Separation and Equalization of Cross-Coupled Signals by Adaptive Cancellation

Abstract

This paper describes an adaptive noise cancellation structure suitable for the separation and equalization of signals that coupled due to the approximate placing of primary and auxiliary transducers, with no distinction between the inputs of being both signals or signal and noise. This structure is based on cross-coupled LMS delay line cancellers for signals enhancements and two other LMS delay line equalizers that equalize the signals against channel distortions result due to placing the two observation sensors far enough (or via barriers) from the signals sources. The structure is configured with a topology that looks like the mirror image of the symmetric cross-coupling of the input signals. This structure is shown, under certain circumstances, to estimate either source signal, or both, with low distortion when the transmission paths between primary and secondary sensors have low attenuation and the primary signal is continuous. An enhanced performance would be achieved when the primary signal is intermittent and a signal energy detector is used. The main issues of the problem involved in this paper are the analysis of the structure topology, system stability and convergence of the adaptive elements transfer functions to solution(s) that ensures the signals separation and equalization by adaptive estimation algorithm.