Maximum Likelihood Decoder Or Viterbi Decoder Patents (Class 375/262)
  • Patent number: 8355471
    Abstract: A receiver includes a constellation processing module and a multi-stage demodulator having a plurality of non-final demodulation stages and a final demodulation stage. The constellation processing module derives a set of centroid-based values from subsets of constellation points associated with a plurality of transmitted signals for input to each of the non-final demodulation stages. Each of the non-final demodulation stages demodulates a group of signals input to the non-final demodulation stage using the set of centroid-based values as constellation points and suppresses residual interference associated with using the set of centroid-based values as constellation points for signal demodulation. The final demodulation stage demodulates a group of modified signals input to the final demodulation stage using the subset of constellation points input to the final demodulation stage to determine a final symbol decision for the plurality of transmitted signals.
    Type: Grant
    Filed: August 27, 2009
    Date of Patent: January 15, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Ali S. Khayrallah
  • Patent number: 8351539
    Abstract: A method for transmitting and receiving a signal and an apparatus for transmitting and receiving a signal are disclosed. The method for receiving the signal includes receiving (S210) the signal in a first frequency band, identifying (S220) a first pilot signal including, a cyclic prefix obtained by frequency-shifting a first portion of an useful portion of the first pilot signal and a cyclic suffix obtained by frequency-shifting a second portion of the useful portion of the first pilot signal from the received signal, demodulating (S220) a signal frame including a physical layer pipe (PLP) to which a service stream is converted, by an orthogonal frequency division multiplexing (OFDM) scheme, using information set in the first pilot signal, parsing (S230) the signal frame and obtaining the PLP and obtaining (S240) the service stream from the PLP.
    Type: Grant
    Filed: December 11, 2008
    Date of Patent: January 8, 2013
    Assignee: LG Electronics Inc.
    Inventors: Woo Suk Ko, Sang Chul Moon
  • Patent number: 8351543
    Abstract: An active antenna array comprises a plurality of transmission paths, a predistortion modulation signal generator, and a predistortion modulation signal distribution structure. At least two of the plurality of transmission paths comprise a predistortion modulator for modulating a transmission path signal with a predistortion modulation signal generated by the predistortion modulation signal generator and distributed by predistortion modulation signal distribution structure to the at least two of the plurality of transmission paths. A method for predistorting at least two of a plurality of transmission path signals in an active antenna array and computer program products for manufacture and method execution are also claimed.
    Type: Grant
    Filed: December 21, 2009
    Date of Patent: January 8, 2013
    Assignee: Ubidyne, Inc.
    Inventor: Peter Kenington
  • Patent number: 8345791
    Abstract: A method is provided for receiving a received signal corresponding to a multicarrier signal transmitted by at least one transmitter via a transmission channel, the multicarrier signal being formed by a temporal succession of symbols including of a set of data elements with real values, including informative data elements, and reference data elements called pilots for at least some of the symbols. The reception method includes step of first estimation of the transmission channel. Due to at least one of the pilots being an isolated pilot in transmission, the reception method further includes a step of extracting the isolated pilot, and a step of locally refining the first estimation.
    Type: Grant
    Filed: July 11, 2007
    Date of Patent: January 1, 2013
    Assignee: France Telecom
    Inventors: Chrislin Lele, Jean-Philippe Javaudin, Pierre Siohan
  • Patent number: 8345800
    Abstract: A receiver includes a sample and hold circuit that receives a signal (continuous time signal) that has been subject to frequency division multiplexing modulation, converts the signal to a discrete time signal, and outputs the discrete time signal, a discrete time filter that receives the signal output from the sample and hold circuit and attenuates a frequency component of a subcarrier different from a specified subcarrier, and a demodulation unit that extracts a digital baseband from a signal that has passed through the discrete time filter to complete a demodulation operation within one data symbol reception period.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: January 1, 2013
    Assignee: NEC Corporation
    Inventor: Haruya Ishizaki
  • Patent number: 8345784
    Abstract: Techniques for spherical decision-feedback sequence estimation are disclosed. A received signal is equalized by forming a trellis comprising a plurality of stages, each stage corresponding to a symbol time and comprising a plurality of nodes, each having a node state. A most likely received symbol sequence is identified by evaluating cumulative state metrics for the nodes according to MLSE or DFSE criteria. The trellis is formed by selecting a set of fan-out branches for each node by identifying, of all possible state transition branches from the node to successor nodes in the succeeding stage, those state transition branches that have a spherical branch metric less than a pre-determined metric limit, and determining the cumulative state metric for each node as a function of the cumulative state metrics for predecessor nodes in the preceding stage and the spherical branch metrics for fan-out branches connecting the predecessor nodes to the node.
