Maximum Likelihood Decoder Or Viterbi Decoder Patents (Class 375/262)
  • Patent number: 9171540
    Abstract: A method and an apparatus for speech signal processing are provided. The method includes: receiving an encoded speech signal sent by a user equipment, where the encoded speech signal includes a first substream, a second substream, and a third substream, and the first substream is attached with a cyclic redundancy check (CRC); performing decoding processing on the first substream, the second substream, and the third substream by adopting a decoding algorithm, where a decoding algorithm that is based on an auxiliary decision of the CRC is adopted to perform decoding processing on the first substream; and sending decoding results of the first substream, the second substream, and the third substream to a base station controller, where the decoding result of the first substream includes a decoded bit stream and a CRC result. Decoding performance of the first substream is improved, and users' higher requirements for the speech quality are met.
    Type: Grant
    Filed: November 27, 2013
    Date of Patent: October 27, 2015
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Yuejun Wei, Xin Tang, Qian Zhu
  • Patent number: 9166740
    Abstract: Systems and methods are provided for determining a data value for a bit of interest in a received data signal. A closest 0-bit symbol candidate is selected from a plurality of 0-bit symbol candidates using a symbol selection distance approximation. A closest 1-bit symbol candidate is selected from a plurality of 1-bit symbol candidates using the symbol selection distance approximation. A 0-bit distance between the received data signal and the selected 0-bit symbol candidate is determined, and a 1-bit distance between the received data signal and the selected 1-bit symbol candidate is determined. A log likelihood ratio is calculated for the bit of interest using the determined 0-bit distance and the determined 1-bit distance.
    Type: Grant
    Filed: January 28, 2014
    Date of Patent: October 20, 2015
    Assignee: MARVELL INTERNATIONAL LTD.
    Inventors: Adina Matache, Leilei Song, Bhaskar V. Nallapureddy, Hui-Ling Lou
  • Patent number: 9155040
    Abstract: Access terminals are adapted to facilitate power conservation by selectively powering down one or more hardware block when processing a general page message (GPM) received in slotted idle mode. An access terminal may include a processor core, a de-interleaver, a decoder and a firmware block. The firmware block may be adapted to enable the processor core to sleep while the firmware block collects samples of a received transmission and extracts symbols from the collected samples. The firmware block may further power ON the de-interleaver to de-interleave the extracted symbols, and the decoder to decode the de-interleaved symbols. Other aspects, embodiments, and features are also included.
    Type: Grant
    Filed: August 24, 2012
    Date of Patent: October 6, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Bhaskara V. Batchu, Aditya Bohra, Anand Rajurkar, Nawal Kishor Mishra
  • Patent number: 9143377
    Abstract: Techniques are described for quadrature amplitude modulation (QAM) processing in a rotated QAM constellation. In the techniques, one or more processors determine points within the rotated QAM constellation around a vector location of a received symbol based on a probability density function applied to the vector location. The one or more processors map the points to corresponding mapped symbols of the rotated QAM constellation, and determine a plurality of bits represented by the transmitted symbol based on the corresponding mapped symbols.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: September 22, 2015
    Assignee: QUALCOMM Incorporated
    Inventor: Ariel Y. Sagi
  • Patent number: 9124458
    Abstract: Teachings presented herein offer reduced computational complexity for detecting a plurality of symbol blocks, even for symbol blocks that comprise the combination of a relatively large number of symbols. The teachings perform two or more stages of detection assistance to successively reduce the number of candidate combinations of symbols to be considered for a symbol block when detecting the plurality of symbol blocks. In particular, the teachings identify a reduced set of candidate symbol combinations for at least one symbol block in the plurality of symbol blocks, and then jointly detect each of one or more distinct groups of symbols in the symbol block to determine from that reduced set a final reduced set of candidate symbol combinations. Detection of the plurality of symbol blocks limits the candidate combinations of symbols considered for a symbol block to the final reduced set of candidate symbol combinations identified for that symbol block.
    Type: Grant
    Filed: September 28, 2009
    Date of Patent: September 1, 2015
    Assignee: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Gregory E. Bottomley, Yi-Pin Eric Wang
  • Patent number: 9118530
    Abstract: In a method for generating a PHY data unit for transmission via a communication channel, a modulation scheme is selected from a plurality of modulation schemes, information bits are encoded to generate encoded data using one or more encoders, and an interleaving parameter NCOL is selected using the selected modulation scheme. NCOL varies for different modulation schemes. The encoded data is interleaved, which includes entering the encoded data into NROW rows and reading the encoded data out in NCOL columns. The payload information of the PHY data unit is modulated according to the modulation scheme, and a plurality of OFDM symbols is formed based on the modulated payload information.
