENCY QUADRATURE AMPLITUDE MODULATION - A method of operating a base station in a wireless communication system supporting Frequency-Quadrature Amplitude Modulation (FQAM) and Multi-Tone FQAM (MT-FQAM) is provided. The method includes determining a modulation scheme of data to be transmitted, and modulating the data according to the determined modulation scheme, wherein if at least one resource block is included in the data and if the at least one resource block is mapped to at least one tone in a distributed manner, the MT-FQAM scheme is selected, or if one resource block is included in the data and if the one resource block is mapped to at least one tone in a continuous manner, the FQAM scheme is selected, or if multiple resource blocks are included in the data and if the multiple resource blocks are mapped to at least one tone in a continuous manner, the MT-FQAM scheme is selected. | 09-18-2014 |
20140269960 | TRANSMITTING METHOD, RECEIVING METHOD, TRANSMITTER AND RECEIVER - D-dimensional vectors that each have D real-valued symbols as elements are converted into D-dimensional rotated vectors that each have D real symbols as elements. The conversion is performed by multiplying each of the D-dimensional vectors by a D×D orthogonal matrix. A complex symbol sequence including N | 09-18-2014 |
20140348252 | METHOD FOR TRANSMITTING AT LEAST ONE MULTI-CARRIER SIGNAL CONSISTING OF OFDM-OQAM SYMBOLS - Disclosed is a transmission method of transmitting at least one multicarrier signal made up of OFDM-OQAM symbols to a receive antenna of a receiver device, the transmission method being for use by a transmitter device having at least one transmit antenna. In one embodiment, the method comprises, for each transmit antenna of the transmitter device, filtering OFDM-OQAM symbols associated with the transmit antenna using a time-reversal prefilter defined from an estimate of the transmission channel between the transmit antenna and the receive antenna and transmitting the filtered OFDM-OQAM symbols via the transmit antenna over the transmission channel. | 11-27-2014 |
20140355701 | SIGNAL DUTY CYCLE REDUCTION - A method may include receiving a positive in-phase (“I”)-channel signal (“I+ signal”), a negative I-channel signal (“I− signal”), a positive quadrature-phase (“Q”)-channel signal (“Q+ signal”), and a negative Q-channel signal (“Q− signal”). The method may further include outputting a truncated I+ signal, a truncated I− signal, a truncated Q+ signal, and a truncated Q− signal. The method may further include generating the truncated I+ signal based on the I+ and Q+ signals and a complement of the truncated Q− signal, generating the truncated I− signal based on the I− and Q− signals and a complement of the truncated Q+ signal, generating the truncated Q+ signal based on the I− and Q+ signals and a complement of the truncated I+ signal, and generating the truncated Q− signal based on the I+ and Q− signals and a complement of the truncated I− signal. | 12-04-2014 |
20140369434 | System and Method for Designing and Using Multidimensional Constellations - A method for generating a codebook includes applying a unitary rotation to a baseline multidimensional constellation to produce a multidimensional mother constellation, wherein the unitary rotation is selected to optimize a distance function of the multidimensional mother constellation, and applying a set of operations to the multidimensional mother constellation to produce a set of constellation points. The method also includes storing the set of constellation points as the codebook of the plurality of codebooks. | 12-18-2014 |
20140376651 | Performing Image Rejection On Bandpass Signals - An image rejection (IR) circuit is configured to receive a complex signal from a radio frequency (RF) mixer, where the complex signal includes an in-phase signal portion and a quadrature signal portion. This IR circuit may include: an in-phase path to remove first mismatch information from the in-phase signal portion and associated with at least one in-phase multi-tap filter; a quadrature path to remove second mismatch information from the quadrature signal portion and associated with at least one quadrature multi-tap filter; and a correlation unit to independently update each of the multiple taps of the in-phase multi-tap filter and the quadrature multi-tap filter according to a priority scheme. | 12-25-2014 |