    Type: Grant
    Filed: June 5, 2009
    Date of Patent: January 1, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Ali S. Khayrallah
  • Patent number: 8340202
    Abstract: 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.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: December 25, 2012
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Fredrik Huss, Yi-Pin Eric Wang
  • Patent number: 8340231
    Abstract: Techniques are provided for detecting a coded signal in the presence of non-Gaussian interference. In an embodiment, a primary transmitter corresponds to a desired transmitter, and one or more secondary transmitters correspond to interfering transmitters. In an embodiment, received symbols, which include non-Gaussian interference and additive noise, are decoded to determine a set of message bits. In an embodiment, an estimate of the set of message bits may be determined using a minimum-distance detector or an optimal-ML detector, for example, depending on the signal-to-noise and/or signal-to-interference ratios at a receiver.
    Type: Grant
    Filed: June 25, 2010
    Date of Patent: December 25, 2012
    Assignee: Marvell International Ltd.
    Inventor: Jungwon Lee
  • Patent number: 8340204
    Abstract: A Viterbi trellis processing technique in which soft decisions and hard decisions are derived from a received signal and the soft decisions are enhanced by being modified using the hard decisions. A log likelihood ratio for a bit of the received signal can be derived by grouping candidate metrics associated with the decision that the bit has a first state, grouping candidate metrics associated with the decision that the bit has a second state, applying respective functions to the groups and calculating the difference of the function values.
    Type: Grant
    Filed: August 5, 2005
    Date of Patent: December 25, 2012
    Assignees: MStar Semiconductor, Inc., MStar Software R&D (Shenzhen) Ltd., MStar France SAS, MStar Semiconductor, Inc.
    Inventors: Navid Fatemi-Ghomi, Cyril Valadon
  • Patent number: 8341489
    Abstract: Permuted accelerated LDPC (Low Density Parity Check) decoder. This decoding approach operates by processing, in parallel, selected rows for multiple individual LDPC matrix rows from various sub-matrix rows (e.g., first group of rows from a first sub-matrix row, second group of rows from a second sub-matrix row, etc.). A memory structure of daisy chains is employed for memory management of APP (a posteriori probability) values and also for check edge messages/intrinsic information (?) values. A first group of daisy chains may be employed for memory management of the APP values, and a second group of daisy chains may be employed for memory management of the check edge messages. These daisy chains operate to effectuate the proper alignment of APP (or gamma(?)) values and check edge message/intrinsic information (?) values for their respective updating in successive decoding iterations.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: December 25, 2012
    Assignee: Broadcom Corporation
    Inventors: Alvin Lai Lin, Andrew J. Blanksby
  • Patent number: 8340226
    Abstract: A multiantenna receiving device is provided to make it possible to cope with both improvement in error rate characteristic and simplification in structure. The multiantenna receiving device is comprised of soft judgement output units for carrying out a soft judgement of a modulation signal in accordance with signal point distances between a plurality of candidate signal points with respect to a plurality of multiplexed modulation signals and a receiving signal, decoding units for obtaining digital data of the modulation signals by using the judged results obtained by the soft judgement output units, and signal point decreasing units for decreasing the number of the candidate signal points used in the soft judgement output units by recursively using a part of the digital data except self-modulation signals obtained by the decoding units.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: December 25, 2012
    Assignee: Panasonic Corporation
    Inventors: Yutaka Murakami, Shutai Okamura, Takaaki Kishigami
  • Patent number: 8341488
    Abstract: Accumulating LDPC (Low Density Parity Check) decoder. The accumulating decoding architecture described herein is applicable to LDPC codes operating on a parity check matrix, H, consisting of CSI (Cyclic Shifted Identity) sub-matrices (or matrix sub-blocks) or permuted identity sub-matrices (or matrix sub-blocks). In such a structure, the entire LDPC matrix is broken into square sub-matrices such that each sub-matrix consists of either a CSI sub-matrix or a permuted identity sub-matrix, or a null matrix. The iterative decoding process operates by updating of APP (a posteriori probability) or gamma (?) values and check edge message (?) values, and this by updating one or more individual rows within a number of sub-matrix rows (or all sub-matrix or sub-block rows) are processed in parallel. The amount of parallelism is specified by the designer and is typically an integer divisor of the sub-matrix (or sub-block) size.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: December 25, 2012
    Assignee: Broadcom Corporation
    Inventors: Andrew J. Blanksby, Alvin Lai Lin
  • Patent number: 8331426
    Abstract: A method, a system, and an apparatus for improving throughput performance of an SDMA system are disclosed herein. The method includes BTS receiving feedback information sent by a UE, where the feedback information comprises an ID of a preferred beam of the UE in a pre-coding codebook, information related to a channel vector modulus value, and information about phase difference between a channel vector and the preferred beam of the UE, and the BTS using a set estimation algorithm to estimate sum throughputs supported by a current SDMA system in each sending mode according to the received feedback information and information about space correlation between multiple antennas of the BTS, selecting a maximum sum throughput among the estimated sum throughputs, and using the sending mode corresponding to this sum throughput to send data. The method, system, and apparatus provided herein improve transmitting performance of the SDMA system.