    Type: Grant
    Filed: March 21, 2014
    Date of Patent: August 25, 2015
    Assignee: MARVELL WORLD TRADE LTD.
    Inventors: Sudhir Srinivasa, Hongyuan Zhang, Rohit U. Nabar
  • Patent number: 9094063
    Abstract: A method of decoding a signal transmitted via a multiple input multiple output (MIMO) communication channel. The method includes receiving a data symbol vector having a plurality of data symbols received via a plurality of spatial streams. The received data symbol vector corresponds to a transmitted data symbol vector having a plurality of transmitted data symbols corresponding to the plurality of data symbols. The method also includes estimating, using a hard-decision technique, one or more respective values for one or more first transmitted data symbols in a first set of one or more spatial streams. The method additionally includes calculating, using a soft-decision technique and based on the estimated one or more respective values for the one or more first transmitted data symbols, likelihood values for bits corresponding to one or more second transmitted data symbols in a second set of one or more spatial streams.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: July 28, 2015
    Assignee: Marvell International Ltd.
    Inventors: Jungwon Lee, Hui-Ling Lou, Jiwoong Choi
  • Patent number: 9084199
    Abstract: In a 3G cellular network, a Reverse Link Channel Quality Indicator Channel (R-CQICH) may be transmitted on a reverse link to support forward link high-speed data transmissions. Accordingly, the R-CQICH may be utilized to track the quality of the signal path between the wireless unit and the base station. The base station may include a CQI component that utilizes a received Channel Quality Indicator (CQI) signal from the wireless unit to generate CQI quality metrics based on the quality of the received signal. Also, the CQI quality metrics may be compared to different thresholds to adjust various system configurations in the base station. The base station may also provide feedback to the wireless unit with the updated system configurations. This technique allows CQI quality metrics to be utilized to adjust system configurations dynamically and enhance the operation of a wireless system.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: July 14, 2015
    Assignee: Alcatel Lucent
    Inventors: Jialin Zou, Hongwei Kong
  • Patent number: 9059881
    Abstract: Embodiments of the invention provide a method of decoding of hexagonal constellations. The decoding methods exploit the inherent structure of the hexagonal grid to eliminate/minimize the requirements for distance computations. A constellation which has unused constellation points is received. A plurality of lookup tables is used for indicating whether a particular constellation point is used. The lookup tables are indexed using the two integers u and v. An initial estimate ? and v is found. The Euclidean distance to the immediate neighbors resulting in the immediate upper and lower integers for ? and v is computed. From the distance to the nearest neighbor, the log-likelihood ratio value is computed.
    Type: Grant
    Filed: October 10, 2013
    Date of Patent: June 16, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Mohamed Farouk Mansour, Lars Jorgensen
  • Patent number: 9054849
    Abstract: Methods and apparatus are provided for encoding information bits. The information bits are segmented, and one or more coded blocks are generated by adding parity bits to each segment of the information bits. Segmenting the information bits includes determining a number of coded blocks to be generated using a reference value, and segmenting the information bits based on the determined number of coded blocks.
    Type: Grant
    Filed: March 12, 2010
    Date of Patent: June 9, 2015
    Assignee: Samsung Electronics Co., Ltd
    Inventors: Se-Ho Myung, Jae-Yoel Kim, Yeon-Ju Lim, Sung-Ryul Yun, Hong-Sil Jeong
  • Patent number: 9047877
    Abstract: A DTX decision method includes: obtaining sub-band signal(s) according to an input signal; obtaining a variation of characteristic information of each of the sub-band signals; and performing DTX decision according to the variation of the characteristic information of each of the sub-band signals. With the invention, a complete and appreciate DTX decision result is obtained by making full use of the noise characteristic in the speech encoding/decoding bandwidth and using band-splitting and layered processing. As a result, the SID encoding/CNG decoding may closely follow the characteristic variation of the actual noise.
    Type: Grant
    Filed: April 20, 2010
    Date of Patent: June 2, 2015
    Assignee: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Jinliang Dai, Eyal Shlomot, Deming Zhang
  • Publication number: 20150146810
    Abstract: A method of performing a soft demapping, includes obtaining a signal from a symbol representing bits that is transmitted from a transmitter, and calculating a gradient of a reference line in a constellation for a bit based on a rotation angle and a channel state of the constellation. The method further includes selecting a candidate for each of lines that corresponds to a logic value of the bit from constellation points included in the constellation based on the signal and the gradient of the reference line, and calculating a log-likelihood ratio (LLR) of the bit based on the signal and the selected candidate for each of the lines.
