中科微点-全球专利检索

  1. Login
  2. Sign Up

Search Results

100 records (took 0.022 seconds)

    METHOD AND DEVICE FOR DEMODULATION IN SPREAD SPECTRUM COMMUNICATION SYSTEM AND POWER CONTROL BIT DETECTION
    1.
    发明专利
    METHOD AND DEVICE FOR DEMODULATION IN SPREAD SPECTRUM COMMUNICATION SYSTEM AND POWER CONTROL BIT DETECTION 失效

    公开(公告)号：JPH1032560A

    公开(公告)日：1998-02-03

    申请号：JP9014997

    申请日：1997-03-25

    Applicant: MOTOROLA INC

    Inventor： LING FUYUN ,  BORTH DAVID E ,  FRANK COLIN D ,  RASKY PHILLIP D ,  KEPLER JAMES F

    IPC: H04B1/707 ,  H04B7/005 ,  H04B7/26 ,  H04J11/00 ,  H04J13/00 ,  H04L25/02

    Abstract: PROBLEM TO BE SOLVED: To attain improved demodulation for a spread spectrum communication signal including quick and accurate detection of a power control bit in a spread spectrum system. SOLUTION: A receiver circuit 400 receives a spread spectrum communication signal such as a DS-CDMA signal and conducts inverse spread processing and decoding. A channel phase and a channel gain for a communication channel are estimated from a pilot symbol of a pilot channel. The estimated value is provide to a demodulator 422 to demodulate a symbol of a traffic channel. Furthermore, a channel phase and a channel gain for a power control identifier are estimated from a pilot symbol. The estimated value is provided to a demodulator 424 to demodulate the power control identifier. The traffic channel symbol is delayed by a prescribed time in a delay element 420 before the demodulation. The power control identifier is delayed at a short delay element 418 or not delayed at all before demodulation.

    DS-CDMA RECEIVER AND FORWARD LINK DIVERSITY METHOD
    2.
    发明专利
    DS-CDMA RECEIVER AND FORWARD LINK DIVERSITY METHOD 失效

    公开(公告)号：JPH11154896A

    公开(公告)日：1999-06-08

    申请号：JP25044498

    申请日：1998-08-20

    Applicant: MOTOROLA INC

    Inventor： KELTON JAMES R ,  RASKY PHILLIP D

    IPC: H04B7/08 ,  H04B7/26 ,  H04L1/06 ,  H04B1/707

    Abstract: PROBLEM TO BE SOLVED: To provide an improved device and a method for the diversity of a mobile station receiver in a DS-CDMA system. SOLUTION: A mobile station 104 in a DS-CDMA communication system 100 has receiver diversity. A first antenna 130 receives a signal from a base station 102 via a communication channel 101. A second antenna 132 receives a signal, and this signal is delayed just of the time of one or more chips by a delay element 142 and combined with a signal from the first antenna by an adder 148. A combined signal is provided to a rake receiver 112 for decoding and demodulation. When recognizable or identifiable multi-path energy exists up to a point which is not to be dealt with by a rake receiver finger to which most of received signal energy has been allocated, the second antenna is disconnected to prevent the increase in the interfering level.

    COMMUNICATIONS DEVICE AND METHOD FOR INTERFERENCE SUPPRESSION IN DS-CDMA SYSTEM
    3.
    发明专利
    COMMUNICATIONS DEVICE AND METHOD FOR INTERFERENCE SUPPRESSION IN DS-CDMA SYSTEM 失效

    公开(公告)号：JPH11261531A

    公开(公告)日：1999-09-24

    申请号：JP36899098

    申请日：1998-12-25

    Applicant: MOTOROLA INC

    Inventor： MADHOW UPAMANYU ,  FRANK COLIN D ,  RASKY PHILLIP D

    IPC: H03M7/30 ,  G06F17/14 ,  H04B1/10 ,  H04B1/707 ,  H04B1/7107 ,  H04B1/7115 ,  H04B7/26 ,  H04J13/04

    Abstract: PROBLEM TO BE SOLVED: To provide a method and a device to completely suppress an interference vector in a DS-CDMA communications system. SOLUTION: Receiving branches 1 to 4 are allocated to a multi-path from both a sector that performs soft handoff and a sector that does not perform soft handoff (404 and 406). The set of a traffic channel included in a sector signal is decided for each receiving circuit (410). Interference is classified according to a prescribed interference condition for each receiving circuit (412). A set of interference vectors is selected from a classifying list of interference (414) and a desired code of a receiver or orthogonal projection of a Walsh code is calculated (416). Next, the receiving circuit inversely spreads received data by utilizing the orthogonal projection in its correlating device (418).

