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    A method and apparatus for compressing signals in a fixed point format without introducing a bias
    91.
    发明专利
    A method and apparatus for compressing signals in a fixed point format without introducing a bias 未知

    公开(公告)号：AU767325B2

    公开(公告)日：2003-11-06

    申请号：AU5486699

    申请日：1999-08-13

    Applicant: QUALCOMM INC

    Inventor： RIDDLE CHRISTOPHER C ,  LEVIN JEFFREY A

    IPC: H03M7/24 ,  G06F7/48 ,  H03M7/34 ,  H03M7/00 ,  H03M3/02

    Abstract: A method and apparatus for compressing fixed point signals without introducing a bias. Signals are compressed according to a dithered rounding approach wherein signal values are rounded up and rounded down with approximately equal probability, canceling the bias that would otherwise result from the rounding operation. Numerical properties of the input signal are exploited in order to determine whether the signal value should be rounded up or down. Signal compression may, therefore, be introduced at multiple points within a system without accumulating a signal bias and degrading downstream performance. Further, one bit signal compression may be achieved in a particularly efficient fashion with a minimal amount of hardware.

    92.
    发明专利
    未知

    公开(公告)号：DK0732013T3

    公开(公告)日：2003-09-15

    申请号：DK95937306

    申请日：1995-09-27

    Applicant: QUALCOMM INC

    Inventor： LEVIN JEFFREY A ,  EASTON KENNETH D

    IPC: H04L1/02 ,  H04B1/707 ,  H04B7/26 ,  H04J11/00 ,  H04J13/00 ,  H04L27/30 ,  H04Q7/20

    Abstract: An integrated search processor used in a modem for a spread spectrum communications system buffers receive samples and utilizes a time sliced transform processor operating on successive offsets from the buffer. The search processor autonomously steps through a search as configured by a microprocessor specified search parameter set, which can include the group of antennas to search over, the starting offset and width of the search window to search over, and the number of Walsh symbols to accumulate results at each offset. The search processor calculates the correlation energy at each offset, and presents a summary report of the best paths found in the search to use for demodulation element reassignment. This reduces the searching process related workload of the microprocessor and also reduces the modem costs by allowing a complete channel element modem circuit to be produced in a single IC.

    93.
    发明专利
    未知

    公开(公告)号：BR0011412A

    公开(公告)日：2003-07-15

    申请号：BR0011412

    申请日：2000-06-09

    Applicant: QUALCOMM INC

    Inventor： RIDDLE CHRISTOPHER C ,  LEVIN JEFFREY A

    IPC: H04L25/02

    Abstract: A Wireless Code Division Multiple Access method and apparatus for determining the transmitted rate of a voice/data signal from a mobile station to a Base Station. Variable rate vocoders transmit voice at one of several predetermined frame rates. The receiver determines the transmitted rate based on one of several frame parameters. One of the parameters is received frame energy. The received frame energy is measured over the length of the relevant portion of the frame. Energy is measured over the half of the frame that can only contain energy if a full rate frame is sent. If the energy measured exceeds a threshold, then full rate is indicated. Else, energy is measured over the fourth of a frame that can only contain energy if a half rate frame is sent. If the energy exceeds a threshold, then half rate is indicated. The procedure is repeated for quarter and eighth rates.

    METODO Y APARATO PARA UTILIZAR LAS MEDIDAS DE ENERGIA DEL CUADRO PARA MEJORAR EL INDICE DE DETERMINACION.
    96.
    发明专利
    METODO Y APARATO PARA UTILIZAR LAS MEDIDAS DE ENERGIA DEL CUADRO PARA MEJORAR EL INDICE DE DETERMINACION. 未知

    公开(公告)号：MXPA01012654A

    公开(公告)日：2002-07-22

    申请号：MXPA01012654

    申请日：2000-06-09

    Applicant: QUALCOMM INC

    Inventor： LEVIN JEFFREY A

    IPC: H04L25/02

    Abstract: Un metodo y aparato Inalambrico de Division de Codigos de Acceso Multiple para determinar el indice recibido de una senal de voz/datos desde una estacion movil a una estacion base. Los vocodificadores de indice variable transmiten la voz en uno de varios indices de cuadro previamente determinados. El receptor determina el indice transmitido basado en un de varios parametros del cuadro. Uno de los parametros recibidos es la energia del cuadro. La energia del cuadro recibida es medida por la longitud de la porcion importante del cuadro. La energia es medida por la mitad del cuadro que puede contener solamente energia si es enviado un cuadro de indice total. Si la energia medida excede un umbral, entonces indica un indice completo. Tambien, la energia es medida por la cuarta parte de un cuadro que puede contener solamente energia, si se ha enviado un cuadro de medio indice. Si la energia excede un umbral, entonces es indicado un medio indice. El proceso se repite para los indices de un cuarto y un octavo.

    METHOD AND APPARATUS FOR DECODING MULTIPATH SIGNALS
    97.
    发明专利
    METHOD AND APPARATUS FOR DECODING MULTIPATH SIGNALS 未知

    公开(公告)号：HK1041123A1

    公开(公告)日：2002-06-28

    申请号：HK02102433

    申请日：2002-04-02

    Applicant: QUALCOMM INC

    Inventor： LEVIN JEFFREY A ,  RIDDLE CHRISTOPHER C ,  SHERMAN TOM B

    IPC: H04B1/7117 ,  H04B1/7115 ,  H04B1/712 ,  H04B7/26 ,  H04B

    Abstract: A wireless receiver receiving multipath Wash-code symbols determines which of fingers 402, 410 have locked on a signal. Measurements of the correlation energies between the received signal and all possible symbols are stored in energy storage units 404, 412. The actual signals are combined in combiner 408. A maximum determiner 416 determines the most likely combined symbol, and an index for this symbol is fed back to the energy storage units. Lock detectors 406, 414 use the measurement for this fed-back symbol to determine whether the finger has locked onto a path. This determination is used to decide whether the next signal detected by that finger should be applied to the combiner.

    99.
    发明专利
    未知

    公开(公告)号：ID30486A

    公开(公告)日：2001-12-13

    申请号：ID20011952

    申请日：2000-02-08

    Applicant: QUALCOMM INC

    Inventor： LEVIN JEFFREY A ,  RIDDLE CHRISTOPHER C ,  TOM SHERMAN

    IPC: H04B1/7085 ,  H04B1/707

    Abstract: In order to time track an incoming signal, a receiver demodulates a first instance of a signal to produce a first set of energy values corresponding to a set of possible data values of the signal. The receiver also demodulates a second instance of the signal to produce a second set of energy values corresponding to the set of possible data values. The receiver combines the first and the second sets of energy values to determine a combined set of energy values. The receiver determines a first estimate of a most likely transmitted data value based upon the combined set of energy values. The receiver decovers an early set of despread samples of the first instance using a symbol corresponding to the first estimate to produce a first early energy value. The receiver decovers a late set of despread samples of the first instance using the symbol corresponding to the first estimate to produce a first late energy value. Finally, the receiver determines a time offset of the first instance based upon the first early and the first late energy values.

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