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公开(公告)号：CA2671681C
公开(公告)日：2015-01-06
申请号：CA2671681
申请日：2008-01-02
Applicant: QUALCOMM INC
Inventor： BJERKE BJORN , HOWARD STEVEN J
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.
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192.发明专利
公开(公告)号：PL1933513T3
公开(公告)日：2014-10-31
申请号：PL08153985
申请日：2004-12-13
Applicant: QUALCOMM INC
Inventor： WALTON JAY , KETCHUM JOHN W , WALLACE MARK S , HOWARD STEVEN J
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公开(公告)号：CA2810036C
公开(公告)日：2014-09-02
申请号：CA2810036
申请日：2003-10-24
Applicant: QUALCOMM INC
Inventor： WALTON J RODNEY , KETCHUM JOHN W , WALLACE MARK S , HOWARD STEVEN J
IPC: H04W74/08 , H04B7/005 , H04B7/04 , H04B7/06 , H04B7/08 , H04J99/00 , H04L1/00 , H04L1/06 , H04L1/08 , H04L1/16 , H04L12/28 , H04L12/56 , H04L25/02 , H04L25/03 , H04L27/26 , H04W28/20 , H04W52/50
Abstract: Techniques for facilitating random access in wireless multiple-access communication systems. A random access channel (RACH) is defined to comprise a "fast" RACH (F-RACH) and a "slow" RACH (S-RACH). The F-RACH and S-RACH can efficiently support user terminals in different operating states and employ different designs. The F-RACH can be used to quickly access the system, and the S-RACH is more robust and can support user terminals in various operating states and conditions. The F- RACH may be used by user terminals that have registered with the system and can compensate for their round trip delays (RTDs) by properly advancing their transmit timing. The S- RACH may be used by user terminals that may or may not have registered with the system, and may or may not be able to compensate for their RTDs. The user terminals may use the F- RACH or S-RACH, or both, to gain access to the system.
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194.发明专利
公开(公告)号：DK1933513T3
公开(公告)日：2014-08-11
申请号：DK08153985
申请日：2004-12-13
Applicant: QUALCOMM INC
Inventor： WALTON JAY , KETCHUM JOHN W , WALLACE MARK S , HOWARD STEVEN J
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公开(公告)号：CA2776970C
公开(公告)日：2014-08-05
申请号：CA2776970
申请日：2007-05-22
Applicant: QUALCOMM INC
Inventor： WALLACE MARK S , KETCHUM JOHN W , WALTON JAY RODNEY , HOWARD STEVEN J
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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Patent Agency Ranking196.发明专利
公开(公告)号：CA2747374C
公开(公告)日：2014-03-11
申请号：CA2747374
申请日：2005-02-18
Applicant: QUALCOMM INC
Inventor： WALTON JAY RODNEY , KETCHUM JOHN W , WALLACE MARK S , HOWARD STEVEN J , NANDA SANJIV
Abstract: A multi-antenna transmitting entity transmits data to a single- or multi--antenna receiving entity using (1) a steered mode to direct the data transmission toward the receiving entity or (2) a pseudo-random transmit steering (PRTS) mode to randomize the effective channels observed by the data transmission across the subbands. The PRTS mode may be used to achieve transmit diversity or spatial spreading. For transmit diversity, the transmitting entity uses different pseudo- random steering vectors across the subbands but the same steering vector across an entire packet for each subband. The receiving entity does not need to have knowledge of the pseudo-random steering vectors or perform any special processing. For spatial spreading, the transmitting entity uses different pseudo-random steering vectors across the subbands and different steering vectors across the packet for each subband. Only the transmitting and receiving entities know the steering vectors used for data transmission.
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公开(公告)号：ES2436766T3
公开(公告)日：2014-01-07
申请号：ES07011912
申请日：2002-05-15
Applicant: QUALCOMM INC
Inventor： WALTON JAY R , WALLACE MARK , HOWARD STEVEN J
Abstract: Un procedimiento de planificación de la transmisión de datos en un sistema (100) de comunicación inalámbrica, estando el procedimiento implementado por una estación base (104), y comprendiendo el procedimiento: formar múltiples conjuntos de terminales (106) para recibir la transmisión de datos desde la estación base (104) en un próximo intervalo de transmisión, incluyendo cada conjunto uno o más terminales (106), y correspondiendo a una hipótesis distinta, a evaluar en base a uno o más criterios, en donde los múltiplesconjuntos de terminales (106) incluyen un primer conjunto de uno o más terminales (106) correspondientes auna primera hipótesis a evaluar, y un segundo conjunto de uno o más terminales (106) correspondientes a unasegunda hipótesis a evaluar, y en donde dichos uno o más terminales (106) en el primer conjunto son distintos adichos uno o más terminales (106) en el segundo conjunto; asignar una pluralidad de antenas (524) de transmisión a dichos uno o más terminales (106) en cada conjunto;evaluar el rendimiento de cada hipótesis en base a la información de estado de canal, CSI, asociada a cadaterminal (106), siendo la CSI indicativa de las características de canal entre el respectivo terminal (106) y lascorrespondientes antenas transmisoras (524); seleccionar una de las múltiples hipótesis evaluadas, en base al rendimiento; y planificar la transmisión de datos a dichos uno o más terminales (106) en la hipótesis seleccionada.
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公开(公告)号：CA2650783C
公开(公告)日：2013-09-24
申请号：CA2650783
申请日：2007-05-22
Applicant: QUALCOMM INC
Inventor： WALLACE MARK S , KETCHUM JOHN W , WALTON JAY RODNEY , HOWARD STEVEN J
IPC: H04W24/00
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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公开(公告)号：CA2787842C
公开(公告)日：2013-08-20
申请号：CA2787842
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
Abstract: 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.
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公开(公告)号：CA2756728C
公开(公告)日：2013-05-21
申请号：CA2756728
申请日：2003-10-27
Applicant: QUALCOMM INC
Inventor： WALTON JAY RODNEY , KETCHUM JOHN W , WALLACE MARK , HOWARD STEVEN J
IPC: H04W24/02 , H04B7/005 , H04B7/04 , H04B7/06 , H04B7/08 , H04J11/00 , H04J99/00 , H04L1/00 , H04L1/06 , H04L1/16 , H04L12/28 , H04L12/56 , H04L25/02 , H04L25/03 , H04L27/26 , H04W16/10 , H04W28/20 , H04W52/50
Abstract: 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. For example, control data may be transmitted using OFDM symbols of a first size, user data may be transmitted using OFDM symbols of the first size and a second size, and pilot data may be transmitted using OFDM symbols of a third size or the first size. In one exemplary design, a small OFDM symbol is utilized for pilot and for transport channels used to send control data, and a large OFDM symbol and the small OFDM symbol are utilized for transport channels used to send user data.
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