CASCADED POWER SYMMETRICAL IIR FILTER BANKS AND CONTINUITY CONSTRAINED ADAPTIVE ALGORITHMS FOR ACOUSTIC ECHO CANCELLATION IN SUBBAND

The problem of aliasing in subband acoustic echo cancellation (AEC) is addressed. Filter banks with implicit notch filtering are derived fro m cascaded power symmetric-infinite impulse response (CPS-IIR) filters . It is shown that adaptive filters used with these filter banks must be coupled via continuity constraints to reduce the aliasing in the re sidual echo. A continuity constrained NLMS algorithm is therefore prop osed and evaluated.