# Jun Zheng, San Diego US

## Jun Zheng, San Diego, CA US

Patent application number | Description | Published |
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20080233965 | METHOD AND SYSTEM FOR ADAPTIVE ALLOCATION OF FEEDBACK RESOURCES FOR CQI AND TRANSMIT PRE-CODING - Aspects of a method and system for adaptive allocation of feedback resources for CQI and transmit pre-coding may include assigning a bandwidth and a feedback period to one or more CQI reporting units and a bandwidth and a feedback period to one or more PMI reporting units. One or more feedback messages may be generated based at least on channel state information associated with the bandwidth and the feedback period assigned to the one or more CQI reporting units and with the bandwidth and the feedback period assigned to the one or more PMI reporting units. The bandwidth and the feedback period of the CQI reporting units and/or the PMI reporting units may be adjusted dynamically and/or adaptively. Based on the channel state information or as a function of a feedback rate, the bandwidth and/or the feedback period may be assigned. | 09-25-2008 |

20080268862 | METHOD AND SYSTEM FOR BEST-M CQI FEEDBACK TOGETHER WITH PMI FEEDBACK - Aspects of a method and system for best-M CQI feedback together with PMI feedback may include generating a plurality of feedback messages, which may be communicated from a mobile station to a base station, wherein at least one of the generated plurality of feedback messages may be associated with each corresponding selected one of a plurality of Channel Quality Indicator (CQI) reporting units. The at least one of the generated feedback messages may comprise CQI information and Pre-coding Matrix Index (PMI) information, which may both be associated with the selected one of the plurality of CQI reporting units. At least one other of the generated plurality of feedback messages may comprise an aggregate CQI information, which is based on one or more of the plurality of CQI reporting units. | 10-30-2008 |

20080272953 | METHOD AND SYSTEM FOR CODEBOOK DESIGN FOR PRE-CODING TECHNIQUES - Aspects of a method and system for codebook design for pre-coding techniques may include generating one or more matrices whose matrix elements are from a constant amplitude signal constellation, wherein each of the one or more generated matrices may comprise one or more orthonormal columns, and one of the generated one or more matrices may be an identity matrix. Any two of the generated one or more matrices may be separated by at least a minimum pairwise distance. One or more pre-coding codebooks may be generated, each of which may comprise one or more codebook elements that may be of a same matrix rank. Each of the codebook elements may be generated from a subset of columns from one of the generated one or more matrices. A signal may be pre-coded for transmission using the one or more pre-coding codebooks. | 11-06-2008 |

20080273624 | METHOD AND SYSTEM FOR CQI/PMI FEEDBACK FOR PRECODED MIMO SYSTEMS UTILIZING DIFFERENTIAL CODEBOOKS - Aspects of a method and system for CQI/PMI feedback for precoded MIMO systems utilizing differential codebooks may include generating one or more feedback messages for one or more Channel Quality Indicator (CQI) reporting units based on at least channel state information associated with the one or more CQI reporting units. One or more differential feedback messages may be generated for one or more Pre-coding Matrix Index (PMI) reporting units based on at least channel state information associated with the one or more PMI reporting units, wherein the one or more PMI reporting units span a useable bandwidth. A bandwidth and a feedback period may be assigned to each of the one or more CQI reporting units and the one or more PMI reporting units to define the one or more CQI reporting units and the one or more PMI reporting units. | 11-06-2008 |

20090253381 | Method and System For Greedy User Group Selection With Range Reduction for FDD Multiuser MIMO Downlink Transmission With Finite-Rate Channel State Information Feedback - Aspects of a greedy search user group selection scheme with range reduction for FDD multiuser MIMO downlink transmission with finite-rate channel state information feedback are provided. The method may comprise receiving feedback information via a communication channel for a plurality of users in a frequency division duplex system. The system capacity may be maximized using the feedback information based on a signal from a single user within a reduced search range or based on the signal from the single user and at least one other signal from another user within a remaining portion of the search range. The feedback information may comprise quantized gain and/or direction of the channel state information of the users. | 10-08-2009 |

