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    MULTI-ANTENNA TRANSMISSION FOR SPATIAL DIVISION MULTIPLE ACCESS
    153.
    发明专利
    MULTI-ANTENNA TRANSMISSION FOR SPATIAL DIVISION MULTIPLE ACCESS 未知

    公开(公告)号：SG150536A1

    公开(公告)日：2009-03-30

    申请号：SG2009012113

    申请日：2004-11-12

    Applicant: QUALCOMM INC

    Inventor： WALTON J RODNEY ,  KETCHUM JOHN W ,  SMEE JOHN EDWARD ,  WALLACE MARK S ,  HOWARD STEVEN J

    IPC: H04B7/06 ,  H04J11/00 ,  H04J99/00 ,  H04L5/02 ,  H04Q7/36

    Abstract: MULTI-ANTENNA TRANSMISSION FOR SPATIAL DIVISION MULTIPLE ACCESS An uplink channel response matrix is obtained for each terminal and decomposed to obtain a steering vector used by the terminal to transmit on the uplink. An 'effective' uplink channel response vector is formed for each terminal based on its steering vector and its channel response matrix. Multiple sets of terminals are evaluated based on their effective channel response vectors to determine the best set (e.g., with highest overall throughput) for uplink transmission. Each selected terminal performs spatial processing on its data symbol stream with its steering vector and transmits its spatially processed data symbol stream to an access point. The multiple selected terminals simultaneously transmit their data symbol streams via their respective MIMO channels to the access point. The access point performs receiver spatial processing on its received symbol streams in accordance with a receiver spatial processing technique to recover the data symbol streams transmitted by the selected terminals.

    SYSTEMS AND METHODS FOR CHANNEL ESTIMATION IN WIRELESS COMMUNICATION SYSTEM
    154.
    发明专利
    SYSTEMS AND METHODS FOR CHANNEL ESTIMATION IN WIRELESS COMMUNICATION SYSTEM 未知

    公开(公告)号：CA2790201A1

    公开(公告)日：2008-07-10

    申请号：CA2790201

    申请日：2008-01-02

    Applicant: QUALCOMM INC

    Inventor： BJERKE BJORN ,  HOWARD STEVEN J

    IPC: H04L69/14 ,  H04W24/00 ,  H04B7/02

    Abstract: Disclosed herein are methods and apparatus for enhancing the estimation of channel response in a wireless communication system. An apparatus (and associated method) for optimizing channel estimation in a communication system includes a receiving antenna; a receiver adapted to receive a signal from the receiving antenna; an initial channel estimator module adapted to select a selected channel from among one or more channels in the communication system and to determine, for the selected channel, an initial channel estimate based upon the received signal; a transformation module adapted to transform the initial channel estimate into an initial impulse response estimate comprising a sequence of samples; a filtering module adapted to select a sub-sequence of samples from the sequence of samples and generate a truncated initial impulse response estimate by setting to zero the samples in the initial impulse response estimate that are not in the selected sub-sequence of samples; and a maximum likelihood channel estimating module adapted to compute a time domain weighted impulse response estimate using the truncated time domain impulse response estimate for the selected channel and to compute a maximum likelihood channel estimate for the selected channel by transforming the time domain weighted impulse response estimate into the frequency domain.

    156.
    发明专利
    未知

    公开(公告)号：BRPI0512808A

    公开(公告)日：2008-04-08

    申请号：BRPI0512808

    申请日：2005-06-27

    Applicant: QUALCOMM INC

    Inventor： WALLACE MARK S ,  WALTON JAY RODNEY ,  HOWARD STEVEN J

    IPC: H04B7/08 ,  H04J99/00

    Abstract: Techniques for efficiently computing spatial filter matrices are described. The channel response matrices for a MIMO channel may be highly correlated if the channel is relatively static over a range of transmission spans. In this case, an initial spatial filter matrix may be derived based on one channel response matrix, and a spatial filter matrix for each transmission span may be computed based on the initial spatial filter matrix and a steering matrix used for that transmission span. The channel response matrices may be partially correlated if the MIMO channel is not static but does not change abruptly. In this case, a spatial filter matrix may be derived for one transmission span l and used to derive an initial spatial filter matrix for another transmission span m. A spatial filter matrix for transmission span m may be computed based on the initial spatial filter matrix, e.g., using an iterative procedure.

    PHASE CORRECTION FOR OFDM AND MIMO TRANSMISSIONS
    158.
    发明专利
    PHASE CORRECTION FOR OFDM AND MIMO TRANSMISSIONS 未知

    公开(公告)号：CA2844937A1

    公开(公告)日：2007-11-29

    申请号：CA2844937

    申请日：2007-05-22

    Applicant: QUALCOMM INC

    Inventor： WALTON J RODNEY ,  WALLACE MARK S ,  MEDVEDEV IRINA ,  HOWARD STEVEN J

    IPC: H04B7/01 ,  H04B1/76 ,  H04W56/00

    Abstract: Techniques for performing phase correction for wireless communication are described. Received pilot symbols and received data symbols may be obtained from an orthogonal frequency division multiplexing (OFDM) and/or multiple-input multiple-output (MIMO) transmission. First phase information is obtained based upon the received pilot symbols. Second phase information is obtained based upon the received data symbols. The phase of the received data symbols is corrected based upon the first and second phase information (directly and/or indirectly). For example, the phase of the received data symbols may be corrected based upon the first phase information, detection may be performed on the phase corrected data symbols to obtain estimated data symbols, the second phase information may be obtained based upon the estimated data symbols, and the phase of the estimated data symbols may be corrected based upon the second phase information. The phase correction may also be performed in other manners.

    SINGLE-BURST ACQUISITION FOR WIRELESS COMMUNICATION SYSTEM
    159.
    发明专利
    SINGLE-BURST ACQUISITION FOR WIRELESS COMMUNICATION SYSTEM 未知

    公开(公告)号：CA2777890A1

    公开(公告)日：2007-11-29

    申请号：CA2777890

    申请日：2007-05-22

    Applicant: QUALCOMM INC

    Inventor： WALLACE MARK S ,  KETCHUM JOHN W ,  WALTON JAY RODNEY ,  HOWARD STEVEN J

    IPC: H04L7/02 ,  H04W56/00 ,  H04W80/02

    Abstract: Techniques for performing acquisition of packets are described. First detection values may be determined based on a first plurality of samples, e.g., by performing delay-multiply-integrate on the samples. Power values may be determined based on the first plurality of samples, e.g., by performing multiply-integrate on the samples. The first detection values may be averaged to obtain average detection values. The power values may also be averaged to obtain average power values. Whether a packet is presence may be determined based on the average detection values and the average power values. Second detection values may be determined based on a second plurality of samples. The start of the packet may be determined based on the first and second detection values. A third detection value may be determined based on a third plurality of samples. Frequency error of the packet may be estimated based on the first and third detection values.

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