    LAKE RECEIVER AND FINGER MANAGING METHOD FOR SPREAD SPECTRUM COMMUNICATION
    4.
    发明专利
    LAKE RECEIVER AND FINGER MANAGING METHOD FOR SPREAD SPECTRUM COMMUNICATION 失效

    公开(公告)号：JPH11168448A

    公开(公告)日：1999-06-22

    申请号：JP27432698

    申请日：1998-09-10

    Applicant: MOTOROLA INC

    Inventor： LAROSA CHRISTOPHER P ,  CARNEY MICHAEL J ,  BECKER CHRISTOPHER J ,  EBERHARDT MICHAEL A ,  FRANK COLIN D ,  RASKY PHILLIP D

    IPC: H04B1/7113 ,  H04B1/7115 ,  H04B1/7117 ,  H04J13/00

    Abstract: PROBLEM TO BE SOLVED: To provide a lake receiver and a finger managing method improved for providing the merit of path diversity even when the interval of multipath radio waves is shorter than one-chip time. SOLUTION: A lake receiver 112 is provided with plural fingers 122, 124 and 128. Each finger is provided with a demodulator for demodulating the radio waves of multiple path signals and a time tracking circuit for controlling the timewise position of the finger based on the timewise position of the radio wave. Low delay spreading conditions are detected, the positions of two adjacent fingers are controlled and fingers more than two are prevented from being converged around a common timewise position. By maintaining the timing intervals of fingers, even during low delay spreading conditions, the path diversity is effectively utilized by the lake receiver 112 and the performance of the receiver is improved.

    8.
    发明专利
    未知

    公开(公告)号：FI115429B

    公开(公告)日：2005-04-29

    申请号：FI981939

    申请日：1998-09-09

    Applicant: MOTOROLA INC

    Inventor： LAROSA CHRISTOPHER P ,  CARNEY MICHAEL J ,  BECKER CHRISTOPHER J ,  EBERHARDT MICHAEL A ,  FRANK COLIN D ,  RASKY PHILLIP D

    IPC: H04B1/7113 ,  H04B1/7115 ,  H04B1/7117 ,  H04B1/69

    Abstract: A RAKE receiver (112) includes a plurality of fingers (122, 124, 126, 128). Each finger includes a demodulator (402) for demodulating a ray of a multipath signal and a time tracking circuit (404) for controlling the time position of the finger in accordance with time position of the ray. A low delay-spread condition is detected and the positions of two adjacent fingers are controlled to prevent convergence of two or more fingers about a common time position. By maintaining finger timing separation, path diversity is exploited by the RAKE receiver even during the low delay-spread condition to improve receiver performance.

    9.
    发明专利
    未知

    公开(公告)号：FR2767992B1

    公开(公告)日：2003-03-14

    申请号：FR9810606

    申请日：1998-08-21

    Applicant: MOTOROLA INC

    Inventor： KELTON JAMES ,  RASKY PHILLIP D

    IPC: H04B7/08 ,  H04B7/26 ,  H04L1/06 ,  H04B7/216 ,  H04B7/02 ,  H04Q7/22 ,  H04B1/707

    Abstract: A mobile station (104) in a DS-CDMA communication system (100) has receiver diversity. A first antenna (130) receives signals over a communications channel (101) from a base station (102). A second antenna (132) receives signals which are delayed in a delay element (142) by one or more chip times and combined in a summer (148) with signals from the first antenna. The combined signals are presented to a RAKE receiver (112) for decoding and demodulation. When discernible multipath energy is present to the point where much of the received signal energy is not accounted for in the assigned RAKE receiver fingers, the second antenna is switched out to avoid increasing the level of interference.

    Communication device and method for interference suppression in a ds-cdma system
    10.
    发明专利
    Communication device and method for interference suppression in a ds-cdma system 未知

    公开(公告)号：GB2333013B

    公开(公告)日：2003-01-08

    申请号：GB9827917

    申请日：1998-12-21

    Applicant: MOTOROLA INC

    Inventor： MADHOW UPAMANYU ,  FRANK COLIN D ,  RASKY PHILLIP D

    IPC: H03M7/30 ,  G06F17/14 ,  H04B1/10 ,  H04B1/707 ,  H04B1/7107 ,  H04B1/7115 ,  H04B7/26

    Abstract: Method and apparatus for completely suppressing interference vectors in a DS-CDMA communication system (100). Receiver circuits (122, 124, 126, 128) are assigned (404, 406) to multipath from sectors both in soft handoff and not in soft handoff with the receiver. For each receiver circuit, a set of traffic channels present on the sector's signal is determined (410). For each receiver circuit, the interference is ranked (412) according to predetermined interference criteria. A set of interference vectors is selected (414) from the ranked lists of interference and an orthogonal projection is computed (416) of the receiver's desired code or Walsh code relative to the selected set of interference vectors. The receiver circuit then uses the orthogonal projection in its correlator to despread (418) received data.

Patent Agency Ranking