20090268833 | METHOD AND SYSTEM FOR PREDICTING CHANNEL QUALITY INDEX (CQI) VALUES FOR MAXIMUM LIKELIHOOD (ML) DETECTION IN A 2X2 MULTIPLE INPUT MULTIPLE OUTPUT (MIMO) WIRELESS SYSTEM - Aspects of a method and system for predicting CQI values for ML detection in a 2×2 MIMO system are presented. In one aspect of the system, a CQI value for a MIMO communication system may be computed based on a computed channel realization by reverse mapping the computed channel realization to a corresponding CQI value. Based on the computed CQI value, a coding rate may be selected. The coding rate may be selected from a lookup table, wherein the computed CQI value is utilized as an index to the lookup table. The reverse mapping may utilize a function, which is computed using radial basis function networks. In another aspect of the system, a joint mutual information value may be computed for the MIMO communication system. The joint mutual information value may be computed based on a Shannon mutual information value and a matched filter mutual information value. | 10-29-2009 |

20090268834 | METHOD AND SYSTEM FOR PREDICTING CHANNEL QUALITY INDEX (CQI) VALUES FOR MAXIMUM LIKELIHOOD (ML) DETECTION IN A KXK MULTIPLE INPUT MULTIPLE OUTPUT (MIMO) WIRELESS SYSTEM - Aspects of a method and system for predicting CQI values for ML detection in a K×K MIMO system are presented. In one aspect of the system, a CQI value for a K×K MIMO communication system may be computed by decomposing the K×K MIMO system into a series of 2×2 MIMO systems. For each 2×2 MIMO system a CQI value may be computed by reverse mapping a PER computed for the 2×2 MIMO system and an SNR value for a SISO communication system. By summing CQI values among the series of 2×2 MIMO systems a CQI value for the K×K MIMO system may be computed. Based on the computed CQI value for the K×K MIMO system, a coding rate may be selected. The selected coding rate may be selected to maximize a computed information throughput rate at a MIMO receiver that utilizes ML detection. | 10-29-2009 |

20110051828 | METHOD AND SYSTEM FOR AN EFFICIENT CHANNEL QUANTIZATION METHOD FOR MIMO PRE-CODING SYSTEMS - A method and system for processing communication signals is provided and may comprise, quantizing a channel estimate at a MIMO receiver onto a codebook based on a cost function, wherein the codebook comprises a plurality of unitary matrices. A codebook index may be fed back from the MIMO receiver to a MIMO transmitter, wherein the codebook index is associated with one of the plurality of unitary matrices that minimizes the cost function. The cost function may be minimized by choosing a smallest scalar cost from a plurality of scalar costs, wherein each one of the scalar costs is generated from one or more sums and one or more products of elements of a product matrix, and wherein the product matrix is generated from one of the plurality of unitary matrices, a matrix comprising the channel estimate, and their respective Hermitian Transposes. | 03-03-2011 |

20110164510 | METHOD AND SYSTEM FOR SELECTING A USER GROUP USING QUANTIZED CHANNEL STATE INFORMATION FEEDBACKS FROM MIMO CAPABLE MOBILE DEVICES - A mobile device estimates channel status information (CSI) for an associated single user downlink multiple-input multiple-output (MIMO) channel. The estimated CSI is quantized using a finite quantization resolution. The quantized CSI is communicated to the base station over a finite-rate feedback channel. Intended downlink data transmission is scheduled by the base station according to the transmitted CSI, and received by the mobile device, accordingly. The estimated CSI comprise generalized channel quality information such as channel capacity and channel direction. The base station selects a first user having a strongest channel capacity according to quantized CSI received from associated mobile devices. Beams orthogonal to a single user downlink MIMO channel of the selected first user are broadcasted. Quantized relative channel direction matrices and projected channel capacity are received from remaining mobile devices. A user having a strongest projected channel capacity is selected a second user for the user group. | 07-07-2011 |

20110164557 | METHOD AND SYSTEM FOR ITERATIVE DISCRETE FOURIER TRANSFORM (DFT) BASED CHANNEL ESTIMATION USING MINIMUM MEAN SQUARE ERROR (MMSE) TECHNIQUES - A method and system for iterative discrete Fourier transform (DFT) based channel estimation using minimum mean square error (MMSE) techniques are presented. Aspects of the method and system include a procedure for computing channel estimates in both the time domain and frequency domain (or mixed domain) using an iterative DFT method based on MMSE techniques. One aspect of the method and system may achieve low computational complexity and produce more accurate channel estimate values in low signal to noise ratio (SNR) regimes in comparison to conventional DFT-based channel estimation methods, which utilize least squares (LS) techniques. The method and system disclosed herein may be practiced in connection with a wide range of orthogonal frequency division multiplexing (OFDM) based systems, for example wireless local area networks (WLAN, for example IEEE 802.11 WLAN systems), and LTE systems. | 07-07-2011 |