    Type: Grant
    Filed: June 14, 2010
    Date of Patent: December 11, 2012
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Luxi Yang, Yongming Huang, Yuanqian Luo, Yinggang Du
  • Patent number: 8331474
    Abstract: The transmission apparatus performs orthogonalization processing to each of the signal sequence obtained by dividing each of the more than one transmission streams into more than one signal sequence based on the orthogonality of wireless resources. The signal sequence is then sent from multiple antennas. The reception apparatus performs the orthogonal separation processing based on the above orthogonality to the received signals to separate multiple reception signal sequence having the orthogonal characteristic, and applies a predetermined signal separation scheme based on the propagation path estimation matrix between the reception apparatus and the transmission apparatus to any one of the pairs of the separated reception signal sequence, thereby separating a signal sequence before subjected to the above orthogonalization processing.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: December 11, 2012
    Assignee: Fujitsu Limited
    Inventor: Toshio Kawasaki
  • Patent number: 8331470
    Abstract: A communication system that performs encoding and decoding for communication includes a transmitting apparatus and a receiving apparatus. The transmitting apparatus includes a turbo encoding unit including a first encoding unit that encodes an input signal and generates a first parity bit by bit-based encoding and n (n=1, 2, 3, . . . ) second encoding units that encode the input signal and generate second parity bits by bit-based encoding, and a symbol mapping unit that maps an output from the turbo encoding unit to a symbol by bit-based mapping operation and modulates the output. And the receiving apparatus includes a demodulating unit that demodulates a transmission signal, and a turbo decoding unit that performs turbo decoding on the demodulated signal by bit-based decoding.
    Type: Grant
    Filed: October 8, 2009
    Date of Patent: December 11, 2012
    Assignee: Fujitsu Limited
    Inventor: Masahiko Shimizu
  • Patent number: 8331425
    Abstract: A system, method and apparatus, provide for the utilization of the MIMO technique with single-antenna communication devices that maximize high-speed broadband communication. The apparatus includes a wireless communication interface (WCI) device configured to exchange wireless signals with a base station through a multiple input multiple output (MIMO) air interface and to exchange a corresponding set of wireless signals with an access terminal through a wideband air interface having a greater bandwidth than the bandwidth of the MIMO air interface. The system includes a plurality of WCI devices communicating with the base station and exchanging corresponding signals with the access terminal.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: December 11, 2012
    Assignee: KYOCERA Corporation
    Inventors: Julien Nicolas, Amit Kalhan
  • Patent number: 8331475
    Abstract: Systems and methods for detecting data in a multiple input/multiple output signal. The method includes receiving a first signal associated with a first data value and a second signal associated with a second data value. A distance value between the received second signal and each possible second data value is calculated. Coordinates for a hypothetical first signal in light of a first possible second data value are calculated, and the first coordinate value is quantized to a nearest constellation point. A distance value between the received second signal and each possible second data value is calculated using the calculated constellation points. A determination is made of a log-likelihood ratio based on the determined distance values.
    Type: Grant
    Filed: March 18, 2009
    Date of Patent: December 11, 2012
    Assignee: Marvell International Ltd.
    Inventors: Arul Durai Murugan Palanivelu, Leilei Song, Rohit U. Nabar, Jungwon Lee, Sayandev Mukherjee, Hui-Ling Lou
  • Patent number: 8327239
    Abstract: A communication device configured to perform packet reception processing, with the header of a packet including a header sequence and a Reed-Solomon code, includes: a header check sequence inspecting unit configured to detect, based on the header check sequence included in a received packet header, an error of the header; a Reed-Solomon encoding unit configured to encode the header of a received packet other than the Reed-Solomon code to generate a Reed-Solomon code; a Reed-Solomon code inspecting unit configured to detect whether or not the Reed-Solomon code generated by the Reed-Solomon encoding unit is completely identical to the Reed-Solomon code within the received packet header; and a processing control unit configured to control payload processing of a received packet in accordance with the inspection results of the header check sequence inspecting unit and the Reed-Solomon code inspecting unit.
