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    71.
    发明专利
    未知

    公开(公告)号：AT441981T

    公开(公告)日：2009-09-15

    申请号：AT02768894

    申请日：2002-09-24

    Applicant: QUALCOMM INC

    Inventor： SMEE JOHN E ,  FERNANDEZ-CORBATON IVAN JESUS ,  JAYARAMAN SRIKANT

    IPC: H04B7/00 ,  H04B7/005 ,  H04B3/06 ,  H04L25/03

    Abstract: Systems and methods according to the present invention are described for adjusting the number of taps in an adaptive equalizer over time as the rate of change of a communications channel varies. The number of taps or "equalizer length" is adjusted based on an estimate of the Doppler frequency between the devices communicating over a channel. The Doppler frequency is reflective of the rate of change of the communications channel. Greater Doppler frequencies indicate a more quickly varying channel, and vice versa. It is therefore desirable to change the equalizer length (by adding or dropping taps) based on a measurement of the Doppler frequency. Equalizer length is increased as the Doppler frequency decreases. Conversely, equalizer length is decreased as the Doppler frequency increases. This enables the equalizer to achieve a better compromise between the competing goals of adaptation speed (less taps) and ISI reduction (more taps).

    72.
    发明专利
    未知

    公开(公告)号：BRPI0512050A

    公开(公告)日：2008-02-06

    申请号：BRPI0512050

    申请日：2005-06-14

    Applicant: QUALCOMM INC

    Inventor： BLACK PETER J ,  XU HAO ,  NAMGOONG JUNE ,  JAYARAMAN SRIKANT

    IPC: H04L25/02

    Abstract: A pilot assisted channel estimation process. A receiver may be configured to estimate the impulse response of a channel from a signal having pilot tones and spread-spectrum pilot signals. The receiver estimates the response of the channel from the pilot tones, and adapts the length of delay the channel response is estimated based on the spread-spectrum pilot signals.

    SYSTEMS AND METHODS FOR ADAPTIVELY ALLOCATING RESOURCES BETWEEN A DEDICATED REFERENCE SIGNAL AND A TRAFFIC SIGNAL
    73.
    发明专利
    SYSTEMS AND METHODS FOR ADAPTIVELY ALLOCATING RESOURCES BETWEEN A DEDICATED REFERENCE SIGNAL AND A TRAFFIC SIGNAL 未知

    公开(公告)号：HK1099459A1

    公开(公告)日：2007-08-10

    申请号：HK07106423

    申请日：2007-06-14

    Applicant: QUALCOMM INC

    Inventor： FERNANDEZ-CORBATON IVAN JESUS ,  JAYARAMAN SRIKANT ,  SWEET CHARLES WHEELER III

    IPC: H04W72/08

    Abstract: Systems and methods for adaptively allocating resources between a dedicated reference signal and a traffic signal are disclosed. In an exemplary embodiment, a wireless communication system 100 includes a base station 404. The base station 404 includes a receiver 428 that receives a quality metric 432 from a remote station 106. The quality metric 432 indicates the quality of a signal transmitted from the base station 404 and received by the remote station 106. The base station 404 also includes a resource allocation component 434 that uses the quality metric 432 to allocate a resource between the traffic signal 422 and the dedicated reference signal 418. The base station 404 also includes a transmitter 426 that transmits the traffic signal 422 and the dedicated reference signal 418 to the remote station 106.

    77.
    发明专利
    未知

    公开(公告)号：DE60214847D1

    公开(公告)日：2006-11-02

    申请号：DE60214847

    申请日：2002-05-31

    Applicant: QUALCOMM INC

    Inventor： CORBATON JESUS ,  SMEE E ,  JAYARAMAN SRIKANT

    IPC: H04B1/707 ,  H04L1/20 ,  H04L25/03

    Abstract: Method and apparatus that compensates for overestimation of channel SINR due to overfitting of an adaptive equalizer to the pilot portion of a received frame. The SINR of a wireless channel is estimated by adapting an adaptive equalizer using the pilot portion of the frame, applying the adaptive equalizer to a non-pilot portion of the frame, determining a parameter using the adaptive equalizer output, and estimating the SINR of the wireless channel using the parameter. The parameter can include, for example, the mean square error (MSE) or the bias of the equalizer output. The accuracy of the SINR estimate according to this aspect of the present invention is thereby improved (as compared to a SINR estimate based on parameters calculated during the pilot interval) because the adaptive equalizer is not overfit to the control or data portions of the frame.

    79.
    发明专利
    未知

    公开(公告)号：BRPI0407686A

    公开(公告)日：2006-03-01

    申请号：BRPI0407686

    申请日：2004-02-23

    Applicant: QUALCOMM INC

    Inventor： JAYARAMAN SRIKANT ,  SMEE JOHN E ,  FERNANDEZ-CORBATON IVAN JESUS

    IPC: H04B7/005 ,  H04B7/02 ,  H04L25/03

    Abstract: Techniques for performing equalization of multiple signals received by a terminal in soft handoff with multiple base stations. The received signal at the terminal is conditioned and digitized to provide a stream of received samples (y m ), which is then equalized/filtered (410) with multiple sets of coefficients to provide multiple streams of transmit chip estimates (X k ). One set of coefficients (f k ) is provided for each base station and is used to provide a corresponding stream of transmit chip estimates. The multiple streams of transmit chip estimates are further processed (420) to provide multiple streams of data symbol estimates (d k ), one stream of data symbol estimates for each base station. The multiple streams of data symbol estimates are then scaled (430) with multiple scaling factors (± k ) and combined (432) to provide a stream of combined data symbol estimates (d k ). The processing for the multiple base stations may be performed by a single hardware unit in a time division multiplexed manner.

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