20150016553 | INFORMATION TRANSMISSION METHOD AND DEVICE - Embodiments of the present invention provide an information transmission method and device. The method includes: reporting, by a UE, a CQI value to an eNB; receiving, by the UE, an MCS value sent by the eNB, where the MCS value is determined by the eNB according to the CQI value; and receiving, by the UE, PDSCH data according to the MCS value, where the CQI value and the MCS value are determined according to a second set of tables, where a modulation scheme that can be supported by the second set of tables is higher than 64QAM. The embodiments of the present invention can improve system performance and reduce waste of feedback resources. | 01-15-2015 |
20150036759 | COFDM Using Pseudo Orthogonal QPSK Coding - A Coded Orthogonal Frequency Division Multiplexing (COFDM) communication systems is implemented in which each subcarrier data stream is individually FEC encoded instead of FEC encoding the overall input data stream as implemented in conventional COFDM systems. Specifically, each subcarrier is independently encoded using pseudo orthogonal QPSK M-QAM FEC modulators, transmitted, and decoded using pseudo orthogonal QPSK M-QAM FEC demodulators. Multiplexers and demultiplexers randomize subcarrier symbols across all subcarriers to prevent contiguous subcarrier data errors due to fading or corruption by narrowband interference. This technology can be applied to many wireless and wired communication systems including wireless underwater RF communications. | 02-05-2015 |
20150117558 | ORTHOGONAL FREQUENCY-DIVISION MULTIPLEXING (OFDM) PEAK TO AVERAGE POWER RATIO (PAPR) REDUCTION USING LOW COMPLEXITY TRANSFORMATIONS - Methods and apparatus are provided for reducing Peak to Average Power Ratio (PAPR) in Orthogonal Frequency-Division Multiplexing (OFDM) modulation. A set of low complexity transformations is applied to an OFDM signal to generate a plurality of differently transformed OFDM signals. One of the plurality of differently transformed OFDM signals having a lowest PAPR is selected. The selected one of the plurality of differently transformed OFDM signals is transmitted. | 04-30-2015 |
20150295740 | COMMUNICATION SYSTEM, RECEIVING DEVICE, AND SEMICONDUCTOR DEVICE - A communication system includes a transmitting device that transmits a signal based on pluralities of symbol coordinates on a constellation and pluralities of trajectory coordinates between respective ones of the pluralities of symbol coordinates, average coordinates of the pluralities of trajectory coordinates being different coordinates from coordinates of origin, and a receiving device that accumulates pluralities of trajectory coordinates between respective ones of the pluralities of symbol coordinates on the constellation in the signal received from the transmitting device, and estimates a phase of the signal received from the transmitting device based on a value representing a difference between average coordinates of the pluralities of trajectory coordinates accumulated and the different coordinates. | 10-15-2015 |
20150295747 | COMMUNICATION SYSTEM, RECEIVING DEVICE, AND SEMICONDUCTOR DEVICE - A communication system includes a transmission device that transmits a signal, based on a plurality of symbol coordinates on a constellation, which characterize a shape having a predetermined rotational asymmetrical shape, and a receiving device that accumulates symbol coordinates on the constellation in the signal received from the transmission device and estimates the phase of the signal received from the transmission device, based on a difference between the direction of a shape characterized by the accumulated symbol coordinates and the direction of the predetermined shape. | 10-15-2015 |
20150312080 | System and Method for Orthogonal Frequency Division Multiplexing-Offset Quadrature Amplitude Modulation - A method for performing orthogonal frequency division multiplexing (OFDM)-offset quantization amplitude modulation (OQAM) includes obtaining a data burst. The method includes performing weighted circularly convolved filtering modulation on the data burst to produce an output signal. The method further includes a first wireless device transmitting the output signal to a second wireless device. The second wireless device receives an input signal from the first wireless device, and the second wireless devices performs weighted circularly convolved demodulation filtering on the input signal to produce the data burst. | 10-29-2015 |
20150326416 | Communication System Having Cross Polarization Interference Cancellation (XPIC) - An all outdoor unit communication system, for performing cross polarization interference cancellation, is provided. The system includes a first outdoor unit (ODU) configured to receive a first directionally polarized signal, a first RF module configured to convert the first directionally polarized signal into a first in-phase (I) component and a first quadrature (Q) component, and a first modem configured to up-convert the first I and Q components from baseband into a first directionally polarized intermediate frequency (IF) signal. The system being configured to communicate, via an interconnect coupled to the first ODU, a second directionally polarized IF signal to the first ODU, and where the first modem is further configured to utilize the second directionally polarized IF signal to cancel out at least a portion of a first cross-polarization leakage at the first ODU. | 11-12-2015 |