    Type: Grant
    Filed: February 5, 2008
    Date of Patent: December 4, 2012
    Assignee: Sony Corporation
    Inventors: Hiroyuki Yamasuge, Mitsuhiro Suzuki
  • Patent number: 8325840
    Abstract: A method and apparatus for tree position adaptive SOMA receiver structures are disclosed herein. In one embodiment, a device for use in a wireless communication system comprises a receiver to receive information-bearing signals from the transmitter wirelessly transmitted using OFDM and bit interleaved coded modulation, where the receiver includes an inner decoder structure having a soft output M-algorithm (SOMA) based multiple-in multiple-out (MIMO) joint demapper that uses a SOMA-based MIMO detection process to perform joint inner demapping over each tone, and wherein the SOMA-based MIMO joint demapper is operable to search a detection tree for each tone using a tree-search symbol order that is adapted for each tone based on channel state information and extrinsic information from the outer decoder, where only a number of best alternatives from every level of the tree are expanded.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: December 4, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Ozgun Bursalioglu, Haralabos Papadopoulos, Carl-Erik W. Sundberg
  • Patent number: 8325826
    Abstract: Base stations transmit strip signals using strip signal segments and self supporting modulation scheme techniques facilitating rapid channel estimate. A strip segment occupies one OFDM symbol time interval and uses a set of downlink tones; some, e.g., half, of the tones are left unused facilitating SIR measurement. The strip segments are advantageously timed to correspond to uplink access intervals in which connected wireless terminals do not typically transmit uplink signals. Connected wireless terminals including: multiple antennas used in combination, an antenna duplex module, single RF receiver chain and single RF transmitter chain, switch antenna coefficient combinations based on strip signal segment timing. The wireless terminal determines an independent downlink channel quality measurement, e.g., SNR and/or SIR for each strip signal segment and for on-going non-strip signaling.
    Type: Grant
    Filed: October 13, 2005
    Date of Patent: December 4, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Frank A. Lane
  • Patent number: 8320485
    Abstract: A vestigial sideband (VSB) modulation transmission system and a method for encoding an input signal in the system are disclosed. According to the present invention, the VSB transmission system includes a convolutional encoder for encoding an input signal, a trellis-coded modulation (TCM) encoder for encoding the convolutionally encoded signal, and a signal mapper mapping the trellis-coded signal to generate a corresponding output signal. Different types of the convolutional encoders are explored, and the experimental results showing the performances of the VSB systems incorporating each type of encoders reveals that a reliable data transmission can be achieved even at a lower input signal to noise ratio when a convolutional encoder is used as an error-correcting encoder in a VSB system.
    Type: Grant
    Filed: September 21, 2009
    Date of Patent: November 27, 2012
    Assignee: LG Electronics Inc.
    Inventors: In Hwan Choi, Young Mo Gu, Kyung Won Kang, Kook Yeon Kwak
  • Patent number: 8321744
    Abstract: A channel adaptive iterative turbo decoder for computing with MAP decoders a set of branch metrics for a window of received data, computing the forward and reverse recursive path state metrics and computing from the forward and reverse recursive path state metrics the log likelihood ratio for 1 and 0 and interleaving the decision bits; and identifying those MAP decoder decision bits which are non-convergent, computing a set of branch metrics for the received data, computing from the forward and reverse recursive path state metrics the log likelihood ratio (LLR) for 1 and 0 for each non-converged decision bit and interleaving the non-convergent decision bits.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: November 27, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Yosef Stein, Hazarathaiah Malepati, Haim Primo
  • Patent number: 8320429
    Abstract: There are provided a receiver in human body communication system using multiple receivers reducing an error rate of receiver signals by applying a space diversity acquisition-related SIMO technology to a plurality of received data using multiple receivers or receiver electrodes in a human body communication system using a human body as a medium, and of stably transmitting the data for the interference of signals generated by other users or from different electronic devices, and a method for receiving data in the human body communication system. The receiver and the method for receiving data in a human body communication system may be useful to stably transmit/receive data without any reduction of its transmission rate by reducing the distortion in channels and the signal noise which are caused in the use of one receiver.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: November 27, 2012
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Tae Wook Kang, In Gi Lim, Hyung Il Park, Sung Weon Kang, Kyung Soo Kim, Jung Bum Kim, Chang Hee Hyoung, Duck Gun Park, Sung Eun Kim, Jung Hwan Hwang, Ki Hyuk Park, Jae Hoon Shim, Jin Kyung Kim
  • Patent number: 8320475
    Abstract: A system for measuring inter-carrier interference (ICI) in an OFDM system includes a test symbol generator coupled to a transmitter of the OFDM system to generate an N*N orthogonal matrix having N*N test symbols, and to send the test symbols in a test symbol stream via the transmitter to a receiver of the OFDM system. The N*N test symbols are arranged by the test symbol generator into an N*N orthogonal matrix before being sent to the receiver. The system also includes an ICI measuring module coupled to the receiver to detect the N*N test symbols received in the receiver and to arrange the test symbols as a receiving matrix in the same way as the orthogonal matrix in the transmitter. The ICI measuring module outputs the receiving matrix as an ICI matrix of the OFDM system, wherein an element on the kth row, lth column of the ICI matrix represents interference from the lth sub-carrier on the kth sub-carrier, wherein k?l.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: November 27, 2012
    Assignee: Agilent Technologies, Inc.
