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    FINE TIMING ACQUISITION
    71.
    发明专利
    FINE TIMING ACQUISITION 未知

    公开(公告)号：CA2600561A1

    公开(公告)日：2006-09-21

    申请号：CA2600561

    申请日：2006-03-10

    Applicant: QUALCOMM INC

    Inventor： MURTHY VINAY ,  KRISHNAMOORTHI RAGHURAMAN ,  LING FUYUN ,  VRCELJ BOJAN

    IPC: H04L27/26

    Abstract: A method for synchronizing timing of a receiver to a received orthogonal frequency division multiplexing (OFDM) signal is disclosed. A first timing acquisition is performed with a first received time division multiplexed (TDM) pilot to determine a course timing estimate of the received OFDM signal. A second timing acquisition is performed with a second TDM pilot to determine a fine timing estimate for a OFDM symbol of the received OFDM signal. In the second timing acquisition, the accumulated energy of channel taps over a detection window is determined and a trailing edge of the accumulated energy curve is detected. A Fourier transform (FT) collection window location for subsequent OFDM symbols is adjusted according to the trailing edge information.

    SYMBOL TIMING CORRECTIONS IN A MULTI CARRIER SYSTEM BY USINGTHE CHANNEL ESTIMATION
    72.
    发明专利
    SYMBOL TIMING CORRECTIONS IN A MULTI CARRIER SYSTEM BY USINGTHE CHANNEL ESTIMATION 未知

    公开(公告)号：CA2600437A1

    公开(公告)日：2006-09-21

    申请号：CA2600437

    申请日：2006-03-10

    Applicant: QUALCOMM INC

    Inventor： VRCELJ BOJAN ,  MANTRAVADI ASHOK ,  LING FUYUN ,  MUKKAVILLI KIRAN

    IPC: H04L25/02 ,  H04L27/26

    Abstract: Systems and methods are provided for determining and applying timing corrections in a digital communications system. In an aspect, a timing correction method is provided for a multi-carrier system. This includes aligning two or more symbols with respect to each other from a symbol subset in order to account for timing differences between the symbols. The symbol alignment is first carried out to generate channel estimates for data demodulation. The channel estimates, thus generated, along with the timing alignment information are in turn used for determining timing corrections-to be applied to future symbols.

    ITERATIVE CHANNEL AND INTERFERENCE ESTIMATION AND DECODING
    73.
    发明专利
    ITERATIVE CHANNEL AND INTERFERENCE ESTIMATION AND DECODING 未知

    公开(公告)号：CA2558229A1

    公开(公告)日：2005-09-15

    申请号：CA2558229

    申请日：2005-02-25

    Applicant: QUALCOMM INC

    Inventor： KHANDEKAR AAMOD ,  AGRAWAL AVNEESH ,  LING FUYUN

    IPC: H04L25/03 ,  H04L1/00

    Abstract: For an iterative channel and interference estimation and decoding scheme, prior information for channel gain and interference is initially obtained based on received pilot symbols. Forward information for code bits corresponding to received data symbols is derived based on the received data symbols and the prior information and then decoded to obtain feedback information for the code bits corresponding to the received data symbols. A posteriori information for channel gain and interference for each received data symbol is derived based on the feedback information for that received data symbol. The a posteriori information for the received data symbols and the prior information are combined to obtain updated information for channel gain and interference for each received data symbol. The process can be repeated for any number of iterations. The prior, a posteriori, and updated information may be represented by joint probability distributions on channel gain and interference. The forward and feedback information may be represented by log-likelihood ratios.

    LOCAL AND WIDE-AREA TRANSMISSIONS IN A WIRELESS BROADCAST NETWORK
    75.
    发明专利
    LOCAL AND WIDE-AREA TRANSMISSIONS IN A WIRELESS BROADCAST NETWORK 未知

    公开(公告)号：CA2543415A1

    公开(公告)日：2005-05-12

    申请号：CA2543415

    申请日：2004-10-22

    Applicant: QUALCOMM INC

    Inventor： WALKER KENT G ,  MANTRAVADI ASHOK ,  MURALI RAMASWAMY ,  LING FUYUN ,  SUBRAMANIAM ANAND D ,  VIJAYAN RAJIV

    IPC: H04L12/18 ,  H04L12/56 ,  H04W74/04 ,  H04W88/08

    Abstract: A method of broadcasting data in a wireless broadcast network, comprising multiplexing data for a wide-area transmission onto a first transmission span, the wide-area transmission being sent from a plurality of transmitters in the network; multiplexing data for a local transmission onto a second transmission span, wherein the multiplexing is onto frequency subbands pseudo-randomly selected from among all usable frequency subbands and the local transmission being sent from a subset of the plurality of transmitters; selecting the first and second transmission spans based on an amount of data to broadcast for the wide-area transmission and an amount of data to broadcast for the local transmission; and broadcasting the local and wide-area transmissions via a wireless link, wherein the data for the wide-area transmission and the data for the local transmission are time division multiplexed (TDM) at each base station, and wherein the first and second transmission spans are first and second time segments, respectively, of a frame of a predetermined time duration as well as a corresponding system.

    Method and device for performing demodulation of information signal
    76.
    发明专利
    Method and device for performing demodulation of information signal 未知

    公开(公告)号：HK1060669A1

    公开(公告)日：2004-08-13

    申请号：HK04103465

    申请日：2004-05-17

    Applicant: QUALCOMM INC

    Inventor： LING FUYUN

    IPC: H04B1/7085 ,  H04B1/7115 ,  H04B7/005 ,  H04L25/02 ,  H04Q7/38 ,  H04L ,  H04B

    Abstract: Apparatus for a transmitter and a receiver which enhance the performance of a system coherent demodulation by utilizing non-pilot sub-channels to enhance the accuracy of estimates of amplitude and phase noise inherent in the transmission channel is described. This enhancement is accomplished by utilizing the corrected received data on a fundamental channel to enhance a pilot channel estimate, which is subsequently utilized by a dot product module in demodulating a supplementary data channel.

    77.
    发明专利
    未知

    公开(公告)号：NO20092777L

    公开(公告)日：2003-09-12

    申请号：NO20092777

    申请日：2009-07-28

    Applicant: QUALCOMM INC

    Inventor： CHEN TAO ,  HOLTZMAN JACK M ,  LING FUYUN ,  SAINTS KEITH ,  WHEATLEY CHARLES E ,  SINDHUSHAYANA NAGABHUSHANA

    IPC: H04J13/00 ,  B21D31/04 ,  B21D39/08 ,  B21D39/20 ,  E21B23/08 ,  E21B29/10 ,  E21B43/10 ,  H04W52/12

    Abstract: An expander for radially expanding a tubular element by axial movement of the expander through the tubular element is provided. The expander comprising an expander member having a front part of a first cross-sectional size; a rear part of a second cross-sectional size larger than the first cross-sectional size; and an intermediate part arranged between said front part; and, rear part and having a cross-sectional size varying between said first and second cross-sectional sizes. The expander member is provided with fluid supply means for supplying pressurized fluid to the inner surface of the tubular element at a location opposite the intermediate part when the expander member is arranged in the tubular element.

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