20110164695 | METHOD AND SYSTEM FOR SELECTING A USER GROUP USING HYBRID-QUANTIZED CHANNEL DIRECTION INFORMATION FEEDBACKS FROM MIMO CAPABLE MOBILE DEVICES - A mobile device receives beams orthogonal to a single user downlink MIMO channel associated with a selected first user in a user group. The mobile device estimates relative channel direction information with respect to the received beams for an associated single user downlink MIMO channel. The estimated relative channel direction information is hybrid-quantized to generate a semi-orthogonal matrix transmitted to the base station over a finite-rate feedback link. The mobile device receives downlink data transmission according to the hybrid-quantized relative channel direction information. The base station receives multiple semi-orthogonal matrices from remaining mobile devices to generate a semi-orthogonal group for the selected first user. A mobile device having the strongest quantized projected channel capacity is selected from the generated semi-orthogonal group as a second user. Mutual channel capacity information for the selected first and second users is determined to schedule corresponding downlink data transmissions, accordingly. | 07-07-2011 |

20110165846 | METHOD AND SYSTEM FOR USING NON-UNIFORM CHANNEL QUANTIZATION FOR A FEEDBACK-BASED COMMUNICATION SYSTEM - A mobile device estimates channel state information (CSI) comprising, for example, CQI and/or SNR, for a downlink channel. The estimated CSI is non-uniformly quantized and transmitted to the base station over a finite-rate feedback channel. Different portions of the estimated CSI are quantized using different quantization step sizes, which are determined according to a performance metric function such as a channel capacity function of the estimated CSI. A quantization step size for a portion of the estimated CSI is increased if a low distribution probability is indicated by the portion of the estimated CSI. A quantization step size for a portion of the estimated CSI is decreased if a high distribution probability is indicated. The mobile device quantizes the estimated CSI using the determined quantization step sizes to transmit to the base station over the finite-rate feedback channel. Downlink data transmission is received according to the transmitted CSI. | 07-07-2011 |

20110200141 | METHOD AND SYSTEM FOR AN EFFICIENT CHANNEL QUANTIZATION METHOD FOR MIMO PRE-CODING SYSTEMS - A method and system for processing communication signals is provided and may comprise, minimizing a cost function in a MIMO pre-coding system by choosing a smallest scalar cost from a plurality of scalar costs, wherein each one of the scalar costs is generated from one or more sums and one or more products of elements of a product matrix, and wherein the product matrix is generated from one of the plurality of unitary matrices, a matrix comprising the channel estimate, and their respective Hermitian Transposes. The codebook is selected based on the minimized cost function. The channel estimate is quantized onto the selected codebook. | 08-18-2011 |

20110206161 | METHOD AND SYSTEM FOR A DELTA QUANTIZER FOR MIMO PRE-CODERS WITH FINITE RATE CHANNEL STATE INFORMATION FEEDBACK - A MIMO pre-coding system for a delta quantizer for MIMO pre-coders with finite rate channel state information feedback may include quantizing a change in channel state information in a MIMO pre-coding system onto a codebook, which comprises one or more unitary matrices, using a cost function. The codebook may be generated based on at least the channel state information. The channel state information may comprise a matrix V and the cost function f(A) may be defined by the following relationship: | 08-25-2011 |

20110211656 | METHOD AND SYSTEM FOR A DELTA QUANTIZER FOR MIMO PRE-CODERS WITH FINITE RATE CHANNEL STATE INFORMATION FEEDBACK - A delta quantizer for MIMO pre-coders with finite rate channel state information feedback may comprise partly quantizing a change in channel state information in a MIMO pre-coding system onto at least a first and a second codebook, each of which comprises one or more unitary matrices, using a cost function; and generating the at least first and second codebook based on at least the channel state information. The channel state information may be a matrix V and the cost function may be defined by the following relationship: | 09-01-2011 |

20110274196 | METHOD AND SYSTEM FOR CODEBOOK DESIGN OF MIMO PRE-CODERS WITH FINITE RATE CHANNEL STATE INFORMATION FEEDBACK - Channel state information in a multiple-input multiple-output (MIMO) pre-coding system is quantized onto a codebook, which comprises one or more unitary matrices, using a cost function. Voronoi regions are computed from the codebook. The codebook may be updated based on the computed Voronoi regions. The channel state information may comprise a matrix V. The cost function f(A) is defined by the following relationship: | 11-10-2011 |

