公开(公告)号：EP1532762B1

公开(公告)日：2006-12-06

申请号：EP03791732.5

申请日：2003-08-19

申请人： QUALCOMM INCORPORATED

发明人： MEDVEDEV, Irina ,  WALTON, Jay, Rod ,  KETCHUM, John, W.

IPC分类号： H04L1/06 ,  H04B7/005

CPC分类号： H04W52/346 ,  H04B7/0413 ,  H04B7/0439 ,  H04L1/0003 ,  H04L1/0009 ,  H04L1/0041 ,  H04L1/0068 ,  H04L1/0071 ,  H04W52/42

摘要： 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).

公开(公告)号：EP1695500A1

公开(公告)日：2006-08-30

申请号：EP04813896.0

申请日：2004-12-13

申请人： Qualcomm, Incorporated

发明人： WALTON, Jay, Rodney ,  KETCHUM, John, W. ,  WALLACE, Mark, S. ,  HOWARD, Steven, J.

IPC分类号： H04L25/03 ,  H04B7/04

CPC分类号： H04L25/03866 ,  H04B7/043 ,  H04B7/0615 ,  H04B7/0669 ,  H04B7/0678 ,  H04B7/068 ,  H04B7/12 ,  H04L5/0007 ,  H04L25/0204 ,  H04L25/0224 ,  H04W52/42

摘要： An access point in a multi-antenna system broadcasts data using spatial spreading to randomize an 'effective' channel observed by each user terminal for each block of data symbols broadcast by the access point. At the access point, data is coded, interleaved, and modulated to obtain N D data symbol blocks to be broadcast in N M transmission spans, where N D ‰¥1 and N M >1. The N D data symbol blocks are partitioned into N M data symbol subblocks, one subblock for each transmission span. A steering matrix is selected (e.g., in a deterministic or pseudo-random manner from among a set of L steering matrices) for each subblock. Each data symbol subblock is spatially processed with the steering matrix selected for that subblock to obtain transmit symbols, which are further processed and broadcast via N T transmit antennas and in one transmission span to user terminals within a broadcast coverage area.

公开(公告)号：EP1680897A1

公开(公告)日：2006-07-19

申请号：EP04795249.4

申请日：2004-10-15

申请人： QUALCOMM INCORPORATED

发明人： KETCHUM, John, W. ,  WALLACE, Mark, S. ,  WALTON, Rodney, J. ,  NANDA, Sanjiv

IPC分类号： H04L12/56 ,  H04L29/06

CPC分类号： H04L29/06 ,  H04L69/32 ,  H04L69/324 ,  H04L69/325

摘要： Embodiments addressing MAC processing for efficient use of high throughput systems are disclosed. In one aspect, an apparatus comprises a first layer for receiving one or more packets from one or more data flows and for generating one or more first layer Protocol Data Units (PDUs) from the one or more packets. In another aspect, a second layer is deployed for generating one or more MAC frames based on the one or more MAC layer PDUs. In another aspect, a MAC frame is deployed for transmitting one or more MAC layer PDUs. The MAC frame may comprise a control channel for transmitting one or more allocations. The MAC frame may comprise one or more traffic segments in accordance with allocations.

公开(公告)号：EP1576733A1

公开(公告)日：2005-09-21

申请号：EP03783405.8

申请日：2003-11-12

申请人： QUALCOMM INCORPORATED

发明人： BJERKE, Bjorn ,  KETCHUM, John, W. ,  SINDHUSHAYANA, Nagabhushana ,  WALTON, Jay, Rod

IPC分类号： H03M13/00

CPC分类号： H04L1/0057 ,  H03M13/11 ,  H03M13/6393

摘要： Method and apparatus for generating codewords with variable length and redundancy from a single Low-Density Parity-Check (LDPC) code with variable length input words. A mother code for encoding data words is generated based on a parity-check matrix, wherein the mother code is adjusted to reflect the size of the data word to be encoded. A generator matrix applies the mother code to data words to produce codewords for transmission. In one embodiment, a reduction criteria is determined and the size of the generator matrix reduced in response. The corresponding parity-check matrix is applied at the receiver for decoding the received codeword.

