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    A Variable Block Size Adaptation Algorithm for Noise-Robust Acoustic Echo Cancellation
    52.
    发明专利
    A Variable Block Size Adaptation Algorithm for Noise-Robust Acoustic Echo Cancellation 未知

    公开(公告)号：CA2174342A1

    公开(公告)日：1995-05-11

    申请号：CA2174342

    申请日：1994-10-27

    Applicant: QUALCOMM INC

    Inventor： SIH GILBERT C ,  ANTONIO FRANKLIN P

    IPC: H03H21/00 ,  H04B3/23

    Abstract: An apparatus that automatically adjusts the adaptation block size for a least-mean square (LMS) adaptive filter depending on the input signal-to-noise ratio (SNR) is disclosed. The apparatus monitors the instantaneous SNR and continually adjusts the block size to provide high noise immunity, thereby increasing the convergence speed of the filter and decreasing the asymptotic mean-square error. An exemplary embodiment of the present invention is presented in the context of acoustic echo cancellation, though it is noted that the adaptive filter of the present invention is useful in any environment in which the noise characteristics are subject to change.

    MULTIPLEXED ADDRESS CONTROL IN A TDM COMMUNICATION SYSTEM
    56.
    发明专利
    MULTIPLEXED ADDRESS CONTROL IN A TDM COMMUNICATION SYSTEM 未知

    公开(公告)号：AU612253B2

    公开(公告)日：1991-07-04

    申请号：AU3349489

    申请日：1988-12-21

    Applicant: QUALCOMM INC

    Inventor： GILHOUSEN KLEIN S ,  ANTONIO FRANKLIN P ,  JACOBS IRWIN M

    IPC: H04B7/212 ,  H04J3/00 ,  H04J3/16 ,  H04J3/24 ,  H04Q7/06 ,  H04Q7/08 ,  H04Q7/12 ,  H04Q7/18 ,  H04Q7/38 ,  H04B7/26

    Abstract: A message communication system employing one or more centralized communication stations transmitting messages through Earth orbit relay satellites to mobile receivers utilizing Time Division Multiplexed (TDM) communication signals having signal time frames divided into a series of transmission channels. A predetermined number of the channels are designated as address channels with the remainder being used for data transfer. Information transmitted on the address channels is used by receivers to determine both the presence of a message and its corresponding data transmission channel. Each system receiver scans, and tracks only the communication signal address channels until a message addressed to that receiver is detected, at which time the selected receiver changes channels to the designated data channel for reception of the message. Thus, demodulation of the entire communication signal is not required and processing time and power is reduced for the typical waiting condition when messages are not being received. While a message is being received only a portion of the communication signal need to be received, demodulated and decoded. The decoded message is then displayed on a display screen or similar device for the recipient.

    METHOD AND APPARATUS FOR CONTROLLING TRANSMISSIONS OF A COMMUNICATIONS SYSTEM
    60.
    发明专利
    METHOD AND APPARATUS FOR CONTROLLING TRANSMISSIONS OF A COMMUNICATIONS SYSTEM 未知

    公开(公告)号：CA2698363C

    公开(公告)日：2014-12-02

    申请号：CA2698363

    申请日：2001-03-20

    Applicant: QUALCOMM INC

    Inventor： WALTON JAY R ,  WALLACE MARK ,  HOLTZMAN JACK ,  ANTONIO FRANKLIN P

    IPC: H04J1/05 ,  H04W72/10 ,  H04B7/005 ,  H04B7/26 ,  H04J3/00 ,  H04J11/00 ,  H04W52/18 ,  H04W52/24 ,  H04W52/26 ,  H04W52/34

    Abstract: In some aspects, each cell in the communications system can be designed to operate in accordance with a set of back-off factors that identify the reductions in peak transmit power levels for the channels associated with the back-off factors. The back-off factors are defined to provide the required power to a large percentage of the users while reducing the amount of interference. In some other aspects, the cells operate using an adaptive reuse scheme that allows the cells to efficiently allocate and reallocate the system resources to reflect changes in the system. A reuse scheme is initially defined and resources are allocated to the cells. During operation, changes in the operating conditions of the system are detected and the reuse scheme is redefined as necessary based on the detected changes. For example, the loading conditions of the cells can be detected, and the resources can be reallocated and/or the reuse scheme can be redefined. In yet other aspects, techniques are provided to efficiency schedule data transmissions and to assign channels to users. Data transmissions can be scheduled based on user priorities, some fairness criteria, system requirements, and other factors. Users are assigned to available channels based on a number of channel assignment schemes. Channel metrics are also provided, which can be used to prioritize users and for channel assignments.

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