20150341144 | TRANSMITTER, RECEIVER, AND SIGNAL PROCESSING METHOD THEREOF - A transmitter, a receiver and signal processing methods are provided. The transmitter includes: an encoder configured to perform encoding on an information word based on a parity check matrix to generate a codeword including a plurality of non-binary symbols; an interleaver configured to interleave the codeword; and as modulator configured to modulate the interleaved codeword to generate a plurality of modulation symbols. The interleaver is configured to interleave the codeword such that the modulator maps a predetermined non-binary symbol from among the plurality of non-binary symbols constituting the codeword to a predetermined position in a modulation symbol among the plurality of modulation symbols. | 11-26-2015 |
20160065403 | METHOD AND APPARATUS FOR ACCOMMODATING HIGHER ORDER MODULATION IN WIRELESS COMMUNICATION - A method and apparatus for reconfiguring a wireless transmit/receive unit (WTRU) are directed to receiving an active set update message indicating that a mode of operation allowing a certain modulation scheme is enabled or disabled and performing at least one of: performing a MAC reset procedure, updating a set of reference enhanced transport format combination indicators (E-TFCIs) and associated power offsets, determining actions related to E-DPCCH boosting, modifying information related to an enhanced dedicated channel (E-DCH), and modifying an index that indicates an E-DCH transport block size table. The update message includes at least one modified information element (IE). | 03-03-2016 |
20160080187 | SYMBOL TRANSMISSION METHOD AND APPARATUS FOR USE IN FILTER BANK MULTICARRIER SYSTEM - The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4th-Generation (4G) communication system such as Long Term Evolution (LTE). | 03-17-2016 |
20160087830 | Multi-Mode Orthogonal Frequency Division Multiplexing Transmitter for Highly-Spectrally-Efficient Communications - A transmitter may comprise a symbol mapper circuit and operate in at least two modes. In a first mode, the number of symbols output by the mapper circuit per orthogonal frequency division multiplexing (OFDM) symbol transmitted by said transmitter may be greater than the number of data-carrying subcarriers used to transmit the OFDM symbol. In a second mode, the number of symbols output by said mapper circuit per orthogonal frequency division multiplexing (OFDM) symbol transmitted by said transmitter is less than or equal to the number of data-carrying subcarriers used to transmit said OFDM symbol. The symbols output by the symbol mapper circuit may be N-QAM symbols. While the circuitry operates in the first mode, the symbols output by the mapper may be converted to physical subcarrier values via filtering and decimation prior to being input to an IFFT circuit. | 03-24-2016 |
20160105302 | METHOD FOR COMMUNICATION VIA THREE ORTHOGONAL WAVEFORMS - Aspects of the present disclosure aim at providing three orthogonal waveforms that can be used for transmitting 3n bits (n bits from each waveform) at a given frequency. Such three orthogonal waveforms can be used in applications such as QAM to create a 3-dimensional QAM, along with use in other like applications such as in Orthogonal frequency-division multiplexing (OFDM), Quadrature Phase Shift Keying (QPSK), Binary Phase Shift Keying (BPSK), among others. In an aspect, a method of the present disclosure includes a step of generating three orthogonal waveforms as cos(θ)+k, cos(θ+2π/3)+k, and cos(θ+4π/3)+k, where k is the DC component and can have a value of 0.5 volts, and θ=2πft with f being the (baseband or passband) frequency=1/T, with T being Time Period, and t being time. Cosine waveforms can be equivalently replaced by sine waveform separated by 120 degrees. | 04-14-2016 |
