Delayless Subband Echo Cancellation
Blekinge Institute of Technology, Department of Signal Processing1997 (English)Conference paper (Refereed) Published
Echo suppression is a vital part of every communications system. The use of hands-free communication in cars, computer applications and video conferencing have created further demands for high-quality acoustic echo cancellation. In these applications the acoustic channel has, typically, a long impulse response in the order of 100 ms. Typical lengths of adaptive FIR-filters are 500-1500 taps, assuming a 12 kHz sampling frequency. In order to reduce the computational load and also to improve the convergence rate, sub-band processing schemes have been suggested. This paper presents a study of a delayless sub-band adaptive filter. The study shows a possible echo suppression of about 30 dB and also an improved convergence rate when compared to a fullband LMS-filter. The main issues discussed are filter bank design and a simple speech detector that gives a drastic performance improvement.
Place, publisher, year, edition, pages
Echo cancelation, Multi-rate
IdentifiersURN: urn:nbn:se:bth-10009Local ID: oai:bth.se:forskinfo56F442A0C3CF608BC1256C6A004DA123OAI: oai:DiVA.org:bth-10009DiVA: diva2:838016
Fifth International Congress on Sound and Vibration ICSV'5