Low-complexity robust sparse channel identification using partial block wavelet transforms-analysis and implementation

Abstract

This paper presents a novel implementation for identifying sparse telephone network echo channels. The new scheme follows the approach used in [1] in that the location of the channel response peak is estimated in the wavelet domain. A short time-domain adaptive filter is then located about the estimated peak to identify the sparse response. The primary purpose of this paper is to present an efficient design of such system. The use of a new block wavelet transform results in both 70% less computational complexity and improved peak detection. A new robust time-domain adaptive filtering is also proposed which significantly reduces the jitter problem in [1]. Monte Carlo simulations show excellent echo cancellation for a typical ITU-T channel.