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公开(公告)号：CA2174342A1
公开(公告)日：1995-05-11
申请号：CA2174342
申请日：1994-10-27
Applicant: QUALCOMM INC
Inventor： SIH GILBERT C , ANTONIO FRANKLIN P
Abstract: An apparatus that automatically adjusts the adaptation block size for a least-mean square (LMS) adaptive filter depending on the input signal-to-noise ratio (SNR) is disclosed. The apparatus monitors the instantaneous SNR and continually adjusts the block size to provide high noise immunity, thereby increasing the convergence speed of the filter and decreasing the asymptotic mean-square error. An exemplary embodiment of the present invention is presented in the context of acoustic echo cancellation, though it is noted that the adaptive filter of the present invention is useful in any environment in which the noise characteristics are subject to change.
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公开(公告)号：CZ127194A3
公开(公告)日：1994-12-15
申请号：CZ127194
申请日：1993-09-24
Applicant: QUALCOMM INC
Inventor： SIH GILBERT C
IPC: H04M1/60 , G10L19/012 , H04B3/23 , H04M9/08
Abstract: An echo canceller and method for cancelling in a return channel signal an echoed receive channel signal where the echoed receive channel signal is combined by an echo channel with an input return channel signal. The echo canceller has a first filter which generates first filter coefficients, generates a first echo estimate signal with the first filter coefficients, and updates the first filter coefficients in response to a first filter control signal. A first summer subtracts the first echo estimate signal from a combined return channel and echo receive channel signal to generate a first echo residual signal. A second filter generates second filter coefficients, generates a second echo estimate signal with the second filter coefficients, and updates the second filter coefficients in response to a second filter control signal. A second summer subtracts the second echo estimate signal from the combined signal to generate a second echo residual signal, and provides upon the return channel the second echo residual signal. A control unit determines from the receive channel signal, the combined signal, and the first and second echo residual signals, one of a plurality of control states wherein a first control state is indicative of a receive channel signal above a first predetermined energy level, wherein when the control unit is in the first control state it generates the first control signal and generates the second control signal when at least one of a first energy ratio of the first echo residual signal and the combined signal and a second energy ratio of the second echo residual signal and the combined signal exceed a predetermined level.
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公开(公告)号：MX9305889A
公开(公告)日：1994-05-31
申请号：MX9305889
申请日：1993-09-24
Applicant: QUALCOMM INC
Inventor： SIH GILBERT C
IPC: G10L19/012 , H04M1/60 , H04B3/23 , H04M9/08 , H04M1/00
Abstract: An echo canceller and method for cancelling in a return channel signal an echoed receive channel signal where the echoed receive channel signal is combined by an echo channel with an input return channel signal. The echo canceller has a first filter which generates first filter coefficients, generates a first echo estimate signal with the first filter coefficients, and updates the first filter coefficients in response to a first filter control signal. A first summer subtracts the first echo estimate signal from a combined return channel and echo receive channel signal to generate a first echo residual signal. A second filter generates second filter coefficients, generates a second echo estimate signal with the second filter coefficients, and updates the second filter coefficients in response to a second filter control signal. A second summer subtracts the second echo estimate signal from the combined signal to generate a second echo residual signal, and provides upon the return channel the second echo residual signal. A control unit determines from the receive channel signal, the combined signal, and the first and second echo residual signals, one of a plurality of control states wherein a first control state is indicative of a receive channel signal above a first predetermined energy level, wherein when the control unit is in the first control state it generates the first control signal and generates the second control signal when at least one of a first energy ratio of the first echo residual signal and the combined signal and a second energy ratio of the second echo residual signal and the combined signal exceed a predetermined level.
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公开(公告)号：ES2398091T3
公开(公告)日：2013-03-13
申请号：ES01110152
申请日：1993-09-24
Applicant: QUALCOMM INC
Inventor： SIH GILBERT C
IPC: G10L19/012 , G10L19/00 , H04B3/23 , H04M1/60 , H04M9/08
Abstract: Un procedimiento para realizar compensación de eco en un compensador (140) de eco, teniendo dichocompensador de eco una pluralidad de estados predeterminados en base a la presencia de señales de habla delextremo cercano y extremo lejano, que comprende los pasos de: recibir dicha señal de habla del extremo lejano a partir de un canal del extremo lejano en comunicación condicho compensador (140) de eco; escalar dicha señal de habla del extremo lejano para proporcionar una señal de habla del extremo lejanoajustada: detectando un estado de habla a partir de dicha pluralidad de estados en base a dicha señal de habla delextremo lejano y dicha señal de habla del extremo cercano, y ajustando dicha señal de habla del extremo lejano en base a dicho estado de habla; recibir una señal de eco desde un canal de eco; y compensar el eco de dicha señal de eco al menos parcialmente en base a dicha señal de habla del extremo lejanoajustada.
