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Class Information
Number: 375/261
Name: Pulse or digital communications > Systems using alternating or pulsating current > Plural channels for transmission of a single pulse train > Quadrature amplitude modulation
Description: Subject matter in which the transmitted signal can be represented as the superposition of two modulated signals, each being obtained by pulse amplitude modulation of a signal sequence on a sinusoidal carrier, the two signal sequences being generated in synchronization at the same rate, and the two carriers being of the same frequency but 90 degrees apart in phase.

Sub-classes under this class:

Class Number Class Name Patents
375/262 Maximum likelihood decoder or viterbi decoder 1,254
375/264 Multilevel 233
375/263 Partial response 97
375/265 Trellis encoder or trellis decoder 1,077

Patents under this class:

Patent Number Title Of Patent Date Issued
8711904 Calibration method for non-ideal transceivers Apr. 29, 2014
8705668 Calculation of soft values for uplink communication Apr. 22, 2014
8693575 Wireless precoding methods Apr. 8, 2014
8693564 Low overhead feedback scheme for codebook based closed-loop MIMO Apr. 8, 2014
8693559 Method and system for communication Apr. 8, 2014
8687724 Method for accelerating the precoding and pre-decoding of symbols in OFDM systems Apr. 1, 2014
8687678 Parameterized codebook with subset restrictions for use with precoding MIMO transmissions Apr. 1, 2014
8687677 Method for digital wireless communications Apr. 1, 2014
8675762 Method of transforming pre-coded signals for multiple-in-multiple-out wireless communication Mar. 18, 2014
8675754 Hybrid modulation schemes used in data communication Mar. 18, 2014
8670494 Apparatus for transmitting and receiving a signal and method of transmitting and receiving a signal Mar. 11, 2014
8666000 Reduced state sequence estimation with soft decision outputs Mar. 4, 2014
8665977 Multilevel cluster-based MIMO detection method and MIMO detector thereof Mar. 4, 2014
8665126 .SIGMA..DELTA. difference-of-squares LOG-RMS to DC converter with forward and feedback paths signal squaring Mar. 4, 2014
8660208 Apparatus and methods for QAM modulation using dual polar modulation Feb. 25, 2014
8660199 Method of demodulating a quadrature amplitude modulation signal and method of data communication Feb. 25, 2014
8660167 Device and method for distortion-robust decoding Feb. 25, 2014
8659456 Electronic device and transmitter DC offset calibration method thereof Feb. 25, 2014
8655396 Methods and apparatus for power allocation and/or rate selection for UL MIMO/SIMO operations with PAR considerations Feb. 18, 2014
8654892 Multiple transmit antenna interleaver design Feb. 18, 2014
8654867 Transformer power combiner with filter response Feb. 18, 2014
8654689 Advanced signal processors for interference cancellation in baseband receivers Feb. 18, 2014
8649469 Signal reception Feb. 11, 2014
8649429 Systems for reducing adverse effects of deep fades in DTV signals designed for mobile reception Feb. 11, 2014
8644406 Apparatus for transmitting and receiving a signal and method of transmitting and receiving a signal Feb. 4, 2014
8638880 Radio base station and user equipment and methods therein Jan. 28, 2014
8638732 Apparatus and method for allocating resources using codebook in a broadband wireless communication system Jan. 28, 2014
8634490 Techniques for detection of signals in multiple-input multiple-output communication systems Jan. 21, 2014
8634445 Pulse modulation and demodulation in a multiband UWB communication system Jan. 21, 2014
8630371 Channel estimation using linear phase estimation Jan. 14, 2014
8630364 Termination techniques for multi-index continuous phase encoders for wireless networks Jan. 14, 2014
8630363 Single-carrier block transmission with trellis coded modulation (TCM), multi-level coded modulation (MLCM) and bit-interleaved MLCM (BIMLCM) Jan. 14, 2014
8630362 QLM co-state MAP trellis Jan. 14, 2014
8625694 Signal processing for independently produced signals Jan. 7, 2014
8619896 Method, apparatus and system for transmitting information bits Dec. 31, 2013
8619894 Methods and apparatus for beamforming Dec. 31, 2013
8619893 Receiving apparatus and receiving method Dec. 31, 2013
8611833 Adaptive bearer configuration for broadcast/multicast service Dec. 17, 2013
8611475 Channel estimation and symbol boundary detection method Dec. 17, 2013
8611445 Multiple-input multiple-output wireless transceiver architecture Dec. 17, 2013
8611444 Receiver and signal receiving method thereof Dec. 17, 2013
8610514 Full spectrum modulator for digital television signals Dec. 17, 2013
8605837 Adaptive frequency-domain reference noise canceller for multicarrier communications systems Dec. 10, 2013
8605805 Receiver, channel state information compressing method, and computer program Dec. 10, 2013
8599944 Pulse modulation circuit and pulse modulation method Dec. 3, 2013
8599938 Linear and polar dual mode transmitter circuit Dec. 3, 2013
8594219 Transposed structure for cyclic delay diversity (CDD) based precoding Nov. 26, 2013
8594155 Multi-carrier transmitter design on adjacent carriers in a single frequency band on the uplink in W-CDMA/HSPA Nov. 26, 2013
8588344 Detecting the modulation type and/or constellation order of a PSK/QAM-modulated signal Nov. 19, 2013
8588338 Driver circuit for driving a power amplifier Nov. 19, 2013

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