    Type: Application
    Filed: October 20, 2014
    Publication date: May 28, 2015
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Ki Taek BAE, Peng XUE, Kyeong Yeon KIM, Navneet BASUTKAR, Ho YANG
  • Patent number: 9036738
    Abstract: A receiving device including: a demodulation circuit configured to generate first likelihood data of reception symbols based on a transmission format of the reception symbols, the transmission format being selected from transmission formats and including a modulation scheme applied to the reception symbols, the modulation scheme being one of amplitude modulation schemes, a processor configured to estimate a scale ratio of an implementation scale to a theoretical scale, the implementation scale being a scale of the first likelihood data, the theoretical scale being a scale of second likelihood data of the reception symbols, the second likelihood data being defined by a theory and not depending on an implementation of the receiving device, and to generate the second likelihood data based on the first likelihood data and the scale ratio, and a decoding circuit configured to decode the second likelihood data based on the transmission format.
    Type: Grant
    Filed: March 26, 2014
    Date of Patent: May 19, 2015
    Assignee: FUJITSU LIMITED
    Inventor: Shunji Miyazaki
  • Patent number: 9036688
    Abstract: Various embodiments associated with modulation scheme determination for an unknown signal with noise are described. An unknown signal can have an unknown modulation scheme to a system. In order to determine a modulation scheme to use with the unknown signal, the unknown signal can be compared to a plurality of known signals, with an individual known signal being associated with a particular modulation scheme. A rapid classification method can be used that is less computationally intensive than an average likelihood ratio test method based on the distances between unknown symbols and constellation alphabets of a set of known modulation schemes. Signal to noise ratios before and after classification can be used to check an accuracy of classification and distribution of signal symbols can be used to verify a classification result.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: May 19, 2015
    Assignee: The United States of America, as represented by the Secretary of the Army
    Inventor: Wei Su
  • Patent number: 9031145
    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: May 30, 2014
    Date of Patent: May 12, 2015
    Assignee: Marvell International Ltd.
    Inventors: Arul Durai Murugan Palanivelu, Leilei Song, Rohit U. Nabar, Jungwon Lee, Sayandev Mukherjee, Hui-Ling Lou
  • Patent number: 9032276
    Abstract: The present invention includes generating a tie-breaking metric via a comparative tie-breaking metric training process, monitoring an output of a channel detector in order to identify a tie condition between a first log-likelihood ratio (LLR) value and a second LLR value of a symbol, and upon identifying a tie condition between the first LLR value and the second LLR value of the symbol, applying the generated tie-breaking metric to the symbol in order to assign a hard decision to the symbol.
    Type: Grant
    Filed: September 25, 2012
    Date of Patent: May 12, 2015
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Wu Chang, Fan Zhang, Yang Han, Ming Jin
  • Patent number: 9025687
    Abstract: A method for a QAM receiver to decide a value of a received symbol of an N-point QAM constellation transmission including extracting coordinate values for the received symbol, and using a decision method for deciding the value of the received symbol based on the extracted coordinate values, in which the decision method for the N-point QAM constellation is updated based on a clustering of received symbols. A method for a QAM transmitter to modify an N-point QAM constellation including starting with an initial N-point QAM constellation, measuring a clustering of coordinates of the N-point QAM constellation, shifting coordinates of at least one symbol of the N-point QAM constellation, and producing a modified constellation with shifted coordinates, wherein the shifting is based on data describing a clustering of at least some symbols of the N-point QAM constellation. Related apparatus and methods are also described.
    Type: Grant
    Filed: July 1, 2013
    Date of Patent: May 5, 2015
    Assignee: Ceragon Networks Ltd.
    Inventor: Isaac Rosenhouse
  • Patent number: 9025704
    Abstract: Certain aspects of the present disclosure relate to techniques for generating likely demodulation candidates using Vector Candidate Sampling (VCS). VCS is used to generate high likelihood candidates for Multiple Input Multiple Output (MIMO) demodulation that approaches optimal maximum a posteriori (MAP) performance with reasonable complexity. A receive data vector is recorded corresponding to a signal received at a MIMO receiver. A plurality of likely candidates are determined for MIMO demodulation via VCS, based at least on the receive data vector. Determining the likely candidates may include perturbing the receive data vector for each candidate based on a pre-determined perturb vector, and estimating a corresponding transmit data vector based at least on the perturbed receive data vector for the candidate and an estimator matrix, wherein the likely candidate comprises the estimated data vector.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: May 5, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: James E. Beckman, Alexei Yurievitch Gorokhov
  • Patent number: 9026876
    Abstract: Systems and methods for computing sign disagreement between signals may implement one or more operations including, but not limited to: receiving an extrinsic log likelihood ratio (LLR) value; incrementing a sign-disagreement counter according to a sign disagreement between the extrinsic LLR value and an a priori LLR value; providing a value of the sign-disagreement counter to a binary short media defect (SMD) detector; and detecting one or more consecutive sign disagreements between an extrinsic output of a detector and an extrinsic output of a decoder.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: May 5, 2015
    Assignee: LSI Corporation
    Inventors: Fan Zhang, Wu Chang
  • Publication number: 20150117559
    Abstract: Methods, apparatuses, and systems are provided for generating a candidate search set for ML detection of 2n-QAM signals transmitted on two or more MIMO spatial streams. A method includes estimating an initial solution yq for a received 2n-QAM symbol value b0b1 . . . bn-1, wherein all possible 2n-QAM symbol values are Gray-mapped constellation points; and performing an iteration for each hypothetical value of each bit position i of the initial solution yq, wherein each iteration comprises: determining a search center as: if ith bit of the initial solution equals the hypothetical value assumed for the current iteration, the initial solution yq; or if ith bit of the initial solution does not equal the hypothetical value assumed for the current iteration, a mirror constellation point yqc to the initial solution yq; and searching outward from the determined search center for candidate constellation points.