公开(公告)号：EP1570616A1

公开(公告)日：2005-09-07

申请号：EP03796943.3

申请日：2003-12-09

申请人： QUALCOMM INCORPORATED

发明人： KETCHUM, John, W. ,  WALLACE, Mark, S. ,  GAAL, Peter

IPC分类号： H04L25/02 ,  H04B7/06 ,  H04B7/08 ,  H04L1/06

CPC分类号： H04B7/0421 ,  H04B7/0615 ,  H04B7/0842 ,  H04L1/06 ,  H04L25/0204 ,  H04L25/0248 ,  H04L25/03343 ,  H04L2025/03426

摘要： Techniques for deriving eigenvectors based on steered reference and used for spatial processing. A steered reference is a pilot transmission on one eigenmode of a MIMO channel per symbol period using a steering vector for that eigenmode. The steered reference is used to estimate both a matrix Σ of singular values and a matrix U of left eigenvectors of a channel response matrix H . A matrix U with orthogonalized columns may be derived based on the estimates of Σ and U, e.g., using QR factorization, minimum square error computation, or polar decomposition. The estimates of Σ and U (or the estimate of Σ and the matrix U ) may be used for matched filtering of data transmission received via a first link. The estimate U of or the matrix U may also be used for spatial processing of data transmission on a second link (for reciprocal first and second links).

公开(公告)号：EP1557022A2

公开(公告)日：2005-07-27

申请号：EP03779266.0

申请日：2003-10-27

申请人： Qualcomm, Incorporated

发明人： WALTON, Jay, Rodney ,  KETCHUM, John, W. ,  WALLACE, Mark ,  HOWARD, Steven, J.

IPC分类号： H04L27/26 ,  H04L25/02

CPC分类号： H04L5/0007 ,  H04B7/0421 ,  H04B7/043 ,  H04B7/0669 ,  H04B7/0697 ,  H04B7/0854 ,  H04L1/0017 ,  H04L5/0023 ,  H04L5/0028 ,  H04L5/0037 ,  H04L25/0232 ,  H04L25/0248 ,  H04L27/2602 ,  H04W28/20 ,  H04W52/50 ,  H04W72/04

摘要： Techniques to use OFDM symbols of different sizes to achieve greater efficiency for OFDM systems. The system traffic may be arranged into different categories (e.g., control data, user data, and pilot data). For each category, one or more OFDM symbols of the proper sizes may be selected for use based on the expected payload size for the traffic in that category. In a further aspect, the channel response matrix for each of a plurality of subbands is decomposed in a manner to avoid arbitrary phase rotations from subband to subband by constraining the first element in each column of the first unitary matrix to be a non-negative value. In another aspect, steering vectors are interpolated between subbands.

公开(公告)号：EP1516441A1

公开(公告)日：2005-03-23

申请号：EP03761177.9

申请日：2003-06-20

申请人： Qualcomm, Incorporated

发明人： WALTON, Jay, R. ,  KETCHUM, John, W.

IPC分类号： H04B7/04 ,  H04L27/26 ,  H04L1/06 ,  H04B7/06 ,  H04J11/00 ,  H04L1/00

CPC分类号： H04L5/0028 ,  H04B7/04 ,  H04B7/0669 ,  H04B7/0678 ,  H04B7/0697 ,  H04L1/0001 ,  H04L1/0618 ,  H04L5/0007 ,  H04L5/0016 ,  H04L5/0023

摘要： Techniques for transmitting data using a number of diversity transmission modes to improve reliability. At a transmitter, for each of one or more data streams, a particular diversity transmission mode is selected for use from among a number of possible transmission modes. These transmission modes may include a frequency diversity transmission mode, a Walsh diversity transmission mode, a space time transmit diversity (STTD) transmission mode, and a Walsh-STTD transmission mode. Each diversity transmission mode redundantly transmits data over time, frequency, space, or a combination thereof. Each data stream is coded and modulated to provide modulation symbols, which are further processed based on the selected diversity transmission mode to provide transmit symbols.; For OFDM, the transmit symbols for all data streams are further OFDM modulated to provide a stream of transmission symbols for each transmit antenna used for data transmission.

