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公开(公告)号：CA2690245A1
公开(公告)日：2001-10-11
申请号：CA2690245
申请日：2001-03-20
Applicant: QUALCOMM INC
Inventor： WALLACE MARK , WALTON JAY R , JALALI AHMAD
IPC: H04J11/00 , H04W24/10 , H04B1/707 , H04B7/02 , H04B7/06 , H04B7/08 , H04B7/12 , H04B7/26 , H04B17/00 , H04J99/00 , H04L25/02 , H04L27/26 , H04W52/08 , H04W52/42
Abstract: Channel state information (CSI) can be used by a communications system to precondition transmissions between transmitter units and receiver units. In one aspect of the invention, disjoint sub-channel sets are assigned to transmit antennas located at a transmitter unit. Pilot symbols are generated and transmitted on a subset of the disjoint sub-channels. Upon receipt of the transmitted pilot symbols, the receiver units determine the CSI for the disjoint sub-channels that carried pilot symbols. These CSI values are reported to the transmitter unit, which will use these CSI values to generate CSI estimates for the disjoint sub-channels that did not carry pilot symbols. The amount of information necessary to report CSI on the reverse link can be further minimized through compression techniques and resource allocation techniques.
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公开(公告)号：CA2402152A1
公开(公告)日：2001-10-11
申请号：CA2402152
申请日：2001-03-20
Applicant: QUALCOMM INC
Inventor： JALALI AHMAD , WALTON JAY R , WALLACE MARK
IPC: H04J11/00 , H04B1/707 , H04B7/06 , H04B7/08 , H04B7/12 , H04B7/26 , H04B17/00 , H04J99/00 , H04L25/02 , H04L27/26 , H04W52/08 , H04W52/42
Abstract: The invention relates to a method for transmitting pilot signals used for measuring and reporting channel state information, CSI, in a multiple input/multiple output, MIMO, system, comprising: generating a pilot sequence by using a maximal-length shift register sequence, m-sequence; assigning a different shift to multiple transmit antennas, wherein the value of the shift is dependent on at least one characteristic of the communication channel; generating a pilot signal at each transmit antenna by shifting the pilot sequence by the value specified by the shift; and transmitting the pilot signal via the transmit antenna.
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公开(公告)号：BRPI0209521B1
公开(公告)日：2016-03-29
申请号：BR0209521
申请日：2002-05-07
Applicant: QUALCOMM INC
Inventor： WALTON JAY R , KETCHUM JOHN W , WALLACE MARK , HOWARD STEVEN J
Abstract: "método e equipamento para processar dados em um sistema de comunicação de múltiplas entradas e múltiplas saídas (mimo)utilizando informações de estado de canal". técnicas para processar "sucessivamente" sinais recebidos em uma unidade receptora em um sistema mimo para recuperar dados transmitidos e para processar dados "de forma adaptável" em uma unidade transmissora com base em informações de estado de canal disponíveis para o canal mimo. é utilizada uma técnica de processamento de receptor de cancelamento sucessivo para processar os sinais recebidos e efetuar um número de interações para prover fluxos de dados decodificados. para cada interação, sinais de entradas (por exemplo recebidos) são processados para prover um ou mais fluxos de símbolos. um ou mais dos fluxos de símbolos são selecionados e processados para prover um fluxo de dados decodificado. a interferência devido ao fluxo de dados decodificado é aproximadamente removida (isto é, cancelada) dos sinais de entrada providos para a próxima interação. as características de canal são estimadas e reportadas de volta ao sistema transmissor e utilizadas para ajustar (isto é, adaptar) o processamento (por exemplo, codificação, modulação e assim por diante) dos dados antes da transmissão
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公开(公告)号：CA2690245C
公开(公告)日：2015-09-01
申请号：CA2690245
申请日：2001-03-20
Applicant: QUALCOMM INC
Inventor： WALLACE MARK , WALTON JAY R , JALALI AHMAD
IPC: H04J11/00 , H04W24/10 , H04B1/707 , H04B7/02 , H04B7/06 , H04B7/08 , H04B7/12 , H04B7/26 , H04B17/00 , H04J99/00 , H04L25/02 , H04L27/26 , H04W52/08 , H04W52/42
Abstract: Channel state information (CSI) can be used by a communications system to precondition transmissions between transmitter units and receiver units. In one aspect of the invention, disjoint sub-channel sets are assigned to transmit antennas located at a transmitter unit. Pilot symbols are generated and transmitted on a subset of the disjoint sub- channels. Upon receipt of the transmitted pilot symbols, the receiver units determine the CSI for the disjoint sub-channels that carried pilot symbols. These CSI values are reported to the transmitter unit, which will use these CSI values to generate CSI estimates for the disjoint sub-channels that did not carry pilot symbols. The amount of information necessary to report CSI on the reverse link can be further minimized through compression techniques and resource allocation techniques.
