公开(公告)号：AU2002329933A1

公开(公告)日：2003-03-18

申请号：AU2002329933

申请日：2002-08-30

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD

IPC: H04L27/01 ,  H04B1/10 ,  H04B7/08 ,  H04B7/26 ,  H04L1/00 ,  H04L25/02 ,  H04L25/03

Abstract: Method and apparatus for pre-coding in a communication system are disclosed. In a communication system, an origination station transmits a non pre-coded pilot signal and a pre-coded data signal. A destination station estimates a metric characterizing a communication channel using the non pre-coded pilot signal. The metric is then used to pre-code the data signal to be transmitted. The destination station may also use the estimated metric for demodulation of the pre-coded data. However, since the pilot signal is not pre-coded, the metric for the desired multi-path of the pilot channel differs from that of the pre-coded data channel, which may reduce the demodulation performance. To improve the channel estimation for data demodulation, the origination station may additionally transmit a dedicated pilot signal that is pre-coded in the same manner as the data signal destined to a specific user.

公开(公告)号：NO20024634D0

公开(公告)日：2002-09-27

申请号：NO20024634

申请日：2002-09-27

Applicant: QUALCOMM INC

Inventor： WALLACE MARK S ,  WALTON JAY R ,  JALALI AHMAD

IPC: H04B1/707 ,  H04J11/00 ,  H04B7/06 ,  H04B7/08 ,  H04B7/12 ,  H04B7/26 ,  H04B17/00 ,  H04J99/00 ,  H04L25/02 ,  H04L27/26 ,  H04W52/08 ,  H04W52/42 ,  H04B

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.

公开(公告)号：AU8862001A

公开(公告)日：2002-03-13

申请号：AU8862001

申请日：2001-08-31

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD ,  SMEE JOHN ,  AGASHE PARAG

IPC: H04B7/005 ,  H04B7/06 ,  H04B7/26 ,  H04B7/00

Abstract: In a CDMA data communication system capable of variable rate data transmission, a time-division power assignment cyclically reduces the carrier power level to at least one sector to reduce interference in neighboring sectors. The base station determines a time-division power assignment for each sector and generates signals according to the power assignment. The mobile unit generates filter coefficients corresponding to each power level. The mobile unit estimates Carrier Signal-to-Interference (C/I) to determine a data rate for each power level. Previous iterations of the equalizer are stored and used to refine future estimates.

公开(公告)号：BRPI0013670B1

公开(公告)日：2015-11-10

申请号：BR0013670

申请日：2000-08-31

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD

IPC: H04B7/06 ,  H04B7/26

Abstract: "método e aparelho para formação de feixe em um sistema de comunicação sem fio". em um sistema de comunicação de dados cdma capaz de transmissão em taxa variável, a utilização de técnicas de formação de feixe diminui a interferência média causada por transmissões de uma estação base (104) para estações assinantes (112) em células vizinhas (124). estações base (102, 104) utilizam múltiplas antenas transmissoras (106, 108), cada uma transmitindo sinais em fases controladas, para formar feixes de sinais de transmissão (110, 118, 122) correspondendo a estações assinantes individuais (112, 116, 114). sinais de dados e de referência são transmitidos ao longo de feixes (110, 118, 122) que se modificam de acordo com slots e sub-slots de tempo fixados a fim de maximizar as relações portadora/interferência (c/i) medidas em estações assinantes (112, 116, 114).