    Inventors: Danxun Shen, Hong Wei Kong, Xu Zhao
  • Patent number: 8316285
    Abstract: Methods and apparatus for performing error correction of data bits are disclosed. A forward metric calculation may be performed during a first window to generate a first group of calculated data. The first group of calculated data from the forward calculation may be stored in a memory location. A forward metric calculation may be performed during a second window to generate a second group of calculated data. The first group of calculated data may be read from the memory location and the second group of calculated data may be stored in the same memory location. The first group of calculated data may be used to calculate reverse metrics.
    Type: Grant
    Filed: March 10, 2011
    Date of Patent: November 20, 2012
    Assignee: InterDigital Technology Corporation
    Inventors: Edward L. Hepler, Michael F. Starsinic
  • Patent number: 8315574
    Abstract: A method for communication includes transmitting data from a transmitter to a receiver using Adaptive Coding and Modulation (ACM). The data rate is set by selecting, based on feedback, an ACM profile defining a Forward Error Correction code and a modulation scheme. Upon detecting that the feedback is unusable, an operation of the transmitter is changed independently of the feedback. In another method, data is exchanged over two opposite directions of a bidirectional link that uses ACM by communicating using two ACM profiles. A joint constraint is defined on the two directions. The two ACM profiles are set based on first and second measured reception quality metrics of the two link directions, to meet the joint constraint. In yet another method, a subset of the ACM profiles is temporarily disabled, and the data is transmitted using only the ACM profiles that are not disabled.
    Type: Grant
    Filed: April 13, 2007
    Date of Patent: November 20, 2012
    Assignee: Broadcom Corporation
    Inventors: Ehud Ashkenazi, Jonathan Friedman
  • Patent number: 8311161
    Abstract: Systems and methods detect a communication received at receiving antennas from transmitting antennas. Each transmitting antenna transmits a symbol in a constellation. A sphere detector performs a depth-first search until the depth-first search terminates in response to a terminate signal requesting the result from the sphere detector. The depth-first search evaluates respective distances of one or mode leaf nodes in response to the communication received at the receiving antennas. The depth-first search selects the result from these nodes in response to the respective distances. The result includes a selected leaf node that identifies a corresponding symbol in the constellation for each transmitting antenna, with this symbol detected as transmitted by the transmitting antenna.
    Type: Grant
    Filed: June 19, 2009
    Date of Patent: November 13, 2012
    Assignee: Xilinx, Inc.
    Inventors: Jorn W. Janneck, Christopher H. Dick
  • Patent number: 8306139
    Abstract: Systems and methods for providing multiple-input multiple-output (MIMO) detection, comprising a leaf node predictor for receiving a processed communications stream, computing at least one channel metric corresponding to the communications stream for a given channel realization, and generating at least one parameter corresponding to at least one predicted best leaf node candidate for the given channel realization. A MIMO engine receives the at least one parameter and enumerates at least one list of candidate vectors corresponding to the leaf nodes specified by the generated at least one parameter. Some embodiments simulate a MIMO detector over many channel realizations, track channel metric and parameter values used for each channel realization resulting from such simulating, and store, in a look-up table, best values of the tracked values used for a particular channel metric.
    Type: Grant
    Filed: January 18, 2008
    Date of Patent: November 6, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: David L. Milliner, Deric W. Waters, Anuj Batra, Srinath Hosur
  • Patent number: 8306130
    Abstract: A TFI-OFDM transmission system for a UWB communication that includes a data generator generating data having a rate corresponding to a transmission speed mode, a convolutional encoder convolutional-encoding the data into a certain number of data groups, an OFDM modulator outputting OFDM symbols by executing an IFFT the data groups a buffer temporarily storing the OFDM symbols to sequentially transmit the OFDM symbols in a time domain at least two times, and a frequency generator generating certain frequencies to transmit the OFDM symbols in a certain number of frequency bands corresponding to transmission channels.
    Type: Grant
    Filed: July 14, 2004
    Date of Patent: November 6, 2012
    Assignees: Samsung Electronics Co., Ltd., Veebeam Corporation
    Inventors: Seung-young Park, Yong-suk Kim, Torbjorn Larsson, Roberto Aiello
  • Patent number: 8300713
    Abstract: A preamble sequence detection and integral carrier frequency offset estimation method for OFDM/OFDMA wireless communication systems by formulating integral carrier frequency offset estimation and preamble sequence detection as a signal detection problem in multi-channel interference, obtaining the theoretically optimal solution, and deriving simplified, approximately optimal solutions, in which frequency-domain filtering is employed to calculate the required correlation values, which can drastically reduce the high computational complexity of the original theoretically optimal solution but result in little impact on precision. In addition, several further simplified algorithms are provided, some of which can even eliminate the use of multipliers. The using of frequency-domain filtering has high extensibility in application to related signal sequence detection problems.
