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    2.
    发明专利
    未知

    公开(公告)号：AT376723T

    公开(公告)日：2007-11-15

    申请号：AT97944494

    申请日：1997-09-26

    Applicant: QUALCOMM INC

    Inventor： KREMM STEVEN ,  SKINNER GORDON

    IPC: H04B1/16 ,  H04B7/01 ,  H04B7/208

    Abstract: A method and apparatus for determining frequency offsets caused by oscillator error or Doppler effects in a user terminal (for example, a mobile wireless telephone) in a communication system. The system (100) includes at least one user terminal (124, 126) and a base station (112), or gateway (120, 122) for communicating with the user terminal (124, 126) through a satellite (116, 118) with predetermined known orbital positions or patterns. A communication signal (130, 132, 146, 148) is precorrected for known Doppler effects, such as between a gateway and a transferring satellite (146, 148), when used, and transmitted to a user terminal. The user terminal (124, 126) determines the signal frequency relative to a reference oscillator (240), and treats any detected difference as resulting completely from Doppler. The frequency difference is either transferred as data in reverse link transmissions (130, 132, 140, 142), or used as a pre-correction factor for such transmissions. The frequency of the reverse link user terminal signals is measured at the gateway (120, 122), again compensating for known Doppler effects, to provide a nominal error measurement. Measured frequency error or offsets are then divided in half to arrive at a Doppler shift error, or divided in half and scaled to the appropriate frequency to arrive at a user terminal oscillator error. The detected error can be transmitted to the user terminal (124, 126) for use in correcting the oscillator output frequency, or for adjusting the timing of, or time tracking for, the user terminal (124, 126). Alternatively, the detected error can be included as data in subsequent signals for use by gateways (120, 122) or base stations (112).

    3.
    发明专利
    未知

    公开(公告)号：NO20001819L

    公开(公告)日：2000-06-08

    申请号：NO20001819

    申请日：2000-04-07

    Applicant: QUALCOMM INC

    Inventor： HARMS BRIAN ,  BUTLER BRIAN ,  SKINNER GORDON

    IPC: H04J13/12 ,  H04B1/707 ,  H04B1/7075 ,  H04B1/7077 ,  H04B7/216 ,  H04J13/00

    Abstract: A technique for spreading information signals in a spread spectrum communication system to provide increased signal acquisition speed. A first PN spreading code or code set is used to spread information signals along with a second PN spreading code sequence or function. The second PN code is synchronized with the first PN spreading code, but has a larger code period so that each code chip of the second PN code extends over the entire period of the first PN code. The longer period spreading code forms an outer code which helps provide unambiguous beam identification and easily acquired frame timing in the presence of dynamically changing signal path delay, improving signal acquisition.

    4.
    发明专利
    未知

    公开(公告)号：NO20001819D0

    公开(公告)日：2000-04-07

    申请号：NO20001819

    申请日：2000-04-07

    Applicant: QUALCOMM INC

    Inventor： HARMS BRIAN ,  BUTLER BRIAN ,  SKINNER GORDON

    IPC: H04J13/12 ,  H04B1/707 ,  H04B1/7075 ,  H04B1/7077 ,  H04B7/216 ,  H04J13/00 ,  H04B

    Abstract: A technique for spreading information signals in a spread spectrum communication system to provide increased signal acquisition speed. A first PN spreading code or code set is used to spread information signals along with a second PN spreading code sequence or function. The second PN code is synchronized with the first PN spreading code, but has a larger code period so that each code chip of the second PN code extends over the entire period of the first PN code. The longer period spreading code forms an outer code which helps provide unambiguous beam identification and easily acquired frame timing in the presence of dynamically changing signal path delay, improving signal acquisition.

    Code acquisition in a cdma communication system using multiple walsh channels
    5.
    发明专利
    Code acquisition in a cdma communication system using multiple walsh channels 未知

    公开(公告)号：AU700456B2

    公开(公告)日：1999-01-07

    申请号：AU6635696

    申请日：1996-06-28

    Applicant: QUALCOMM INC

    Inventor： SKINNER GORDON ,  HARMS BRIAN

    IPC: H04L27/32 ,  B60R11/00 ,  B60R11/02 ,  B60R11/04 ,  H04B1/7075 ,  H04B1/7077 ,  H04B1/707

    Abstract: A technique for using energy received by subscriber units over multiple orthogonal channels within a spread spectrum communication system to acquire signal timing by controlling signal amplitude integration intervals used in detecting such timing. Received signals are despread and respective amplitudes integrated over periods that are divisible by factors of 2 into the length of Walsh functions used to generate orthogonal signal channels. Non-coherent combinations of the results of this integration are subsequently formed over periods that commence and terminate on Walsh function boundaries, and used to determine when a correct time offset has been selected for despreading signals. Additional advantages are realized by assigning signals that consistently provide a higher energy content such as paging, synchronization, and most frequently assigned traffic channels to specific orthogonal channels within the communication system. In exemplary embodiments, Walsh functions of length 128 are used as channelizing codes and a pilot signal is assigned to channel 0. This results in traffic channels or paging and synchronization functions being assigned to channel 64 when the integration periods are 64 chips long, and to channels 32, 64, and 96 when the periods are 32 chips long. In this manner, additional energy is available during the integration process for use in determining when correct signal acquisition timing offsets have been selected, without the use of additional hardware.

