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    INTERFERENCE SUPPRESSION IN CDMA SYSTEMS
    3.
    发明专利
    INTERFERENCE SUPPRESSION IN CDMA SYSTEMS 未知

    公开(公告)号：CA2169961C

    公开(公告)日：1999-02-23

    申请号：CA2169961

    申请日：1994-09-15

    Applicant: BELL COMMUNICATIONS RES

    Inventor： HONIG MICHAEL LATHAM ,  MADHOW UPAMANYU

    IPC: H03H21/00 ,  H03H17/00 ,  H04B1/12 ,  H04B1/7103 ,  H04B3/06 ,  H04B7/005 ,  H04J13/04 ,  H04B15/00

    Abstract: Circuitry and concomitant methodology for demodulating Direct-Sequence, Spread-Spectrum Code-Division Multiple-Access (DS/SS CDMA) channel signal using multiple samples per transmitted symbol and a minimum mean squared error criterion to suppress interference. In one embodiment, a bank of cyclically shifted filters (502) determined with reference to the conventional matched filter (401) for CDMA is used to demodulate the channel signal. In another embodiment, a bank of sub-filters (601, 602) determined with reference to the conventional matched filter (401) for CDMA is employed to demodulate the channel signal. In yet another embodiment, the output of a conventional matched filter is oversampled to demodulate the channel signal. Each embodiment utilizes a set of adaptive coefficients selected to minimize the mean square error between the transmitted symbol and detected symbol.

    A SPREAD-TIME CODE DIVISION MULTIPLE ACCESS TECHNIQUE WITH ARBITRARY SPECTRAL SHAPING
    4.
    发明专利
    A SPREAD-TIME CODE DIVISION MULTIPLE ACCESS TECHNIQUE WITH ARBITRARY SPECTRAL SHAPING 未知

    公开(公告)号：CA2123488C

    公开(公告)日：1999-01-05

    申请号：CA2123488

    申请日：1992-10-21

    Applicant: BELL COMMUNICATIONS RES

    Inventor： CRESPO PEDRO MIGUEL ,  HONIG MICHAEL LATHAM ,  SALEHI JAWAD AHMAD

    IPC: H04B15/00 ,  H04J13/00 ,  H04L5/02

    Abstract: A spread-time code division multiple access (ST-CDMA) technique is disclosed for bandlimited access to a channel. With ST-CDMA, pseudo-random (PN) sequences are assigned to each transmitter in the mu lti-transmitter system, and the Fourier transform (110) of the transmitter pulse for a given transmitter is determined b y modulating (120) the phase of the desired transmitter spectrum by the PN sequence (160) assigned to the transmitter. The data symbol ( 180) produced by the transmitter are conveyed by delayed versions of the transmitter pulse. The transmitted data (151) for a p articular transmitter is recovered at a receiver synchronized to the transmitter by sampling the output of a filter matched to th e corresponding pulse.

    5.
    发明专利
    未知

    公开(公告)号：DE69229277T2

    公开(公告)日：1999-12-30

    申请号：DE69229277

    申请日：1992-10-21

    Applicant: BELL COMMUNICATIONS RES

    Inventor： CRESPO PEDRO MIGUEL ,  HONIG MICHAEL LATHAM ,  SALEHI JAWAD

    IPC: H04J13/00 ,  H04L5/02 ,  H04B15/00 ,  H04B14/02 ,  H04J9/00 ,  H04K1/02

    Abstract: A spread-time code division multiple access (ST-CDMA) technique is disclosed for bandlimited access to a channel. With ST-CDMA, pseudo-random (PN) sequences are assigned to each transmitter in the multi-transmitter system, and the Fourier transform of the transmitter pulse for a given transmitter is determined by modulating the phase of the desired transmitter spectrum by the PN sequence assigned to the transmitter. The data symbols produced by the transmitter are conveyed by delayed versions of the transmitter pulse. The transmitted data for a particular transmitter is recovered at a receiver synchronized to the transmitter by sampling the output of a filter matched to the corresponding transmitter pulse.

    6.
    发明专利
    未知

    公开(公告)号：DE69229277D1

    公开(公告)日：1999-07-01

    申请号：DE69229277

    申请日：1992-10-21

    Applicant: BELL COMMUNICATIONS RES

    Inventor： CRESPO PEDRO MIGUEL ,  HONIG MICHAEL LATHAM ,  SALEHI JAWAD

    IPC: H04J13/00 ,  H04L5/02 ,  H04B15/00 ,  H04B14/02 ,  H04J9/00 ,  H04K1/02

    Abstract: A spread-time code division multiple access (ST-CDMA) technique is disclosed for bandlimited access to a channel. With ST-CDMA, pseudo-random (PN) sequences are assigned to each transmitter in the multi-transmitter system, and the Fourier transform of the transmitter pulse for a given transmitter is determined by modulating the phase of the desired transmitter spectrum by the PN sequence assigned to the transmitter. The data symbols produced by the transmitter are conveyed by delayed versions of the transmitter pulse. The transmitted data for a particular transmitter is recovered at a receiver synchronized to the transmitter by sampling the output of a filter matched to the corresponding transmitter pulse.

    Interference Suppression in CDMA Systems
    7.
    发明专利
    Interference Suppression in CDMA Systems 未知

    公开(公告)号：CA2169961A1

    公开(公告)日：1995-03-30

    申请号：CA2169961

    申请日：1994-09-15

    Applicant: BELL COMMUNICATIONS RES

    Inventor： HONIG MICHAEL LATHAM ,  MADHOW UPAMANYU

    IPC: H03H21/00 ,  H03H17/00 ,  H04B1/12 ,  H04B1/7103 ,  H04B3/06 ,  H04B7/005 ,  H04J13/04 ,  H04B15/00

    Abstract: Circuitry and concomitant methodology for demodulating Direct-Sequence, Spread-Spectrum Code-Division Multiple-Access (DS/SS CDMA) channel signal using multiple samples per transmitted symbol and a minimum mean squared error criterion to suppress interference. In one embodiment, a bank of cyclically shifted filters determined with reference to the conventional matched filter for CDMA is used to demodulate the channel signal. In another embodiment, a bank of sub-filters determined with reference to the conventional matched filter for CDMA is employed to demodulate the channel signal. In yet another embodiment, the output of a conventional matched filter is oversampled to demodulate the channel signal. Each embodiment utilizes a set of adaptive coefficients selected to minimize the mean square error between the transmitted symbol and detected symbol.

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