    Type: Grant
    Filed: April 2, 2008
    Date of Patent: October 30, 2012
    Assignee: National Chiao Tung University
    Inventors: Kun-Chien Hung, David W. Lin
  • Patent number: 8295335
    Abstract: Techniques are described that provide uplink power control techniques that can support different uplink multi-input multi-output (MIMO) transmission schemes. A mobile station determines a Signal to Interference-plus-Noise Ratio based on base and offset values transmitted from a base station. The base station can transmit the base and offset values using seven bits total. The mobile station determines an uplink transmitter power level based on the Signal to Interference-plus-Noise Ratio.
    Type: Grant
    Filed: May 19, 2010
    Date of Patent: October 23, 2012
    Assignee: Intel Corporation
    Inventor: Rongzhen Yang
  • Patent number: 8296624
    Abstract: In cable modem termination systems (CMTS) and other information transmission systems, a method for changing the interleave depth associated with each data stream is provided. This may be done dynamically, and for any subset of downstream devices such as modems. The interleave depth may be set on an individual device level. Embodiments may decrease data receiving latency on devices that do not suffer from error rates, such as caused by burst noise, while maintaining throughput on devices with high error rates.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: October 23, 2012
    Assignee: Comcast Cable Communications, LLC
    Inventor: Ross O. Gilson
  • Patent number: 8295409
    Abstract: A multi-sensor signal fusion apparatus is provided for automatic modulation classification of weak unknown signals in non-cooperative communication environment with a more accurate description of the signal. The multi-sensor non-cooperative demodulation device combines a group of sensors, a signal fusion sensor, a means for signal demodulation, and a means for automatic modulation classification. An output of the signal fusion sensor is sent to a means for modulation scheme classification to select the appropriate demodulation technique for demodulating the unknown signal and provide the necessary intelligence about the monitored signals to the user and allow the user to simulate the unknown non-cooperative signal.
    Type: Grant
    Filed: December 14, 2011
    Date of Patent: October 23, 2012
    Assignee: The United States of America as Represented by the Secretary of the Army
    Inventor: Wei Su
  • Patent number: 8295378
    Abstract: Various aspects of a method for minimum mean square error soft interference cancellation (MMSE-SIC) based sub-optimal maximum likelihood (ML) detection for a multiple input multiple output (MIMO) wireless system may comprise selecting at least one constellation point in a constellation map based on at least one of a plurality of received symbols. A number of the at least one constellation point may be less than or equal to a number of previously selected constellation points in a previous constellation map. At least one of the plurality of received symbols may be decoded based on the selected at least one constellation point.
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: October 23, 2012
    Assignee: Broadcom Corporation
    Inventors: Ling Su, George Kondylis
  • Patent number: 8295379
    Abstract: A system and method for non-uniform bit allocation in the quantization of channel state vectors is provided. A method for communications node operation includes receiving a bit-allocation profile for use in quantizing channel state information, measuring a communications channel between the communications node and a controller, generating channel state information based on the measurement, computing a bit representation of the channel state information, transmitting the bit representation to the controller, and receiving a transmission from the controller. The computing makes use of quasi-tail-biting trellis decoding, and the computing is based on the bit-allocation policy. The transmission makes use of the channel state information transmitted by the communications node.
    Type: Grant
    Filed: December 8, 2009
    Date of Patent: October 23, 2012
    Assignee: FutureWei Technologies, Inc.
    Inventors: Chun Kin Au-Yeung, Shahab Sanayei
  • Patent number: 8290078
    Abstract: A method of encoding a stream of data elements is provided which involves splitting the stream of data elements into a first stream and a second stream; encoding the first stream to produce a first encoded stream; performing a constellation mapping using a combination of the first encoded stream and a third stream which is based on the second stream. This may involve defining a signal constellation; defining a plurality of co-sets within the constellation such that a minimum distance between constellation points within each co-set is larger than a minimum distance between any constellation points within the signal constellation; performing said constellation mapping by using the first encoded stream to identify a sequence of co-sets of said plurality of co-sets, and by using the third stream to identify a sequence of constellation points within respective co-sets of the sequence of co-sets identified by said first encoded stream.
    Type: Grant
    Filed: August 16, 2010
    Date of Patent: October 16, 2012
    Assignee: Apple Inc.
    Inventors: Wen Tong, Amir Khandani
  • Patent number: 8290095
    Abstract: A Viterbi pack instruction is disclosed that masks the contents of a first predicate register with a first masking value and masks the contents of a second predicate register with a second masking value. The resulting masked data is written to a destination register. The Viterbi pack instruction may be implemented in hardware, firmware, software, or any combination thereof.
