A novel cost-effective multi-path adaptive interpolated FIR (IFIR)-based echo canceller

Abstract

In this paper, a multi-path adaptive interpolated FIR (AIFIR)-based echo canceller is presented to perform the echo cancellation in full-duplex digital transmission over DSL. The proposed multi-path approach inherits the concept of the AIFIR-based echo canceller, where the long tail portion is modelled by an adaptive sparse FIR filter. A multi-path structure is addressed to break the inherent design tradeoffs in the conventional AIFIR-based echo canceller. More than one adaptive IFIR filter, modelling the corresponding tail portions of echo path, are employed. Also, an efficient implementation of the Image Compress Filter (ICF) is provided to reduce the complexity in performing the function of multi-ICFs. In addition, we apply the proposed scheme to the design of an echo canceller in an SHDSL transceiver. Computer simulations show that the flexible multi-path AIFIR-based echo canceller can reduce computational complexity 20% compared with previous works. About 60% complexity saving is obtained compared with the direct transversal implementation of an echo canceller.