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    73.
    发明专利
    未知

    公开(公告)号：AT352129T

    公开(公告)日：2007-02-15

    申请号：AT04025921

    申请日：2000-12-07

    Applicant: QUALCOMM INC

    Inventor： CHALLA RAGHU ,  BARGHOUTI IHAB

    IPC: H04B1/16 ,  H04W52/02 ,  H04Q7/32

    Abstract: A method and apparatus is described for tracking the length of a sleep period within a mobile station using a sleep clock to precisely calibrate portions of the sleep period. The sleep period subdivided into a sequence of sub-periods each of known duration wherein the durations of the sub-periods are not necessarily integer multiples of cycles of the sleep clock. Elapsed time is tracked within each individual sub-period of the sleep period using an integer sleep counter which tracks whole cycles of the sleep clock. Then any remaining fractional portions of the cycles of the sleep mode clock not accounted for by the integer sleep counter are tracked using a fractional sleep counter. The fractional sleep coutner accumulates remaining fractional portions of sleep mode cycles from one sub-period to the next. A method and apparatus is also described for estimating frequency drift with a sleep clock signal used during a slotted paging mode of operation of a wireless mobile station. An initial frequency of the sleep clock signal is determined following power-up of the mobile station. A fixed frequency drift compensation factor representative of a difference between the initial frequency of the sleep clock signal and a pre-determined nominal frequency is then determined. A dynamic frequency error compensation factor representative of a difference between the initial frequency and a current frequency of the slow clock signal is estimated. Then, throughout the slotted mode of operation, new values for the dynamic frequency compensation factor are iteratively determined by using a loop filter.

    Method and apparatus for tracking the length of a sleep period in a mobile station
    75.
    发明专利
    Method and apparatus for tracking the length of a sleep period in a mobile station 未知

    公开(公告)号：HK1074541A1

    公开(公告)日：2005-11-11

    申请号：HK05106018

    申请日：2005-07-14

    Applicant: QUALCOMM INC

    Inventor： CHALLA RAGHU ,  BARGHOUTI IHAB

    IPC: H04B20060101 ,  H04B1/16 ,  H04W52/02

    Abstract: A method and apparatus is described for tracking the length of a sleep period within a mobile station using a sleep clock to precisely calibrate portions of the sleep period. The sleep period subdivided into a sequence of sub-periods each of known duration wherein the durations of the sub-periods are not necessarily integer multiples of cycles of the sleep clock. Elapsed time is tracked within each individual sub-period of the sleep period using an integer sleep counter which tracks whole cycles of the sleep clock. Then any remaining fractional portions of the cycles of the sleep mode clock not accounted for by the integer sleep counter are tracked using a fractional sleep counter. The fractional sleep coutner accumulates remaining fractional portions of sleep mode cycles from one sub-period to the next. A method and apparatus is also described for estimating frequency drift with a sleep clock signal used during a slotted paging mode of operation of a wireless mobile station. An initial frequency of the sleep clock signal is determined following power-up of the mobile station. A fixed frequency drift compensation factor representative of a difference between the initial frequency of the sleep clock signal and a pre-determined nominal frequency is then determined. A dynamic frequency error compensation factor representative of a difference between the initial frequency and a current frequency of the slow clock signal is estimated. Then, throughout the slotted mode of operation, new values for the dynamic frequency compensation factor are iteratively determined by using a loop filter.

