A robust step size adaptation scheme for LMS adaptive filters

It is shown that the known gradient step size adaptation algorithm for adaptive filters has a limited application area: it is disabled when the conditions of an independence of input signal samples are violated. The reason of this statement is the nonequivalence of the mean square error (MSE) and output error minimization relatively to the step size for correlated input samples. A robust algorithm for an adaptive step size is proposed. Its efficiency is demonstrated by simulations.

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