    Type: Application
    Filed: March 25, 2014
    Publication date: April 30, 2015
    Inventor: Fei TONG
  • Patent number: 9020062
    Abstract: Systems and methods are provided for decoding signal vectors in multiple-input multiple-output (MIMO) systems, where the receiver has received one or more signal vectors based on the same transmitted vector. The receiver linearizes each received signal vector using one or more zero-forcing, MMSE, or other suitable linear equalizers. The components of the equalized signal vectors may be combined using maximum-ratio combining to form the components of a combined equalized signal vector. The components of the combined equalized signal vector may then be decoded individually using a linear decoder.
    Type: Grant
    Filed: April 24, 2014
    Date of Patent: April 28, 2015
    Assignee: Marvell World Trade Ltd.
    Inventors: Jungwon Lee, Woong Jun Jang, Hui-Ling Lou
  • Patent number: 9008245
    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: December 12, 2012
    Date of Patent: April 14, 2015
    Assignee: Marvell International Ltd.
    Inventor: Jungwon Lee
  • Patent number: 9008242
    Abstract: A receiver system and method for recovering information from a symbol data sequence Y. The symbol data sequence Y corresponds to a symbol data sequence X that is transmitted onto the channel by a transmitter. The symbol data sequence X is generated by the transmitter based on associated information bits. At the receiver, a set of two or more processors operate in parallel on two or more overlapping subsequences of the symbol data sequence Y, where each of the two or more overlapping subsequences of the symbol data sequence Y corresponds to a respective portion of a trellis. The trellis describes redundancy in the symbol data sequence Y. The action of operating in parallel generates soft estimates for the associated information bits. The soft estimates are useable to form a receive message corresponding to the associated information bits.
    Type: Grant
    Filed: May 8, 2014
    Date of Patent: April 14, 2015
    Assignee: Coherent Logix, Incorporated
    Inventors: David B. Drumm, James P. Golab, Jan D. Garmany, Kevin L. Shelby, Michael B. Doerr
  • Patent number: 9008240
    Abstract: This invention is related to a low-complexity MIMO detector in a wireless communication system with near optimal performance. An initial symbol estimation is performed for a received symbol vector. The soft information of the received symbol vector can be more accurately calculated using every candidate symbol vector of a combined set of candidate symbol vectors, wherein the combined set is generated based on the initial estimation. By combining aspects of both the linear detection and the ML detection, the complexity of the proposed detector becomes orders of magnitude lower than that of a ML detector, but the performance is very close to that of an ML detector.
    Type: Grant
    Filed: December 31, 2013
    Date of Patent: April 14, 2015
    Assignee: Cambridge Silicon Radio Limited
    Inventors: Hong Wan, Fei Tong, Erik Lindskog
  • Patent number: 9008241
    Abstract: Methods, apparatuses, and systems are provided for generating a candidate search set for ML detection of 2n-QAM signals transmitted on two or more MIMO spatial streams. A method includes estimating an initial solution yq for a received 2n-QAM symbol value b0b1 . . . bn-1, wherein all possible 2n-QAM symbol values are Gray-mapped constellation points; and performing an iteration for each hypothetical value of each bit position i of the initial solution yq, wherein each iteration comprises: determining a search center as: if ith bit of the initial solution equals the hypothetical value assumed for the current iteration, the initial solution yq; or if ith bit of the initial solution does not equal the hypothetical value assumed for the current iteration, a mirror constellation point yqc to the initial solution yq; and searching outward from the determined search center for candidate constellation points.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: April 14, 2015
    Assignee: Samsung Electronics Co., Ltd
    Inventor: Fei Tong
  • Patent number: 9001879
    Abstract: Some demonstrative embodiments include devices, systems and/or methods of beam selection for beamformed communication. For example, an apparatus may include a controller to control a plurality of antenna subarrays to form a plurality of directional beams for communicating a beamformed diversity wireless transmission over a plurality of selected directional links, which are selected based on at least one predefined selection metric.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: April 7, 2015
    Assignee: Intel Corporation
    Inventors: Alexander Alexandrovich Maltsev, Andrey Pudeyev, Vladim S. Sergeyev, Ali S. Sadri, Carlos Cordeiro, Alexei Vladimirovich Davydov
  • Patent number: 9001913
    Abstract: A method implemented in a multicarrier transmission system, the method comprising generating a plurality of constellation points by using one or more constellation mappers to map a plurality of special data sequences for an idle data transmission unit (IDTU), wherein the plurality of special data sequences are computed prior to the mapping such that the plurality of constellation points are essentially inner constellation points, wherein each of the inner constellation points resides in a constellation diagram that corresponds to one of a plurality of subcarriers used by the IDTU, and wherein the constellation diagram comprises a number of inner constellation points and a number of outer constellation points, with the inner constellation points being closer from an origin of the constellation diagram than the outer constellation points, and transmitting the plurality of constellation points.