20160112218 | CHANNEL ESTIMATION DEVICE, RECEIVING DEVICE, CHANNEL ESTIMATION METHOD, CHANNEL ESTIMATION PROGRAM, AND RECORDING MEDIUM - A sum of products calculation of a predetermined tap number of tap data and a prescribed tap number of coefficients is carried out and a sum of the predetermined number of tap data is calculated. A replica signal is calculated on the basis of the sum of products calculation result, the sum of the tap data, and a correction coefficient. A residual signal is calculated as the difference between the replica and received signals. The predetermined tap number of coefficients is updated based on the predetermined tap number of tap data and the residual signal, and the correction coefficient calculated from the residual signal. Here, the tap data is either a data symbol before the superimposition of a DC component or an estimation thereof. This allows an adaptive FIR filter used in channel estimation of a received signal by a digitally modulated wave whereupon a DC component is superimposed. | 04-21-2016 |
20160112237 | METHOD AND DEVICE FOR TRANSMITTING DATA BY USING MULTIDIMENSIONAL CONSTELLATION DIAGRAM - Embodiments of the present invention relate to the field of communications, and provide a method and a device for transmitting data by using a multidimensional constellation diagram, which can further improve bit error rate-signal to noise ratio performance by means of a multidimensional constellation diagram. The method is: First, bit data is mapped, by using an n-dimensional constellation diagram, into a column vector including n real numbers, then the n real numbers included in the column vector are modulated by using a resource element and sent, and after demodulating the n real numbers from a received signal, a receiving device finds, in the n-dimensional constellation diagram, a constellation point with coordinate values having a closest Euclidean distance to a point with coordinates being the n real numbers, and finally maps the coordinate values of the constellation point back into the bit data. | 04-21-2016 |
20160112238 | PARTIAL DISCRETE FOURIER TRANSFORM-SPREAD IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING SYSTEM - A method of transmitting data may include converting a stream of serial data bits into a set of parallel quadrature amplitude modulation (QAM) symbols. The method may additionally include applying a partial discrete Fourier transform-spread technique to transform a block of low-frequency subcarriers into a single-carrier QAM signal. The single-carrier QAM signal may bear information of a first subset of QAM symbols from the set of parallel QAM symbols. The method may additionally include transforming one or more remaining QAM symbols to form one or more subcarriers. Each of the one or more subcarriers may bear information of a corresponding QAM symbol from the one or more remaining QAM symbols. The method may additionally include generating a hybrid signal that includes the single-carrier QAM signal and the one or more subcarriers. The method may additionally include transmitting the hybrid signal. | 04-21-2016 |
20160134460 | DIFFERENTIAL CURRENT MODE LOW LATENCY MODULATION AND DEMODULATION FOR CHIP-TO-CHIP CONNECTION - A chip-to-chip communications circuit which is particularly well-suited for short range communication (less than a few inches) from one integrated circuit (chip) to another is presented. The circuits preferably utilize multi-frequency quadrature amplitude modulation (QAM) mechanisms for converting digital data bits from a parallel form into a serial analog stream for communication over a chip I/O connection. Differential current mode modulation in the transmitter, and demodulation in the receiver, are utilized which reduce latency and power-consumption while increasing manufacturing yields and resilience to process variations. | 05-12-2016 |
20160149746 | PHASE SYNCHRONIZATION OF MODULATION OR DEMODULATION FOR QAM-BASED MULTIBAND TSV-LINK - A chip-to-chip communications circuit which is particularly well-suited for short range wired RF communication from one integrated circuit (chip) to another is presented. The circuits preferably utilize multi-frequency quadrature amplitude modulation (QAM) mechanisms for converting digital data bits from a parallel form into a serial analog stream for communication over a chip I/O connection. During a phase calibration cycle, a phase adjustment controller in the transmitter interoperates with a phase adjustment controller in the receiver, to adjust a phase locked-loop (PLL) circuit to correct for the phase delay arising in response to signal propagation between transmitter and receiver. | 05-26-2016 |
20160182162 | CALIBRATING RF PATH DELAY AND IQ PHASE IMBALANCE FOR POLAR TRANSMIT SYSTEM | 06-23-2016 |
20160204969 | System and Method for Using Semi-Orthogonal Multiple Access in Wireless Local Area Networks | 07-14-2016 |
20170237598 | METHOD AND APPARATUS FOR HIGH-SPEED DATA TRANSFER EMPLOYING SELF-SYNCHRONIZING QUADRATURE AMPLITUDE MODULATION | 08-17-2017 |
20190149385 | TRANSMISSION METHOD, TRANSMISSION DEVICE, RECEPTION METHOD, AND RECEPTION DEVICE | 05-16-2019 |