Title :
Effects of vocoder distortion on network echo cancellation
Author :
Huang, Y. ; Goubran, R.A.
Author_Institution :
Dept. of Syst. & Comput. Eng., Carleton Univ., Ottawa, Ont., Canada
Abstract :
In packet based telephone networks, if there are vocoders in the echo path, due to vocoder distortion, the performance of the echo canceller is degraded. The paper proposes a simulation model to study the effects of vocoder distortion on the performance of echo cancellers. The normalized least mean square (NLMS), the fast transversal filter (FTF) and the fast affine projection (FAP) algorithms are used for the echo canceller. Simulation results show that the vocoders cause significant degradation in echo return loss enhancement (ERLE), and FAP performs the best among the three algorithms
Keywords :
digital simulation; echo suppression; least mean squares methods; packet switching; telecommunication computing; telephone networks; vocoders; ERLE; FAP algorithms; FTF; NLMS; echo canceller; echo path; echo return loss enhancement; fast affine projection; fast transversal filter; network echo cancellation; normalized least mean square; packet based telephone networks; performance degradation; simulation model; vocoder distortion; Adaptive filters; Computational modeling; Convergence; Degradation; Echo cancellers; Financial advantage program; Speech; Telephony; Transversal filters; Vocoders;
Conference_Titel :
Multimedia and Expo, 2000. ICME 2000. 2000 IEEE International Conference on
Conference_Location :
New York, NY
Print_ISBN :
0-7803-6536-4
DOI :
10.1109/ICME.2000.869633