    Type: Grant
    Filed: September 5, 2013
    Date of Patent: April 7, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Ruxiang Wang, Guozhu Long, Yan Zhang, Amir H. Fazlollahi
  • Patent number: 8995581
    Abstract: Provided are a soft demapping apparatus and method that may cancel interference included in a rotated quadrature amplitude modulation (QAM) signal, using at least one interference cancellation unit, and may perform one-dimensional (1D) soft demapping of the interference-cancelled rotated QAM signal.
    Type: Grant
    Filed: May 10, 2012
    Date of Patent: March 31, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Kyeong Yeon Kim, Ki Taek Bae, Ho Yang
  • Patent number: 8989314
    Abstract: A computer-readable medium stores instructions causing one or more processors to demodulate a received signal including a plurality of user signals. Respective user data in each of at least some of the plurality of user signals is encoded with a respective finite state machine encoder having a respective number of states Si, wherein i=1, 2, . . . , N, N being the number of users, and wherein at least a first user signal and a second user signal are encoded independently of each other. The instructions cause the processor(s) to calculate distances between transmit symbols in the received signal and an expected joint symbol value, and jointly decode, with a finite state machine decoder, user data in the demodulated received signal, including at least first user data corresponding to the first user signal, based on the calculated distances. The finite state machine decoder has S1*S2* . . . *SN states.
    Type: Grant
    Filed: March 17, 2014
    Date of Patent: March 24, 2015
    Assignee: Marvell International Ltd.
    Inventors: Jungwon Lee, Jihwan P. Choi
  • Patent number: 8989284
    Abstract: A method and system for transitioning a communication circuit to a low-power state are disclosed. Where a first device and a second device communicate over a communication link, the first device may initiate a transition from an active state to a low-power state to conserve energy. A symbol may be encoded by the first device in data and transmitted to the second device. The first device may deactivate one or more components when entering the low-power state. Additionally, responsive to receiving and decoding the symbol, the second device may deactivate one or more components when entering the low-power state. In this manner, energy consumption of one or more components can be reduced and a low-power state may be entered to conserve energy.
    Type: Grant
    Filed: July 1, 2011
    Date of Patent: March 24, 2015
    Assignee: Altera Corporation
    Inventors: Divya Vijayaraghavan, Chong H. Lee
  • Patent number: 8982976
    Abstract: System and method embodiments are provided for Trellis Coded Quantization (TCQ) based channel feedback. The embodiments provide full channel state information with a short feedback size to a scheduler in order for the scheduler to apply advanced beamforming schemes, such as those designed in non-linear precoder methods. In an embodiment, a method in a station for providing channel feedback to a transmission point (TP) in a wireless system includes receiving a signal from the TP; estimating channel parameters for the signal; applying a TCQ scheme to the estimated channel parameters to map the channel estimate parameters to trellis codes; and transmitting full channel state information to the TP, wherein the full channel state information comprises output of a Viterbi algorithm (VA) corresponding to the trellis codes.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: March 17, 2015
    Assignee: FutureWei Technologies, Inc.
    Inventors: Junghoon Suh, Osama Aboul-Magd
  • Patent number: 8981908
    Abstract: Systems and methods for decoding data transmitted by RFID tags are disclosed. One embodiment of the invention includes an analyzer and equalizer configured to filter an input signal, an estimation block configured to obtain a baseband representation of the modulated data signal by mixing the filtered input signal with the carrier wave, and a coherent detector configured to perform phase and timing recovery on the modulated data signal in the presence of noise and to determine a sequence of data symbols.
    Type: Grant
    Filed: October 7, 2013
    Date of Patent: March 17, 2015
    Assignee: Mojix, Inc.