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公开(公告)号：CA2698363C
公开(公告)日：2014-12-02
申请号：CA2698363
申请日：2001-03-20
Applicant: QUALCOMM INC
Inventor： WALTON JAY R , WALLACE MARK , HOLTZMAN JACK , ANTONIO FRANKLIN P
IPC: H04J1/05 , H04W72/10 , H04B7/005 , H04B7/26 , H04J3/00 , H04J11/00 , H04W52/18 , H04W52/24 , H04W52/26 , H04W52/34
Abstract: In some aspects, each cell in the communications system can be designed to operate in accordance with a set of back-off factors that identify the reductions in peak transmit power levels for the channels associated with the back-off factors. The back-off factors are defined to provide the required power to a large percentage of the users while reducing the amount of interference. In some other aspects, the cells operate using an adaptive reuse scheme that allows the cells to efficiently allocate and reallocate the system resources to reflect changes in the system. A reuse scheme is initially defined and resources are allocated to the cells. During operation, changes in the operating conditions of the system are detected and the reuse scheme is redefined as necessary based on the detected changes. For example, the loading conditions of the cells can be detected, and the resources can be reallocated and/or the reuse scheme can be redefined. In yet other aspects, techniques are provided to efficiency schedule data transmissions and to assign channels to users. Data transmissions can be scheduled based on user priorities, some fairness criteria, system requirements, and other factors. Users are assigned to available channels based on a number of channel assignment schemes. Channel metrics are also provided, which can be used to prioritize users and for channel assignments.
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Patent Agency Ranking
公开(公告)号：CA2490520C
公开(公告)日：2013-11-19
申请号：CA2490520
申请日：2003-06-20
Applicant: QUALCOMM INC
Inventor： WALTON JAY R , KETCHUM JOHN W
IPC: H04B7/04 , H04J11/00 , H04B1/00 , H04B7/02 , H04B7/06 , H04B7/12 , H04B7/26 , H04J99/00 , H04L1/00 , H04L1/06 , H04L27/26
Abstract: 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.
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117.发明专利
公开(公告)号：CA2446877C
公开(公告)日：2013-01-29
申请号：CA2446877
申请日：2002-05-15
Applicant: QUALCOMM INC
Inventor： WALTON JAY R , WALLACE MARK , HOWARD STEVEN J
IPC: H04W72/12 , H04B7/04 , H04B7/06 , H04J99/00 , H04L1/00 , H04L1/06 , H04W4/06 , H04W16/00 , H04W16/10 , H04W16/28 , H04W84/14
Abstract: Techniques to schedule downlink data transmission to a number of terminals in a wireless communication system. In one method, one or more sets of terminals are formed for possible data transmission, with each set including a unique combination of one or more terminals and corresponding to a hypothesis to be evaluated. One or more sub-hypotheses may further be formed for each hypothesis, with each sub-hypothesis corresponding to specific assignments of a number of transmit antennas to the one or more terminals in the hypothesis. The performance of each sub-hypothesis is then evaluated, and one of the evaluated sub-hypotheses is selected based on their performance. The terminal(s) in the selected sub-hypothesis are then scheduled for data transmission, and data is thereafter coded, modulated, and transmitted to each scheduled terminal from one or more transmit antenna assigned to the terminal.
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公开(公告)号：DK1628419T3
公开(公告)日：2012-03-05
申请号：DK05015739
申请日：2001-03-20
Applicant: QUALCOMM INC
Inventor： WALLACE MARK , WALTON JAY R , JALALI AHMAD
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公开(公告)号：ES2374732T3
公开(公告)日：2012-02-21
申请号：ES05015739
申请日：2001-03-20
Applicant: QUALCOMM INC
Inventor： WALLACE MARK , WALTON JAY R , JALALI AHMAD
IPC: H04B1/707 , H04B7/00 , H04B7/06 , H04J11/00 , H04B7/08 , H04B7/12 , H04B7/26 , H04B17/00 , H04J99/00 , H04L25/02 , H04L27/26 , H04W52/08 , H04W52/42
Abstract: Un procedimiento de transmisión de símbolos piloto en un sistema (100) de comunicación de múltiples antenas, que comprende: asignar cada una entre una pluralidad de antenas, NT, con una pluralidad de símbolos piloto y un subconjunto distinto entre una pluralidad de subconjuntos de subcanales, en donde cada uno entre la pluralidad de subconjuntos de subcanales incluye un subconjunto distinto de una pluralidad de subcanales, y en donde cada antena transmite por cada NT-ésimo subcanal a través del canal, de modo tal que todos los subcanales sean disjuntos entre las antenas transmisoras; modular cada uno entre la pluralidad asignada de símbolos piloto sobre la respectiva pluralidad asignada de subconjuntos de subcanales; y transmitir cada uno entre la pluralidad asignada de símbolos piloto desde la pluralidad de antenas simultáneamente, usando la respectiva pluralidad de subconjuntos de subcanales, en donde la transmisión desde cada antena ocurre por el subconjunto de subcanales asignado a la antena.
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120.发明专利
公开(公告)号：CA2404055C
公开(公告)日：2012-01-03
申请号：CA2404055
申请日：2001-03-20
Applicant: QUALCOMM INC
Inventor： WALTON JAY R , WALLACE MARK , HOLTZMAN JACK , ANTONIO FRANKLIN P
Abstract: In some aspects, each cell in the communications system can be designed to operate in accordance with a set of back-off factors that identify the reductions in peak transmit power levels for the channels associated with the back-off factors. The back-off factors are defined to provide the required power to a large percentage of the users while reducing the amount of interference. In some other aspects, the cells operate using an adaptive reuse scheme that allows the cells to efficiently allocate and reallocate the system resources to reflect changes in the system. A reuse scheme is initially defined and resources are allocated to the cells. During operation, changes in the operating conditions of the system are detected and the reuse scheme is redefined as necessary based on the detected changes. For example, the loading conditions of the cells can be detected, and the resources can be reallocated and/or the reuse scheme can be redefined. In yet other aspects, techniques are provided to efficiency schedule data transmissions and to assign channels to users. Data transmissions can be scheduled based on user priorities, some fairness criteria, system requirements, and other factors. Users are assigned to available channels based on a number of channel assignment schemes. Channel metrics are also provided, which can be used to prioritize users and for channel assignments.
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