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公开(公告)号：AT456199T
公开(公告)日：2010-02-15
申请号：AT05794158
申请日：2005-09-02
Applicant: QUALCOMM INC
Inventor： WALLACE MARK , MEDVEDEV IRINA , WALTON JAY
Abstract: A receiving entity obtains received symbols for a data transmission having at least one data symbol stream sent with space-time transmit diversity (STTD). The receiving entity derives an overall channel response matrix in accordance with the STTD encoding scheme used for the data transmission, derives a spatial filter matrix based on the overall channel response matrix, and performs spatial matched filtering on a vector of received symbols for each 2-symbol interval to obtain a vector of detected symbols for the 2-symbol interval. The receiving entity may perform post-processing (e.g., conjugation) on the detected symbols if needed. Alternatively, the receiving entity derives a spatial filter matrix based on an effective channel response matrix, performs spatial matched filtering on the received symbols for each symbol period to obtain detected symbols for that symbol period, and combines multiple estimates obtained for each data symbol sent with STTD.
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公开(公告)号：CA2711088A1
公开(公告)日：2009-08-06
申请号：CA2711088
申请日：2008-02-01
Applicant: QUALCOMM INC
Inventor： WALLACE MARK S , WALTON JAY RODNEY , MEDVEDEV IRINA
Abstract: A method for identifying a reference point in time in a wireless communication system includes: receiving a first repeated sequence of symbols; receiving a second repeated sequence of symbols; performing an autocorrelation between the first and second sequences of symbols; and identifying as the reference point in time an autocorrelation null between the first and second repeated sequences of symbols. Apparatus for identifying a reference point in time in a wireless communication system includes: means for receiving a first repeated sequence of symbols; means for receiving a second repeated sequence of symbols; means for performing an autocorrelation between the first and second sequences of symbols; and means for identifying as the reference point in time an autocorrelation null between the first and second repeated sequences of symbols.
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公开(公告)号：AU2002360839C1
公开(公告)日：2009-01-22
申请号：AU2002360839
申请日：2002-12-31
Applicant: QUALCOMM INC
Inventor： WALLACE MARK , MEDVEDEV IRINA , WALTON JAY ROD , KETCHUM JOHN W
Abstract: Techniques to schedule terminals for data transmission on the downlink and/or uplink in a MIMO-OFDM system based on the spatial and/or frequency "signatures" of the terminals. A scheduler forms one or more sets of terminals for possible (downlink or uplink) data transmission for each of a number of frequency bands. One or more subhypotheses may further be formed for each hypothesis, with each sub-hypothesis corresponding to (1) specific assignments of transmit antennas to the terminal(s) in the hypothesis (for the downlinks) or (2) a specific order for processing the uplink data transmissions from the terminal(s) (for the uplink). The performance of each sub-hypothesis is then evaluated (e.g., based on one or more performance metrics).; One sub-hypothesis is then selected for each frequency band based on the evaluated performance, and the one or more terminals in each selected sub-hypothesis are then scheduled for data transmission on the corresponding frequency band.
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公开(公告)号：AU2003213214B2
公开(公告)日：2008-10-02
申请号：AU2003213214
申请日：2003-02-19
Applicant: QUALCOMM INC
Inventor： MEDVEDEV IRINA , WALLACE MARK , WALTON JAY R
IPC: H04J99/00 , H04B7/005 , H04B7/04 , H04B7/06 , H04B7/08 , H04J11/00 , H04L1/00 , H04L1/06 , H04L27/26
Abstract: Techniques to transmit data on a number of transmission channels in a multi-channel communication system using multiple transmission schemes requiring less channel-state information (CSI). These schemes may include a partial-CSI transmission scheme that transmits a single data stream on each transmit antenna selected for use and a "beam-forming" transmission scheme that allocates all transmit power to a single transmission channel having the best performance. Each transmission scheme may provide good or near-optimum performance for a specific range of operating conditions (or operating SNRs). These multiple transmission schemes may then be combined in a piece-wise fashion to form a "multi-mode" transmission scheme that covers the full range of operating conditions supported by the MIMO system. The specific transmission scheme to be used for data transmission at any given moment would then be dependent on the specific operating condition experienced by the system at that moment.
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公开(公告)号：AT405040T
公开(公告)日：2008-08-15
申请号：AT03709260
申请日：2003-02-19
Applicant: QUALCOMM INC
Inventor： MEDVEDEV IRINA , WALTON JAY , WALLACE MARK
IPC: H04B7/06 , H04J99/00 , H04B7/005 , H04B7/04 , H04B7/08 , H04J11/00 , H04L1/00 , H04L1/06 , H04L27/26
Abstract: Techniques to transmit data on a number of transmission channels in a multi-channel communication system using multiple transmission schemes requiring less channel-state information (CSI). These schemes may include a partial-CSI transmission scheme that transmits a single data stream on each transmit antenna selected for use and a "beam-forming" transmission scheme that allocates all transmit power to a single transmission channel having the best performance. Each transmission scheme may provide good or near-optimum performance for a specific range of operating conditions (or operating SNRs). These multiple transmission schemes may then be combined in a piece-wise fashion to form a "multi-mode" transmission scheme that covers the full range of operating conditions supported by the MIMO system. The specific transmission scheme to be used for data transmission at any given moment would then be dependent on the specific operating condition experienced by the system at that moment.