    Type: Grant
    Filed: March 23, 2006
    Date of Patent: October 16, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Mao Zeng, Lucian Codrescu
  • Patent number: 8290035
    Abstract: Digital television broadcasting signals employ parallel concatenated convolutional coding, commonly called “turbo coding”, to improve reception by receivers in motor vehicles. Turbo coded Reed-Solomon codewords are transversally disposed in the payload fields of encapsulating MPEG-2-compliant packets to improve the capability of the Reed-Solomon coding to overcome deep fades. Turbo codewords are transmitted more than once in so-called “staggercasting”. Reception of DTV signals is improved by combining soft decisions concerning repeated transmissions of turbo codewords before turbo decoding. Only the data components of turbo codewords are transmitted twice in “punctured” staggercasting of turbo codewords, with parity components being transmitted only once, so code rate is reduced by a smaller factor than two.
    Type: Grant
    Filed: July 11, 2008
    Date of Patent: October 16, 2012
    Inventor: Allen LeRoy Limberg
  • Patent number: 8290097
    Abstract: A multi-channel sequential Viterbi decoder includes: an input data buffer, a “Read Single Data Word from Input Data Buffer” signal driver, a processing unit selector, a decoder channel parameters registers unit, a processing unit for the “Reset Path Metrics” command, a processing unit for the “Set Path Metric Value for the Given Path Number” command, a processing unit for the “Get Single Bit from the Path with Given Number” command, a processing unit for the “Process Input Samples” command, a decoding paths and path metrics RAM, a unit for generating current decoder channel base address for the decoding paths and path metrics RAM, a unit for generating cell address for the decoding path and path metric RAM, and a data buffers unit for decoder channels output.
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: October 16, 2012
    Assignee: Topcon Positioning Systems, Inc.
    Inventors: Timur G. Kelin, Dmitry D. Murzinov, Dmitry A. Pyatkov
  • Patent number: 8284869
    Abstract: A method of demodulating a signal on which is modulated, using a quadrature amplitude modulation scheme, a plurality of information symbols, the method including: determining at least one QAM detection threshold corresponding to one or more of said information symbols; and demodulating each information symbol on the basis of at least one respective QAM detection threshold.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: October 9, 2012
    Assignee: NEC Corporation
    Inventors: Xinhua Wang, Nikolay Vaptzarov, Shikand Satheesh
  • Patent number: 8284873
    Abstract: A wireless communication receiver includes a first signal processing block, a second signal processing block, and a de-interleaver. The first signal processing block is configured for receiving a wireless communication signal and processing the wireless communication signal to generate a first output. The de-interleaver is coupled between the first signal processing block and the second signal processing block, and includes a plurality of branches implemented for de-interleaving the first output to generate a second output. The de-interleaver starts outputting the second output to the second signal processing block for further signal processing before all buffers included in the branches are full, and informs the second signal processing block of data derived from one or more unfull buffers included in the branches.
    Type: Grant
    Filed: April 7, 2009
    Date of Patent: October 9, 2012
    Assignee: Mediatek Inc.
    Inventor: Shun-An Yang
  • Patent number: 8279986
    Abstract: Provided are: plural circuit components including a circuit component which constitutes a receiving unit receiving a signal sequence which is arranged so that a desired signal and a signal different from the desired signal are lined up in time series, the desired signal indicating desired data which includes at least one of text data, sound data, image data, and a computer program product; and an operating parameter changing unit which changes an operating parameter of at least one of the plural circuit components, during a period in which the receiving unit receives the signal different from the desired signal.
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: October 2, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Nobuyoshi Kaiki
  • Patent number: 8279979
    Abstract: Disclosed herein is a signal processing apparatus that processes a signal transmitted over a transmission path that causes stationary distortion to occur in a waveform representing a signal value of a specific symbol in accordance with a value of a symbol transmitted before the specific symbol.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: October 2, 2012
    Assignee: Sony Corporation
    Inventors: Shunsuke Mochizuki, Takashi Nakanishi, Ryosuke Araki, Seiji Wada, Masahiro Yoshioka, Hiroto Kimura, Hiroshi Ichiki, Tetsujiro Kondo
  • Patent number: 8279977
    Abstract: A signal decoder, a method of detecting an RF signal at a MIMO receiver and a MIMO receiver are disclosed herein. In one embodiment, the signal decoder includes: (1) a tree pruner configured to reduce a number of nodes of an MLD tree to expand based on modulation properties of the transmitted radio signals and SE enumeration of at least a portion of the MLD tree and (2) a vector sorter configured to sort multiple rows of child nodes of the MLD tree in parallel.
