Acoustic Echo Cancellation Employing Delayless Subband Adaptive Filters
نویسندگان
چکیده
The use of hands-free communication in cars, computer applications and video conferencing has created a demand for high-quality acoustic echo cancellation. In these applications the acoustic channel has typically a long impulse response in the order of 100ms. Typical lengths of adaptive FIRfilters can be 500-1500 taps. In order to reduce the complexity and also to improve the convergence rate, subband processing schemes have been suggested. This paper presents an implementation of a delayless subband adaptive filter. The study shows a possible suppression of about 30 dB and also a more rapid convergence compared to a fullband LMS-filter.
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