Design and application of an optimum orthogonal wavelet filter for echo cancellation

Filter banks used for subband decomposition in echo cancellation need to be perfect reconstruction filter banks, and to achieve better performance of the echo canceller, the filters need to be perfect half-band filters. A method of designing filter banks for use in echo cancellation is proposed. This method is based on linear parametrization of half-band filters. The main advantage of using this method is the orthogonality of the resultant filter banks. Experimental results based on simulated echo are given and discussed.