Yu Liang Lin

US Patent:

7143178, Nov 28, 2006

Filed:

Jan 16, 2001

Appl. No.:

09/761341

Inventors:

Serguei Glazko - San Diego CA, US
Baaziz Achour - San Diego CA, US
Yu Chuan Lin - Encinitas CA, US

Assignee:

Qualcomm Incorporated - San Diego CA

International Classification:

G06F 15/16

US Classification:

709231, 709232, 370468

Abstract:

A system and method for detecting discontinuous transmission (DTX) frames. The inventive method includes the steps of receiving data transmitted in a plurality of frames; classifying each of the frames; analyzing the classification of a number of successive frames of the received data and providing a metric with respect thereto; and determining, in response to the metric, if a frame is a discontinuous frame. In the illustrative embodiment, the step of classifying includes the step of error checking the frames using a cyclic redundancy check (CRC) error checking protocol. The received frames are classified as good frames (G), erasure frames (E), or discontinuous frames (D). A numerical value is assigned to each of the frames based on the classification thereof. Next, the frames are filtered to provide an output Yn=Yn−1+Xn where ‘n’ is a frame number, Yn is the filter output for a given frame n, Yn−1 is the filter output for a previous frame, and Xn is a stream of input frames. A threshold is set for the output Yn to facilitate the detection of discontinuous frames.