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Patent Agency Ranking
公开(公告)号：AT400931T
公开(公告)日：2008-07-15
申请号：AT03709263
申请日：2003-02-19
Applicant: QUALCOMM INC
Inventor： MEDVEDEV IRINA , WALTON JAY R , KETCHUM JOHN W
Abstract: Techniques for controlling the transmit power for a number of data streams in a wireless multi-channel (e.g., MIMO) communication system. In one method, a number of received symbol streams are initially processed in accordance with a particular (e.g., CCMI, CCMISC, MMSE, or MMSE-SC) receiver processing technique to provide a number of detected data streams. The post-detection SNRs of the detected data streams are estimated, and each SNR that exceeds a setpoint is identified. This setpoint may correspond to (1) the SNR needed to achieve the maximum allowed spectral efficiency or (2) the target SNR needed to achieve a specified spectral efficiency. A new (or adjusted) transmit power for each detected data stream associated with a post-detection SNR that exceeds the setpoint is determined and used for the data stream. Different power control schemes are provided for different classes of receiver processing techniques with different characteristics.
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公开(公告)号：RU2328074C2
公开(公告)日：2008-06-27
申请号：RU2005108590
申请日：2003-08-19
Applicant: QUALCOMM INC
Inventor： MEDVEDEV IRINA , UOLTON DZHEJ ROD , KETCHUM DZHON U
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公开(公告)号：DE60316663D1
公开(公告)日：2007-11-15
申请号：DE60316663
申请日：2003-01-22
Applicant: QUALCOMM INC
Inventor： MEDVEDEV IRINA , WALTON JAY ROD , KETCHUM JOHN W
Abstract: Techniques to allocate the total transmit power to the transmission channels in a multi-channel communication system such that higher overall system spectral efficiency and/or other benefits may be achieved. The total transmit power may be initially allocated to the transmission channels based on a particular power allocation scheme (e.g., the water-filling scheme). The initial allocation may result in more power being allocated to some transmission channels than needed to achieve the required SNR (e.g., the SNR needed to achieve the maximum allowed data rate), which would then result in these transmission channels being operated in the saturation region. In such situations, the techniques reallocate the excess transmit power of transmission channels operated in the saturation region to other transmission channels operated below the saturation region. In this way, higher data rate may be achieved for the "poorer" transmission channels without sacrificing the performance of the "better" transmission channels.
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公开(公告)号：DE60310237D1
公开(公告)日：2007-01-18
申请号：DE60310237
申请日：2003-08-19
Applicant: QUALCOMM INC
Inventor： MEDVEDEV IRINA , WALTON ROD , KETCHUM W
Abstract: Techniques to perform selective channel inversion per eigenmode in a MIMO system to achieve high spectral efficiency while reducing complexity at both the transmitter and receiver are presented. The available transmission channels are arranged into a number of groups, where each group may include all transmission channels (or frequency bins) for a respective eigenmode of a MIMO channel. The total transmit power is allocated to the groups using a particular group power allocation scheme. Selective channel inversion is then performed independently for each group selected for use for data transmission. For each such group, one or more transmission channels in the group are selected for use, and a scaling factor is determined for each selected channel such that all selected channels for the group achieve similar received signal quality (e.g., received SNR).
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公开(公告)号：HK1078187A1
公开(公告)日：2006-03-03
申请号：HK05110089
申请日：2005-11-11
Applicant: QUALCOMM INC
Inventor： MEDVEDEV IRINA , WALTON JAY ROD , KETCHUM JOHN W
Abstract: Techniques to allocate the total transmit power to the transmission channels in a multi-channel communication system such that higher overall system spectral efficiency and/or other benefits may be achieved. The total transmit power may be initially allocated to the transmission channels based on a particular power allocation scheme (e.g., the water-filling scheme). The initial allocation may result in more power being allocated to some transmission channels than needed to achieve the required SNR (e.g., the SNR needed to achieve the maximum allowed data rate), which would then result in these transmission channels being operated in the saturation region. In such situations, the techniques reallocate the excess transmit power of transmission channels operated in the saturation region to other transmission channels operated below the saturation region. In this way, higher data rate may be achieved for the "poorer" transmission channels without sacrificing the performance of the "better" transmission channels.
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