公开(公告)号：PT1816759E

公开(公告)日：2012-07-02

申请号：PT07010284

申请日：2000-08-31

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD

IPC: H04B7/06 ,  H04B7/26

公开(公告)号：ES2383537T3

公开(公告)日：2012-06-22

申请号：ES07010284

申请日：2000-08-31

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD

IPC: H04B7/06 ,  H04B7/26

Abstract: Un procedimiento de transmisión de datos desde una primera estación base (104) de una pluralidad de estaciones base (102, 104) a una estación (120) de abonado, comprendiendo el procedimiento: transmitir, dentro de una primera ranura (204A) de tiempo, y a lo largo de un primer haz de señales, una ráfaga de señales de referencia; transmitir, dentro de dicha primera ranura (204A) de tiempo, y a lo largo de un segundo haz de señales, una primera porción de datos de ranura de tiempo; recibir información de medición de canal procedente de la estación (120) de abonado, correspondiendo la información de medición a mediciones de dicha ráfaga de señales de referencia realizadas en la estación (120) de abonado; y transmitir, dentro de una segunda ranura (204B) de tiempo, a lo largo (204B) de dicha primera ráfaga de señales, una segunda porción de datos de ranura de tiempo, siguiendo la segunda ranura (204B) de tiempo a dicha primera ranura (204A) de tiempo tras un número predeterminado de ranuras de tiempo intermedias, y estando la transmisión de la segunda porción de datos de ranura de tiempo a una velocidad de transferencia de datos que se basa en la información de medición de canal.

公开(公告)号：AT556495T

公开(公告)日：2012-05-15

申请号：AT07010284

申请日：2000-08-31

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD

IPC: H04B7/06 ,  H04B7/26

Abstract: In a CDMA data communication system capable of variable rate transmission, utilization of beamforming techniques decreases the average interference caused by transmissions of a base station (104) to subscriber stations (112) in neighboring cells (124). Base stations (102, 104) utilize multiple transmit antennas (106, 108), each transmitting signals at controlled phases, to form transmit signal beams (110, 118, 122) corresponding to individual subscriber stations (112, 116, 114). Data and reference signals are transmitted along beams (110, 118, 122) that change according to fixed time slots and subslots in order to maximize carrier-to-interference ratios (C/I) measured at subscriber stations (112, 116, 114).

公开(公告)号：CA2406216C

公开(公告)日：2012-02-07

申请号：CA2406216

申请日：2001-04-13

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD ,  ESTEVES EDUARDO A S ,  SINDHUSHAYANA NAGABHUSHANA T ,  BLACK PETER J ,  ATTAR RASHID A

IPC: H04L1/18 ,  H04L1/16 ,  H04Q7/38

Abstract: A transmitting terminal, transmits signals in a form of packets to a receiving terminal, if the packet was intended for the receiving terminal, if so, the receiving terminal demodulates the packet. The receiving terminal then computes a quality metric of the packet, and compares the computed quality metric with a quality metric contained in the packet. If the quality metrics match, the packet is forwarded for further processing. If the quality metrics fail to match, the receiving terminal sends a request for retransmission of the packet. The transmitting terminal determines which packet needs to be retransmitted based on the request for retransmission. If delivery of the packet in accordance with the aforementioned description fails, retransmission in accordance with conventional sequence-number-based schemes, e.g., radio link protocol, is attempted.

公开(公告)号：AT534198T

公开(公告)日：2011-12-15

申请号：AT05015739

申请日：2001-03-20

Applicant: QUALCOMM INC

Inventor： WALLACE MARK ,  WALTON JAY R ,  JALALI AHMAD

IPC: H04B7/00 ,  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.

公开(公告)号：AU2008261159C1

公开(公告)日：2010-09-23

申请号：AU2008261159

申请日：2008-12-22

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD

IPC: H04L12/24 ,  H04J11/00 ,  H04J13/00 ,  H04J13/18 ,  H04L12/56 ,  H04W28/14 ,  H04W28/22 ,  H04W28/26 ,  H04W72/02 ,  H04W74/08 ,  H04W84/06

Abstract: In a code division multiple access (CDMA) communications system including one or more terminals (such as customer premise equipments, CPEs) that communicate with a node (such as an Internet gateway) via at least a random access channel and a reservation-oriented channel, various schemes of managing communications traffic among the channels are provided. Decisions as to the channel on which a given terminal may transmit may be based on: traffic statistics (such as packet size or average data rate over a time period), traffic content (such as packet type), the terminal's output buffer loading (queue state, or “Q-state”), a history of the terminal's output buffer loading (one or more Q-states), and so forth. In one application, decisions in managing traffic in a live user's web browsing sessions may involve intelligent ascertainment of whether a given terminal is busy based on traffic analysis or output buffer loading.