Polyphase allpass IIR structures for sub-band acoustic echo cancellation
نویسندگان
چکیده
The advantages and current limitations of sub-band approaches to echo cancellation are reviewed. Polyphase allpass IIR halfband decimators and interpolators are presented. Their performance is compared to QMF structures in NLMS sub-band echo cancellation for hands-free telephone signals recorded in a car. The polyphase allpass IIR case is shown to give around 2 dB more ERLE with one fifth of the number of multiplies compared to direct form QMF.
منابع مشابه
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