    Type: Grant
    Filed: December 14, 2010
    Date of Patent: October 2, 2012
    Assignee: Verisilicon
    Inventor: Jitendra Rayala
  • Patent number: 8279954
    Abstract: A method and apparatus is disclosed herein for forward-backward SOMA techniques. In one embodiment, the apparatus is a receiver comprising: an inner decoder structure having a soft output M-algorithm (SOMA) based multiple-in multiple-out (MIMO) joint demapper that uses a SOMA-based MIMO detection process to perform joint inner demapping over each tone, where the SOMA-based MIMO joint demapper is operable to identify a best candidate among a number of candidates by searching a detection tree for each tone using a forward pass through the detection tree, where only a number of best alternatives from every level of the tree are expanded and where soft-output related information is collected and stored, and to perform a second pass, following the forward pass, during which soft-output is computed for each bit; and an outer decoder operable with the SOMA-based inner decoder to perform iterative decoding.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: October 2, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Haralabos Papadopoulos, Carl-Erik W. Sundberg
  • Patent number: 8279974
    Abstract: Various techniques for dynamically reducing power usage in a wireless receiver are disclosed. A receiver unit receives a wireless signal over a channel and processes the wireless signal, including dynamically changing one or more of the settings of the receiver unit to control its power usage. These setting are changed in response to one or more power setting values that are generated based on a first set of information that includes state information for the channel. The receiver unit may dynamically change a first setting that causes the bias current applied to an analog-to-digital converter to be changed. The channel state information may include information indicative of a received signal strength indication (RSSI), information indicative of a packet error rate (PER) for packets encoded on the wireless signal, and header error check (HEC) and/or cyclical redundancy check (CRC) errors for data packets encoded on the wireless signal.
    Type: Grant
    Filed: November 4, 2008
    Date of Patent: October 2, 2012
    Assignee: QUALCOMM Atheros, Inc.
    Inventors: Paul J. Husted, Soner Ozgur
  • Patent number: 8275086
    Abstract: An apparatus for frequency synchronization is proposed to detect a synchronization signal from the baseband signals. It is featured that three types of detection values are introduced to detect whether the synchronization signal is received or not. More particularly, the claimed frequency synchronization apparatus provides at least one signal power generator for receiving a predetermined number of symbols of the baseband signals, and further calculating an average quality value therefore. Further, the apparatus includes a signal selector for producing a first detection value according to the average quality value. Still further, the apparatus provides a decision unit to produce a second detection value. After that, a signal processor inside the decision unit is used to calculate a third detection value as combining the first detection value and the second detection.
    Type: Grant
    Filed: October 16, 2009
    Date of Patent: September 25, 2012
    Assignee: Mediatek Incorporation
    Inventors: Wei-Nan Sun, Ho-Chi Huang
  • Patent number: 8275077
    Abstract: The present invention pertains to demodulation of GMSK signals by estimating a carrier frequency of the signal having a carrier residual, basebanding the signal, tracking the signal's carrier frequency, removing the carrier residual, detecting a data burst, generating a bank of poly-bit matched filters, applying the bank of poly-bit matched filters to the signal, determining a magnitude and phase of the output of each poly-bit filter of the bank of poly-bit matched filters, determining a maximum magnitude, determining the location of a baud center, generating a plurality of correlation signals by applying the bank of poly-bit matched filters at the baud center, estimating a carrier phase, removing the estimated carrier phase, applying a Viterbi decoding algorithm to the signal, and estimating the transmitted data sequence.
    Type: Grant
    Filed: October 13, 2010
    Date of Patent: September 25, 2012
    Assignee: The United States of America as Represented by the Director, National Security Agency
    Inventor: Douglas J. Nelson
  • Patent number: 8275082
    Abstract: Certain aspects of a method and system for a delay locked loop for a rake receiver are disclosed. Aspects of one method may include normalizing a signal power of a first control channel based on a threshold value. A sampling time associated with at least one or more of the following: the first control channel, a second control channel, an on-time control channel, and a data channel, may be adjusted based on a comparison between the normalized signal power of the first control channel and a signal power of the second control channel. The second control channel may be delayed with respect to the first control channel by a particular time period. The first and second control channels may be common pilot control channels (CPICHs). The combined signal power of the first control channel may be normalized based on said threshold value.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: September 25, 2012
    Assignee: Broadcom Corporation
    Inventors: Hongwei Kong, Li Fung Chang, Huaiyu Zeng
  • Patent number: 8270515
    Abstract: There is provided a system and method of operating a multiple-input multiple-output (MIMO) receiver with N antennas in a wireless communication system. The method includes measuring N vectors, each vector defining channel transfer coefficients between M antennas of a transmitter and a corresponding antenna of the receiver. Additionally, a vector in a linear space generated by the N measured vectors is selected and quantized values of less than M components of the selected vector are fed back to the transmitter.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: September 18, 2012
    Assignee: Alcatel Lucent
    Inventor: Alexei Ashikhmin