20110305178 | Cyclic shift delay (CSD) short training field (STF) for orthogonal frequency division multiplexing (OFDM) signaling within multiple user, multiple access, and/or MIMO wireless communications - Cyclic shift delay (CSD) short training field (STF) for use within multiple user, multiple access, and/or MIMO wireless communications. Appropriately designed CSD STF is applied to communications in wireless communication systems thereby ensuring a minimized power error difference between respective portions of a packet transmitted therein. A first portion of the packet may be a short training field (STF) and a second portion of the packet may be a payload (e.g., a data portion). By applying such appropriately designed CSD STF to a packet, a wireless communication device that receives a signal corresponding to that packet need not perform extra or very significant backoff (e.g., with respect to a signal subsequent to automatic gain control (AGC) processing) thereby simplifying processing of that signal and potentially also reducing a total number of effective analog to digital converter (ADC) bits needed to represent a digitally sampled version of that signal. | 12-15-2011 |

20110305194 | Legacy cyclic shift delay (CSD) for orthogonal frequency division multiplexing (OFDM) signaling within multiple user, multiple access, and/or MIMO wireless communications - Legacy cyclic shift delay (CSD) for use within multiple user, multiple access, and/or MIMO wireless communications. Appropriately designed CSD is applied to communications in wireless communication systems thereby ensuring a minimized power error difference between respective portions of a packet transmitted therein. Such respective portions of the packet may be portions of the packet's preamble. For example, the first and second portions may be a legacy short training field (L-STF) and a very high throughput short training field (VHT-STF). By applying such appropriately designed CSD to a packet, a wireless communication device receiving a signal corresponding to that packet need not perform extra or very significant backoff (e.g., with respect to a signal subsequent to automatic gain control (AGC) processing) thereby simplifying signal processing and potentially also reducing a total number of effective analog to digital converter (ADC) bits needed to represent a digitally sampled version of that signal. | 12-15-2011 |

20120076223 | Method and System for an Alternating Delta Quantizer for Limited Feedback MIMO Pre-Coders - Aspects of a method and system for an alternating delta quantizer for limited feedback MIMO pre-coders may comprise quantizing a change in channel state information in a MIMO pre-coding system onto at least a first and a second codebook, each of which comprises one or more unitary matrices, using a cost function; feeding back, in an alternating manner, an index to an element of at least the first codebook or the second codebook, associated with the quantizing, from a receiver to a transmitter in said MIMO pre-coding system, and generating the at least first and second codebook based on at least the channel state information. The channel state information may be a matrix V and the cost function may be defined by the following relationship: | 03-29-2012 |

20120082128 | METHOD AND SYSTEM FOR ADAPTIVE ALLOCATION OF FEEDBACK RESOURCES FOR CQI AND TRANSMIT PRE-CODING - In transmit pre-coding, a bandwidth and a feedback period to one or more CQI reporting units and a bandwidth and a feedback period to one or more PMI reporting units are assigned, respectively. Sub-divisions in time and/or frequency corresponding to the assigned bandwidths and the assigned feedback periods are dynamically adjusted based at least on uplink channel state information corresponding to the bandwidth and the feedback period assigned to the CQI reporting units, and the bandwidth and the feedback period assigned to the PMI reporting units. One or more feedback messages are generated based at least on the channel state information over the adjusted sub-divisions in time and/or frequency corresponding to the CQI reporting units and to the PMI reporting units, respectively. The bandwidth and/or the feedback period may be assigned based on the channel state information or as a function of a feedback rate. | 04-05-2012 |

20120106668 | METHOD AND SYSTEM FOR AN ALTERNATING CHANNEL DELTA QUANTIZER FOR MIMO PRE-CODERS WITH FINITE RATE CHANNEL STATE INFORMATION FEEDBACK - Aspects of a method and system for an alternating channel delta quantizer for MIMO pre-coders with finite rate channel state information feedback may include quantizing a change in channel state information in a MIMO pre-coding system onto a codebook using a cost function and selecting the codebook from a set of codebooks; and generating the set of codebooks from a plurality of codebooks, where each may comprise one or more unitary matrices. The channel state information may be a matrix V that may be generated using Singular Value Decomposition (SVD) and/or Geometric Mean Decomposition (GMD). The selecting of the codebooks may be enabled by alternating between the elements of the set of codebooks. The cost function f(A) may be defined by the following relationship: | 05-03-2012 |

