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    BURST EXCITED LINEAR PREDICTION
    54.
    发明专利
    BURST EXCITED LINEAR PREDICTION 未知

    公开(公告)号：CA2181456A1

    公开(公告)日：1995-08-10

    申请号：CA2181456

    申请日：1995-02-01

    Applicant: QUALCOMM INC

    Inventor： GARDNER WILLIAM R

    IPC: G10L19/08 ,  G10L19/00 ,  G10L19/04 ,  G10L19/12 ,  H03M7/50 ,  G10L5/06 ,  G10L9/14

    Abstract: A novel and improved apparatus for encoding a signal which is bursty in nature. In a code excited linear prediction algorithm, short term redundancies are removed by formant synthesis filter (6) and long term redundancies are removed by pitch synthesis filter (4) from digitally sampled speech, and the residual signal which is bursty in nature must be encoded. The residual signal is encoded using three parameters a burst shape index corresponding to a burst shape provided by burst element (10), a burst gain which scales the burst shape through scalar multiplication in multiplier (14), and a burst location value which determines the temporal location of the scaled burst in variable delay element (16). Together the three parameters specify a waveform to match the residual signal. Further disclosed is a closed loop exhaustive search method by which to find the best match to the residual waveform and a partially open loop method wherein the burst location is determined by an open loop analysis of the residual waveform, and the burst shape and gain parameters are determined in a closed loop fashion. The matching operations are performed by minimizing the mean squared error (MSE) using summing element (18), energy computation element (20) and minimization element (22).

    Method and system for the arrangement of vocoder data for the masking of transmission channel induced errors
    55.
    发明专利
    Method and system for the arrangement of vocoder data for the masking of transmission channel induced errors 未知

    公开(公告)号：AU3593993A

    公开(公告)日：1993-09-01

    申请号：AU3593993

    申请日：1993-01-26

    Applicant: QUALCOMM INC

    Inventor： GARDNER WILLIAM R ,  JACOBS PAUL E

    IPC: G10L19/02 ,  G10L19/00 ,  G10L19/06 ,  H03M13/35 ,  H04B1/66 ,  H04L1/00 ,  G10L9/02

    Abstract: A method and system by which parameter data representative of vocoded speech are organized into a data packet for transmission so as to reduce the impact of transmission channel induced errors on the data packet. A data packet is constructed with certain most perceptually significant bits of parameter data at the beginning of the data packet. Following in the data packet are lesser perceptually significant bits of the same parameter data. Other parameter data then follows in the data packet. Interleaved in the data packet following the most perceptually significant bits at the beginning of the data packet are most perceptually significant bits of other parameter data. A parity check code is computed from the most perceptually significant bits in the data packet and also interleaved in the data packet following the most perceptually significant bits at the beginning of the data packet.

    58.
    发明专利
    未知

    公开(公告)号：FI122273B

    公开(公告)日：2011-11-15

    申请号：FI20050702

    申请日：2005-07-01

    Applicant: QUALCOMM INC

    Inventor： DEJACO ANDREW P ,  GARDNER WILLIAM R

    IPC: G10L19/02 ,  G10L19/24 ,  G10L19/00 ,  G10L19/04 ,  G10L19/14 ,  G10L21/02 ,  G10L25/78 ,  H03M7/30

    Abstract: A method of adding hangover frames to a plurality of frames encoded by a vocoder, the method comprising: detecting that a predefined number of successive frames has been encoded at a first rate; determining that a next successive frame should be encoded at a second rate that is less than the first rate; and selecting a number of successive hangover frames beginning with the next successive frame to encode at the first rate, the numbering dependent upon an estimate of a background noise level.

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