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公开(公告)号：AT510351T
公开(公告)日：2011-06-15
申请号：AT02709570
申请日：2002-02-15
Applicant: QUALCOMM INC
Inventor： LI TAO , HOLENSTEIN CHRISTIAN , KANG INJUP , WALKER BRETT , PETERZELL PAUL , CHALLA RAGHU , SEVERSON MATTHEW , RAGHUPATHY ARUN , SIH GILBERT C
Abstract: An apparatus and method in a wireless communication system, the apparatus comprising: first means for amplifying a received signal; means for cancelling a DC offset in the amplified signal; second means for digitally amplifying the DC offset cancelled signal; and means for measuring the digitally amplified signal and to control the gains of the first and second amplifying means.
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Patent Agency Ranking56.发明专利
公开(公告)号：DE69943231D1
公开(公告)日：2011-04-07
申请号：DE69943231
申请日：1999-09-03
Applicant: QUALCOMM INC
Inventor： KANG INYUP , ZOU QUIZHEN , SIH GILBERT C
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公开(公告)号：AT499617T
公开(公告)日：2011-03-15
申请号：AT08013899
申请日：1999-09-03
Applicant: QUALCOMM INC
Inventor： KANG INYUP , ZOU QUIZHEN , SIH GILBERT C
IPC: G01S5/00 , G01S1/00 , G01S1/04 , G01S19/23 , G01S19/25 , G01S19/30 , G01S19/48 , H04M1/725 , H04Q7/34
Abstract: A mobile device (10) comprises a receiver and a coherent integrator (104), wherein the receiver is configured to receive a first signal from a satellite, the first signal including a navigation message. The coherent integrator is configured to coherently integrate first signal samples for a particular coherent integration interval. When the coherent integration interval straddles a data boundary of the navigation message, the coherent integration is divided into a section before the data boundary of the navigation message and a section after the data boundary of the navigation message
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公开(公告)号：CA2347239C
公开(公告)日：2010-04-27
申请号：CA2347239
申请日：1999-10-12
Applicant: QUALCOMM INC
Inventor： BUTLER BRIAN K , ZHANG HAITAO , TIEDEMANN EDWARD G JR , ZOU QIUZHEN , SIH GILBERT C , AGRAWAL AVNEESH
IPC: H04W24/02 , H04B1/7075 , H04B1/7077 , H04B1/7115 , H04W52/02
Abstract: A novel and improved method for performing paging is described. In one embodiment of the invention a searcher (206) is used to detect spread spectrum signals. Samples received RF signals are stored in a sample buffer. During standby mode, the samples are gathered during paging slots assigned to the mobile. A set of searches are performed on the samples, and if pilot signals are detected additional demodulation is performed to detect paging messages. The resulting set of demodulation data may be combined to increase detection. After a page message has been detected, additional demodulation resources may be activated to process more complete page messages, or other information channels. In one embodiment of the invention, the searcher (206) includes a demodulator to perform quick page detection without the use of finger elements to reduce idle mode power consumption.
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公开(公告)号：FI120568B
公开(公告)日：2009-11-30
申请号：FI19991937
申请日：1999-09-10
Applicant: QUALCOMM INC
Inventor： SIH GILBERT C , GUPTA SAMIR KUMAR
Abstract: A method and apparatus for canceling both earseal and hybrid echo in a Wireless Local Loop telephone system is disclosed. The present invention operates within a subscriber station having a plurality of telephone inputs, one of which is a dedicated handset and at least one other input being a standard analog telephone. During a conference call between a far end speaker and two near end speakers, the far end speaker may hear an echo of his own voice due to an earseal echo generated by the dedicated handset and a hybrid echo generated by a 4-to-2 wire hybrid interface within the subscriber station. In accordance with the present invention, two distinct echo cancellers are used in the subscriber station to reduce the two types of echo. A first echo canceller is optimized to remove the earseal echo generated at the dedicated handset while a second echo canceller is optimized to remove the hybrid echo generated at the 4-to-2 wire hybrid. The two echo cancellers operate independently such that neither echo canceller need adapt its filter coefficients when a change in the echo channel characteristics occur, such as when a speaker hangs up or another speaker joins the conversation.
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公开(公告)号：DE60035367T2
公开(公告)日：2008-02-28
申请号：DE60035367
申请日：2000-12-20
Applicant: QUALCOMM INC
Inventor： SIH GILBERT C , FEVRIER IAN , KANG INYUP , PATRICK CHRISTOPHER
IPC: G06F17/15 , H04B1/7093 , H04B7/26
Abstract: A novel and improved method and apparatus for searching is described. This searcher combines the ability to search multiple offsets of single pilots, such as those found in the IS-95 system, with the ability to search multiple pilots, such as those found in a GPS location determination system. Both types of searching can be done in a single architecture combining the parallel computation features of a matched filter with the flexibility of allowing a variable number of coherent accumulations and a variable number of non-coherent accumulations to be performed at high speed for a wide range of search hypotheses in a resource efficient manner. This invention allows for parallel use of the matched filter structure in a time-sliced manner to search multiple windows. In addition, the searcher allows for optional independent Walsh decovering for each search window. The time-sharing approach allows for optional frequency searching of any offset.
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