    Inventor: Ramin Sadr
  • Patent number: 8976911
    Abstract: A method and system for a sequence estimation in a receiver, such as for use when receiving a sample of a received inter-symbol correlated (ISC) signal corresponding to a transmitted vector of L symbols, with L being a integer greater than 1, and with symbol L being a most-recent symbol and symbol 1 being least recent symbol of the vector. A plurality of candidate vectors may be generated, wherein element L?m of each candidate vector holding one of a plurality of possible values of the symbol L?m, with m is an integer greater than or equal to 1, and elements L?m+1 through L of each candidate vectors holding determined filler values. A plurality of metrics may be generated based on the plurality of candidate vectors, and based on the generated plurality of metrics, a best one of the possible values of the symbol L?m may be selected.
    Type: Grant
    Filed: December 9, 2013
    Date of Patent: March 10, 2015
    Assignee: MagnaCom Ltd.
    Inventor: Amir Eliaz
  • Patent number: 8976909
    Abstract: A non-linear detector for detecting signals with signal-dependent noise is disclosed. The detector may choose a data sequence that maximizes the conditional probability of detecting the channel data. Since the channel may be time-varying and the precise channel characteristics may be unknown, the detector may adapt one or more branch metric parameters before sending the parameters to a loading block. In the loading block, the branch metric parameters may be normalized and part of the branch metric may be pre-computed to reduce the complexity of the detector. The loading block may then provide the branch metric parameters and any pre-computation to the detector. The detector may then calculate the branch metric associated with the input signal and output the channel data.
    Type: Grant
    Filed: May 23, 2013
    Date of Patent: March 10, 2015
    Assignee: Marvell International Ltd.
    Inventors: Hongxin Song, Seo-How Low, Panu Chaichanavong, Zining Wu
  • Patent number: 8972836
    Abstract: A receiver receives an inter-symbol correlated (ISC) signal with information symbols and a corresponding parity symbol. Values of information symbols are estimated utilizing parity samples that are generated from the parity symbols. One or more maximum likelihood (ML) decoding metrics are generated for the information symbols. One or more estimations are generated for the information symbols based on the one or more ML decoding metrics. A parity metric is generated for each of the one or more generated estimations of the information symbols. The parity metric is generated by summing a plurality of values of one of the generated estimations to generate a sum, and wrapping the sum to obtain a parity check value that is within the boundaries of a symbol constellation utilized in generating the information symbols.
    Type: Grant
    Filed: October 18, 2013
    Date of Patent: March 3, 2015
    Assignee: MagnaCom Ltd.
    Inventor: Amir Eliaz
  • Patent number: 8971382
    Abstract: A code generating apparatus, demodulation reference signal generating apparatus, and methods thereof. The demodulation reference signal generator includes generating a non-correlation sequence for RS of a first resource block; spreading spectrums of elements in the non-correlation sequence for RS to be mapped to a first frequency resource of the first resource block, by using a first group of codes; second spreading spectrums of elements in the non-correlation sequence for RS to be mapped to a second frequency resource of the first resource block, by using a second group of Codes; the first and second frequency resources are adjacent frequency resources in frequency resource elements used for RS transmission in the first resource block, and the first and second groups of Codes are mirrors in column to each other; and mapping the spectrum-spread elements to the first and second frequency resources, respectively.
    Type: Grant
    Filed: June 19, 2014
    Date of Patent: March 3, 2015
    Assignee: Fujitsu Limited
    Inventors: Yi Wang, Yuantao Zhang, Hua Zhou, Jianming Wu
  • Patent number: 8971242
    Abstract: A method for supporting Hybrid Automatic Repeat Request (HARQ) transmission during component carrier (CC) reallocation. The method includes starting a HARQ process using a first CC, allocating a second CC, mapping the HARQ process from the first CC to the second CC, and transmitting remaining HARQ data associated with the HARQ process using the second CC. Also included is a method for supporting HARQ transmission during CC reallocation comprising starting a HARQ process using a first CC, determining to allocate a second CC, waiting until completion of the HARQ process using the first CC before allocating the second CC, and beginning another HARQ process on the second CC. Included is a method comprising starting a HARQ process using a first CC, allocating a second CC, discontinuing transmission using the first CC before completion of the HARQ process, and restarting new data using the second CC.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: March 3, 2015
    Assignee: BlackBerry Limited
    Inventors: Zhijun Cai, Yi Yu
  • Publication number: 20150055722
    Abstract: A receiver may be operable to generate estimates of transmitted symbols using a sequence estimation process that may incorporate a non-linear model. The non-linear model may be adapted by the receiver based on particular communication information that may be indicative of non-linearity experienced by the transmitted symbols. The receiver may generate a reconstructed signal from the estimates of the transmitted symbols. The receiver may adapt the non-linear model based on values of an error signal generated from the reconstructed signal, and the values of the error signal may be generated from a portion of the generated estimates that may correspond to known symbols and/or information symbols. The values of the error signal corresponding to the known symbols may be given more weight in an adaptation algorithm, and the values of the error signal corresponding to the information symbols may be given less weight in the adaptation algorithm.