20120269123 | Preamble for use within single user, multiple user, multiple access, and/or MIMO wireless communications - Preamble for use within single user, multiple user, multiple access, and/or MIMO wireless communications. A selected preamble type is employed for use in generating a signal to be transmitted from one communication device to at least one other communication device. Depending upon a desired operational mode, as few as one preamble type, or two or more preamble types may be associated with a given operational mode. When operating in accordance with a given operational mode, a preamble type is selected from available preamble types of an operational mode. A preferred implementation may include two respective preamble types such that one preamble type is used for single user (SU) operation with transmit beamforming weights applied at the beginning of the packet or for open loop SU transmissions only, while the other preamble type, having an multiple user (MU) characteristic, is used for both SU beamforming and MU operations. | 10-25-2012 |

20120269125 | Short training field (STF) for use within single user, multiple user, multiple access, and/or MIMO wireless communications - Short training field (STF) for use within single user, multiple user, multiple access, and/or MIMO wireless communications. An STF design as is made such that the power associated with the tone indices at the edges of the STF design is relatively less than the power associated with the tone indices more centrally located within the STF design. Also, when multiple respective operational modes are supported (e.g., | 10-25-2012 |

20120269294 | Modulation code set (MCS) and LDPC (Low Density Parity Check) coding within multiple user, multiple access, and/or MIMO wireless communications - Modulation code set (MCS) and LDPC (Low Density Parity Check) coding within multiple user, multiple access, and/or MIMO wireless communications. Selective operation in accordance with different operational modes is performed. Operation within a first mode may correspond to that which is in full compliance with a given protocol, standard, and/or recommended practice, while operation within a second mode may correspond to that which provides additional/augmented capability and/or functionality with respect to that protocol, standard, and/or recommended practice. Operational modes selectivity may be made between proprietary and non-proprietary modes of operation. All available modulation coding sets (MCSs) may be in employed by providing such multi-mode operation. When operating within one of the operational modes (e.g., proprietary), a signal is generated to include an integer number of data bits per orthogonal frequency division multiplexing (OFDM) symbol using any desired operation (e.g., floor, ceiling, rounding, etc.). | 10-25-2012 |

20120281773 | Method and System for Best-M CQI Feedback Together with PMI Feedback - Aspects of a method and system for best-M CQI feedback together with PMI feedback may include generating a plurality of feedback messages, which may be communicated from a mobile station to a base station, wherein at least one of the generated plurality of feedback messages may be associated with each corresponding selected one of a plurality of Channel Quality Indicator (CQI) reporting units. The at least one of the generated feedback messages may comprise CQI information and Pre-coding Matrix Index (PMI) information, which may both be associated with the selected one of the plurality of CQI reporting units. At least one other of the generated plurality of feedback messages may comprise an aggregate CQI information, which is based on one or more of the plurality of CQI reporting units. | 11-08-2012 |

20130109324 | REVERSE CHANNEL ESTIMATION FOR RF TRANSCEIVER WITH BEAMFORMING ANTENNA | 05-02-2013 |

20130109448 | RF TRANSCEIVER WITH BEAMFORMING ANTENNA AND METHODS FOR USE THEREWITH | 05-02-2013 |

20130315169 | Peak to average power ratio (PAPR) reduction for repetition mode within single user, multiple user, multiple access, and/or MIMO wireless communications - Selective processing of one or more packets to be transmitted from a wireless communication device to another wireless communication device is effective to reduce the peak to average power ratio (PAPR) of the transmission. The one or more packets are transmitted via two or more sub-bands of an available transmission medium. The number of coefficients or factors within that sequence corresponds to the number of sub-bands via which the one or more packets are to be transmitted. Also, a phase ramp or time-domain cyclic shift may be added to one or more of the packets after having undergone multiplication by one of the coefficients or factors within the sequence. | 11-28-2013 |

20140160957 | CHANNEL STATE INFORMATION CALIBRATION - A dedicated calibration device may be utilized by a wireless transceiver device, such as a base station, to compute compensation matrices. The wireless transceiver device and the dedicated calibration device can exchange training sequence signals. Based on the exchanged training sequence signals, the wireless transceiver device and the dedicated calibration device can estimate overall baseband to baseband channel responses taking into account the amplitude and phase responses of the respective transmit and receive radio chains, and the wireless transceiver device can determine the compensation matrices. Furthermore, the wireless transceiver device can estimate a baseband-to-baseband uplink channel response relative to actual user equipment, approximate a downlink channel response using only one of the determined compensation matrices, and perform beamforming to the actual user equipment using the approximated downlink channel response. | 06-12-2014 |