A Practical Method of Obtaining Constant Convergence-Rates in LMS Adaptive Arrays

This paper shows a practical method of eliminating the old problem of widely-disparate modal convergence rates in LMS (Least-Mean-Squares) adaptive arrays. The method is mathematically based on the Newton-Raphson iteration technique of finding zeros of a function. The practical realization is based on an extension of Compton\´s improved-feedback adaptive loop. It is shown how this modificationt results in constant and equal modal convergence rates in an adaptive array. The improved algorithm is also compared to Compton\´s original improved-feedback loop and to a "standard" LMS adaptive array. Preliminary experimental results are also shown to substantiate some of the analysis.