    Type: Application
    Filed: August 29, 2014
    Publication date: February 26, 2015
    Inventor: Amir Eliaz
  • Patent number: 8964871
    Abstract: A method for operating a receiver having multiple receive antennas to process a signal from a first affiliated transmitter and align interference from a second interfering transmitter includes providing a codebook of predefined matrices. Each predefined matrix has an identifier associated therewith. A first channel matrix and a second channel matrix are assembled for the first and the second transmitters. An equivalent direct channel matrix is determined from the first and second channel matrices, and predetermined reference vectors are selected from a plurality of predetermined vectors. A predefined matrix is selected from the codebook based upon the equivalent direct channel matrix and an identifier for the predefined matrix is fed back to the first transmitter. A signal is received and decoded using a combining matrix derived from the predetermined reference vectors and an inverse of the second channel matrix, thereby reducing interference from the interfering transmitters.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: February 24, 2015
    Assignee: BlackBerry Limited
    Inventors: Amin Mobasher, Alireza Bayesteh
  • Patent number: 8958505
    Abstract: The present invention is directed to reduction of operation amount of likelihood calculation (LLR calculation) in a communication apparatus for performing communications using an extended mapping in which a plurality of bit sequences are assigned to a single symbol point. A receiving unit receives a signal which is transmitted from a transmitting unit by using the extended mapping. A repetition process unit decodes the received signal from the receiving unit by calculating an LLR of the received signal and performing a repetition process. In this case, the LLR is calculated for every bit using a MAX-LOG approximation and a thus-derived approximation formula is multiplied by weighting factors corresponding to proportions of “0” and “1” in each bit assigned to a symbol point closest to the received signal.
    Type: Grant
    Filed: July 26, 2013
    Date of Patent: February 17, 2015
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Satoru Ejima, Takehiko Kobayashi, Keat Beng Toh
  • Patent number: 8953667
    Abstract: A method of operation of a communication system includes: calculating a shift distance of a received signal having a distortion; calculating an approximate likelihood of the received signal matching a transmitted signal from the shift distance; determining a bias factor from the distortion; and selecting a determined modulation maximizing a combination of the approximate likelihood and the bias factor for communicating with a device.
    Type: Grant
    Filed: January 15, 2014
    Date of Patent: February 10, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Dongwoon Bai, Jungwon Lee, Sungsoo Kim, Jung Hyun Bae, Jooyeol Yang, Inyup Kang
  • Patent number: 8953702
    Abstract: A process selects a Precoding Matrix Index (PMI) in a Multiple In Multiple Out (MIMO) receiver used in a wireless communications system including a base station communicating with User Equipments (UE) through a downlink and uplink channel. The base station applies a precoding on the transmit symbol vector based on a matrix selected from a set of predefined matrices and identified by a PMI index computed by the UE and forwarded to the base station via the uplink. The process includes estimating the MIMO channel matrix H of a given set of resources blocks comprising received symbol vectors, estimating the variance ?2 of the additive noise (AWGN), and computing for each particular matrix comprised within the set of predefined matrices a cost function representative of the orthogonality of the matrix MIMO channel matrix H.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: February 10, 2015
    Assignee: St-Ericsson SA
    Inventors: Sébastien Aubert, Andrea Ancora
  • Patent number: 8948283
    Abstract: In a method for generating a null data packet (NDP) sounding packet for transmission via a communication channel, a signal field and one or more long training fields are generated. The signal field and the long training fields are modulated using a plurality of orthogonal frequency division multiplexing (OFDM) symbols. Symbol duration of each OFDM symbol of the plurality of OFDM symbols is at least 8 ?s. The NDP sounding packet is generated to include the plurality of OFDM symbols. The NDP sounding packet omits a data payload portion.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: February 3, 2015
    Assignee: Marvell World Trade Ltd.
    Inventor: Hongyuan Zhang
  • Patent number: 8948318
    Abstract: An exemplary embodiment of the present invention provides an incremental lattice reduction method comprising: receiving an input signal at a plurality of input terminals; evaluating a reliability assessment condition using a primary symbol vector estimate of at least a portion of the input signal; terminating the incremental lattice reduction method if the reliability assessment condition is satisfied; and if the reliability assessment condition is not satisfied, performing at least one iteration of a lattice reduction detection sub-method to obtain a secondary symbol vector estimate.
