抄録
Acoustic echo signals generated by acoustic echo path have usually long duration. The echo signals are likely to be generated when meetings are held using TV-conference systems, in which loudspeakers and microphones are used. Because communication quality may become worse, these echo signals should be reduced. FIR-typed echo cancellers, however, have some problems which are increasing circuit scales and large computational burden. From these reasons, An ARMA-typed echo canceller, which is able to estimate and simulate more effectively compared with an FIR-type one, is investigated. IIR-typed adaptive digital filters have problems of stability, so we propose cascade configuration of 2nd order IIR filters, whose stability is easily checked. From extensive simulations, it is confirmed that the proposed method has good echo cancelling performance with less computational burden.