    SYSTEMS AND TECHNIQUES FOR CHANNEL GAIN COMPUTATIONS
    78.
    发明专利
    SYSTEMS AND TECHNIQUES FOR CHANNEL GAIN COMPUTATIONS 未知

    公开(公告)号：AU2002357235A1

    公开(公告)日：2003-06-30

    申请号：AU2002357235

    申请日：2002-12-12

    Applicant: QUALCOMM INC

    Inventor： BLACK PETER J ,  SINDHUSHAYANA NAGABHUSHANA ,  CHALLA RAGHU ,  ATTAR RASHID

    IPC: H04B7/005 ,  H04B7/00 ,  H04B1/00 ,  H04K1/00 ,  H04L27/30

    Abstract: Systems and techniques for controlling transmission power involve receiving a first to second channel power ratio, receiving a first to second channel power ratio, adjusting the power ratio if a combined power of a plurality of channels exceeds a threshold, the channels including the first and second channels, and computing gain of the first channel as a function of the power ratio. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

    Method and apparatus for compensating for frequency drift in a low frequency sleep clock within a mobile station operating in a slotted paging mode
    79.
    发明专利
    Method and apparatus for compensating for frequency drift in a low frequency sleep clock within a mobile station operating in a slotted paging mode 未知

    公开(公告)号：AU1954201A

    公开(公告)日：2002-06-18

    申请号：AU1954201

    申请日：2000-12-07

    Applicant: QUALCOMM INC

    Inventor： CHALLA RAGHU ,  BARGHOUTI IHAB

    IPC: H04B1/16 ,  H04W52/02 ,  H04Q7/32

    Abstract: A method and apparatus is described for tracking the length of a sleep period within a mobile station using a sleep clock to precisely calibrate portions of the sleep period. The sleep period subdivided into a sequence of sub-periods each of known duration wherein the durations of the sub-periods are not necessarily integer multiples of cycles of the sleep clock. Elapsed time is tracked within each individual sub-period of the sleep period using an integer sleep counter which tracks whole cycles of the sleep clock. Then any remaining fractional portions of the cycles of the sleep mode clock not accounted for by the integer sleep counter are tracked using a fractional sleep counter. The fractional sleep coutner accumulates remaining fractional portions of sleep mode cycles from one sub-period to the next. A method and apparatus is also described for estimating frequency drift with a sleep clock signal used during a slotted paging mode of operation of a wireless mobile station. An initial frequency of the sleep clock signal is determined following power-up of the mobile station. A fixed frequency drift compensation factor representative of a difference between the initial frequency of the sleep clock signal and a pre-determined nominal frequency is then determined. A dynamic frequency error compensation factor representative of a difference between the initial frequency and a current frequency of the slow clock signal is estimated. Then, throughout the slotted mode of operation, new values for the dynamic frequency compensation factor are iteratively determined by using a loop filter.

    MULTIPATH DOPPLER-ADJUSTED FREQUENCY TRACKING LOOP
    80.
    发明专利
    MULTIPATH DOPPLER-ADJUSTED FREQUENCY TRACKING LOOP 未知

    公开(公告)号：CA2397390A1

    公开(公告)日：2001-08-16

    申请号：CA2397390

    申请日：2001-01-26

    Applicant: QUALCOMM INC

    Inventor： ROH MARK ,  SIH GILBERT ,  BUTLER BRIAN ,  AGRAWAL AVNEESH ,  CHALLA RAGHU

    IPC: H04B1/712 ,  H04B1/7073 ,  H04B1/7087 ,  H04B1/7115 ,  H04B1/7117 ,  H04L27/00 ,  H04B1/707

    Abstract: A novel and improved method and apparatus for frequency tracking is describe d. Two main sources of error that contribute to the frequency difference betwee n locally generated carriers and those used to modulate received signals inclu de frequency offset between the two timing sources and doppler effects due to relative movement between the sources. The present invention provides a tracking mechanism for removing the effects of error due to frequency offset as well as compensation for frequency error due to doppler in a plurality of multipath signals. Each finger (700a..700n) of a RAKE receiver utilizing the present invention will compute a frequency error for that finger. The weight ed average of all of these frequency errors is calculated (710) and filtered (720) to provide a control signal for varying the frequency of IF and RF frequency synthesizers, accounting for the common frequency offset seen at each finger. Additionally, each finger is equipped with a rotator (706a...706n) for providing frequency adjustment specific to that finger. Th e frequency of each finger is adjusted through feedback of the frequency error finger.

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