    Type: Grant
    Filed: December 14, 2011
    Date of Patent: February 3, 2015
    Assignee: Georgia Tech Research Corporation
    Inventors: Brian Gestner, David Verl Anderson, Xiaoli Ma
  • Patent number: 8948298
    Abstract: Disclosed is a multiple-input multiple-output (MIMO) system including a transmitting end and a receiving end, wherein the transmitting end includes: a hierarchical codebook in which at least one base codebook is designated as the upper matrix and a child codebook generated based on a chordal distance between respective codewords configuring the base codebook is designated as the lower matrix; a scheduler configured to receive channel state information from the receiving end and select precoding matrices from the hierarchical codebook based on the channel state information; and a precoder configured to apply the precoding matrices selected in the scheduler to data to be transmitted to the receiving end and transmit the selected precoding matrices through a plurality of antennas.
    Type: Grant
    Filed: March 3, 2012
    Date of Patent: February 3, 2015
    Assignee: Seoul National University Industry Foundation
    Inventors: Jung Woo Lee, Kyeong Jun Ko, Sung Kyu Jung
  • Patent number: 8942326
    Abstract: The disclosure provides a channel decoding method and a tail biting convolutional decoder. The method comprises: the tail biting convolutional decoder performs add-compare-select processing on metric values of 2N states according to input data to be decoded and N zeros input after the data to obtain final cumulative metric values of the 2N states, and stores selection result of add-compare-select processing, wherein N is the constraint length of tail biting convolutional coding; the tail biting convolutional decoder starts to backtrack from one state of the 2N states according to the selection result to obtain intermediate decoding result after the add-compare-select processing is finished; the tail biting convolutional decoder outputs the bits except the last N bits of the intermediate decoding result as decoded result of the data to be decoded. The tail biting convolutional decoder comprises an add-compare-select module, a backtracking module and an outputting module.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: January 27, 2015
    Assignee: ZTE Corporation
    Inventor: Fanping Du
  • Patent number: 8941472
    Abstract: RFID data signals from RFID tags may be recovered by determining the probabilities of transitions between data states between a series of a pairs of signal samples using a set of predetermined probabilities related to data, timing, baud rate and/or phase variables affecting the received signal and processing those determined probabilities to determine the sequence of such transitions that has the highest probability of occurrence. A second set of predetermined probabilities related to transitions in the opposite direction may be used to sequence in a reverse direction. The determination of the sequence representing the RFID tag data may be iterated in both directions until further iterations do not change the determined probabilities.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: January 27, 2015
    Assignee: Mojix, Inc.
    Inventor: Ramin Sadr
  • Patent number: 8942306
    Abstract: A method selects a codebook for transmit beamforming. The method constructs an estimated channel matrix based on a codebook, selects a channel submatrix from the estimated channel matrix, calculates a selection matrix from the channel submatrix; and assigns a steering matrix based on the selection matrix. The method may construct an estimated channel matrix, select a channel submatrix, and calculate a selection matrix for each of multiple codebooks, then select an optimal codebook. The steering matrix is assigned based on the optimal codebook. The steering matrix may be used in steering a transmitted packet. The method may also calculate a post-MIMO equalizer signal-to-noise ratio for a data stream, based on the estimated channel matrix and the selected codebook. A related system is also disclosed. Other embodiments are provided, and each of the embodiments described herein can be used alone or in combination with one another.
    Type: Grant
    Filed: May 9, 2013
    Date of Patent: January 27, 2015
    Assignee: Marvell World Trade Ltd.
    Inventors: Hongyuan Zhang, Rohit U. Nabar
  • Patent number: 8938033
    Abstract: A method and system for offline processing alert messages (AR) on a digital radio broadcast receiver is described. A digital radio broadcast signal is received at the digital radio broadcast receiver. AR receivers will constantly look for AR alerts at a periodic interval by monitoring the station information service (SIS) on Primary IBOC Data Service (PIDS) channel to maximize the battery life at the same time achieving a reasonable latency in receiving AR alerts.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: January 20, 2015
    Assignee: Intel Corporation
    Inventors: Dongsheng Bi, Binuraj K. Ravindran
  • Patent number: RE45506
    Abstract: An enhanced VSB receiver includes a tuner which tunes an RF signal and converts it into an IF signal, an IF mixer which converts the IF signal into a baseband signal, and a demodulator which demodulates the baseband signal into a VSB signal. The enhanced VSB receiver further includes a map recovery unit which recovers VSB map information of the VSB signal, an enhanced equalizer for compensating channel distortion of the VSB signal and outputting an equalized symbol, and an enhanced Viterbi decoder for estimating whether polarity inversion occurred during a symbol period of the equalized symbol and Viterbi-decoding the equalized symbol based on the polarity estimation.
    Type: Grant
    Filed: March 12, 2014
    Date of Patent: May 5, 2015
    Assignee: LG Electronics Inc.
    Inventors: In Hwan Choi, Kyong Won Kang