Acoustic echo cancellation method, uses identification filters between speakers and microphones to determine necessary correction

摘要

The digital signal processing system provides adaptive control of multi-channel acoustic echo cancellation. The system uses a number of speakers and microphones, with identification filters having variable coefficients. These enable determination of the coupling between microphones and speakers, and thus cancellation of the echo which otherwise occurs. The technique provides adaptive control of multi-channel acoustic echo cancellation. The system comprises N speakers (N being an integer not less than 2) and M microphones (M being an integer not less than 1). The system further comprises NxM identification filters (Fij) with variable coefficients. The identification filter (Fij) enables estimation of the acoustic coupling between a given speaker and a given microphone, based on a pitch ( theta ) adapting the variable coefficients. The pitch ( theta ) adapting the variable coefficients is based on the presence or absence of signal in the speakers. An Independent claim is included for acoustic echo cancellation apparatus.