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Summary: EMBEDDED JOINT SOURCE-CHANNEL CODING OF
SPEECH USING SYMBOL PUNCTURING OF TRELLIS CODES
Alexis Bernard, Xueting Liu, Richard Wesel and Abeer Alwan
Electrical Engineering Department, University of California, Los Angeles
Box 951594, 405 Hilgard Avenue,
Los Angeles, CA 90095-1594
ABSTRACT
This paper presents an embedded joint source-channel coding
scheme of speech. The source coder is an embedded variable bit
rate perceptually based sub-band coder producing bits with
different error sensitivities. The channel encoder is a Rate
Compatible Punctured Trellis code (RCPT) which permits rate
variability and unequal error protection by puncturing symbols.
Furthermore, RCPT code design naturally incorporates large
constellations, allowing high information rate per symbol. The
embedded speech coder and the rate compatible puncturing of
symbols provide the embeddibility of the joint coding scheme.
The coder is robust to acoustic noise and produces good quality
speech for a wide range of channel conditions (AWGN or
fading), allowing digital transmission of speech with analog-like
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