公开(公告)号：EP1440533A2

公开(公告)日：2004-07-28

申请号：EP02789404.7

申请日：2002-10-31

申请人： QUALCOMM Incorporated

发明人： WALTON, Jay, R. ,  KETCHUM, John, W. ,  HOWARD, Steven, J. ,  WALLACE, Mark

IPC分类号： H04L1/00

CPC分类号： H04L1/0015 ,  H04L1/0002 ,  H04L1/0003 ,  H04L1/0009 ,  H04L1/0025 ,  H04L1/0026 ,  Y02D50/10

摘要： Techniques to adaptively control the rate of a data transmission in a wireless (e.g., OFDM) communication system. In an aspect, various types of metrics may be derived and used to select the proper rate for the data transmission. Some types of metrics relate to different characteristics of the communication channel, such as SNR, frequency selectivity, time selectivity, and so on. One type of metric relates to the performance of the data transmission. In another aspect, the various types of metrics may be used in different manners to adaptively control the rate. Some metrics may be used for open-loop control of the rate, other metrics may be used for closed-loop control, and some may be used for both. For example, the channel metrics may be used to determine or select the rate, and the performance metrics may be used to determine whether or not to adjust the rate.

公开(公告)号：EP1438792A2

公开(公告)日：2004-07-21

申请号：EP02801677.2

申请日：2002-10-11

申请人： Qualcomm, Incorporated

发明人： KETCHUM, John, W.

IPC分类号： H04B7/00

CPC分类号： H04B7/0417 ,  H04B7/0443 ,  H04B7/0613 ,  H04B7/0626 ,  H04L5/0023 ,  H04L5/0025 ,  H04L5/0046 ,  H04L5/006 ,  H04W52/34

摘要： In a MIMO communication system (100) with limited power for each antenna, a method, apparatus and a processor (420) provide for determining bin energy level allocation to each OFDM frequency bin at each transmit antenna. An estimate of a solution vector including elements of the allocation bin energy level to each OFDM frequency bin at each antenna is determined. An error function based on the determined solution vector is also determined. An error magnitude is determined based on the determined error function. The error magnitude is compared to an error threshold. The processor (420) accepts the estimate of the solution vector with the elements of the allocation bin energy level when the error magnitude is less than the error threshold.

公开(公告)号：EP1389366A2

公开(公告)日：2004-02-18

申请号：EP02729213.5

申请日：2002-05-17

申请人： QUALCOMM INCORPORATED

发明人： KETCHUM, John, W. ,  HOWARD, Steven, J. ,  WALTON, Jay, Rod ,  WALLACE, Mark, S. ,  LING, Funyun

IPC分类号： H04B7/005

CPC分类号： H04W52/346 ,  H04L1/0009 ,  H04L1/0068 ,  H04L1/06 ,  H04L5/0023 ,  H04L5/0037 ,  H04L5/0046 ,  H04L5/006 ,  H04L5/06 ,  H04L25/03343 ,  H04L2001/0096 ,  H04W52/24 ,  H04W52/42

摘要： Techniques to process data for transmission over a set of transmission channels selected from among all available transmission channels. In an aspect, the data processing includes coding data basd on a common coding and modulation scheme to provide modulation symbols and pre-weighting the modulation symbols for each selected channel based on the channel's characteristics. The pre-weighting may be achieved by 'inverting' the selected channels so that the received SNRs are approximately similar for all selected channels. With selective channel inversion, only channels having SNRs at or above a particular threshold are selected, 'bad' channels are not used, and the total available transmit power is distributed across only 'good' channels. Inproved performance is achieved due to the combined benefits of using only the Ns best channels and matching the received SNR of each selected channel to the SNR required by the selected coding and modulation scheme.