    6.
    发明专利
    未知

    公开(公告)号：DE69614348T2

    公开(公告)日：2002-06-13

    申请号：DE69614348

    申请日：1996-06-28

    Applicant: QUALCOMM INC

    Inventor： SKINNER GORDON ,  HARMS BRIAN

    IPC: H04L27/32 ,  B60R11/00 ,  B60R11/02 ,  B60R11/04 ,  H04B1/7075 ,  H04B1/7077 ,  H04B1/707

    Abstract: A technique for using energy received by subscriber units over multiple orthogonal channels within a spread spectrum communication system to acquire signal timing by controlling signal amplitude integration intervals used in detecting such timing. Received signals are despread and respective amplitudes integrated over periods that are divisible by factors of 2 into the length of Walsh functions used to generate orthogonal signal channels. Non-coherent combinations of the results of this integration are subsequently formed over periods that commence and terminate on Walsh function boundaries, and used to determine when a correct time offset has been selected for despreading signals. Additional advantages are realized by assigning signals that consistently provide a higher energy content such as paging, synchronization, and most frequently assigned traffic channels to specific orthogonal channels within the communication system. In exemplary embodiments, Walsh functions of length 128 are used as channelizing codes and a pilot signal is assigned to channel 0. This results in traffic channels or paging and synchronization functions being assigned to channel 64 when the integration periods are 64 chips long, and to channels 32, 64, and 96 when the periods are 32 chips long. In this manner, additional energy is available during the integration process for use in determining when correct signal acquisition timing offsets have been selected, without the use of additional hardware.

    7.
    发明专利
    未知

    公开(公告)号：AT204104T

    公开(公告)日：2001-08-15

    申请号：AT96926056

    申请日：1996-06-28

    Applicant: QUALCOMM INC

    Inventor： SKINNER GORDON ,  HARMS BRIAN

    IPC: H04L27/32 ,  B60R11/00 ,  B60R11/02 ,  B60R11/04 ,  H04B1/7075 ,  H04B1/7077 ,  H04B1/707

    Abstract: A technique for using energy received by subscriber units over multiple orthogonal channels within a spread spectrum communication system to acquire signal timing by controlling signal amplitude integration intervals used in detecting such timing. Received signals are despread and respective amplitudes integrated over periods that are divisible by factors of 2 into the length of Walsh functions used to generate orthogonal signal channels. Non-coherent combinations of the results of this integration are subsequently formed over periods that commence and terminate on Walsh function boundaries, and used to determine when a correct time offset has been selected for despreading signals. Additional advantages are realized by assigning signals that consistently provide a higher energy content such as paging, synchronization, and most frequently assigned traffic channels to specific orthogonal channels within the communication system. In exemplary embodiments, Walsh functions of length 128 are used as channelizing codes and a pilot signal is assigned to channel 0. This results in traffic channels or paging and synchronization functions being assigned to channel 64 when the integration periods are 64 chips long, and to channels 32, 64, and 96 when the periods are 32 chips long. In this manner, additional energy is available during the integration process for use in determining when correct signal acquisition timing offsets have been selected, without the use of additional hardware.

    MULTI-LAYERED PN CODE SPREADING IN A MULTI-USER COMMUNICATIONS SYSTEM
    10.
    发明专利
    MULTI-LAYERED PN CODE SPREADING IN A MULTI-USER COMMUNICATIONS SYSTEM 未知

    公开(公告)号：CA2305718A1

    公开(公告)日：1999-04-22

    申请号：CA2305718

    申请日：1998-10-09

    Applicant: QUALCOMM INC

    Inventor： SKINNER GORDON ,  BUTLER BRIAN ,  HARMS BRIAN

    IPC: H04J13/12 ,  H04B1/707 ,  H04B1/7075 ,  H04B1/7077 ,  H04B7/216 ,  H04J13/00

    Abstract: A technique for spreading information signals in a spread spectrum communication system to provide increased signal acquisition speed. A first PN spreading code or code set is used to spread information signals along with a second PN spreading code sequence or function. The second PN code is synchronized with the first PN spreading code, but has a larger code period so that each code chip of the second PN code extends over the entire period of the first PN code. The longer period spreading code forms an outer code which helps provide unambiguous beam identification and easily acquired frame timing in the presence of dynamically changing signal path delay, improving signal acquisition.

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