Title :
A speech processing LSI for ATM network subscriber circuits
Author :
Shoji, Yasuo ; Noguchi, Osamu ; Horiguchi, Kenji ; Tsukagoshi, Shosaku
Author_Institution :
Oki Electr. Ind. Co. Ltd., Tokyo, Japan
Abstract :
A signal-processing large-scale integration (LSI) configuration and its advantages with respect to speech communications subscriber circuits on an asynchronous transfer mode (ATM) network are described. The LSI configuration combines the silence span compression/expansion function and the cell loss compensation function into a single group of three LSI chips which are capable of processing media for both pulse code modulation (PCM) and adaptive differential PCM (ADPCM) environments. A near-end echo canceller with a single speech-processing LSI which serves to absorb delays in voice packeting, as well as to absorb the influence of cell propagation delays, is described. A performance evaluation is presented. The results indicate that good speech quality can be realized on an ATM network up to cell loss rate of about 3% for ADPCM speech, and about 8% for PCM speech
Keywords :
echo suppression; large scale integration; pulse-code modulation; speech analysis and processing; subscriber loops; time division multiplexing; voice communication; ATM network subscriber circuits; adaptive differential PCM; asynchronous transfer mode; cell loss compensation function; cell loss rate; cell propagation delays; near-end echo canceller; pulse code modulation; silence span compression/expansion function; speech communications subscriber circuits; speech processing LSI; speech quality; voice packeting; Asynchronous transfer mode; Circuits; Large scale integration; Modulation coding; Oral communication; Phase change materials; Propagation delay; Pulse compression methods; Pulse modulation; Speech processing;
Conference_Titel :
Circuits and Systems, 1990., IEEE International Symposium on
Conference_Location :
New Orleans, LA
DOI :
10.1109/ISCAS.1990.112616
