A two-stage algorithm for determining talker location from linear microphone array data

Abstract

A microphone array system for speech data input must include a robust algorithm for determining the location of the desired talker. Here, a two-stage talker location algorithm based on filtered cross-correlation is introduced. At each stage, maximization of a sum-of-independent-cross-correlations functional is used to establish talker position. Suitable accuracy is obtained at low cost by using multirate interpolation. Experimental evidence has shown that a two-stage procedure improves performance; in the first stage, closely spaced microphone pairs are used to determine the x location of the talker ( x 0 ), and more broadly spaced pairs are used in the second stage to find y 0 for a restricted range of x. Substantive results, based on real data, are presented to indicate performance. An efficient, global, non-linear optimization technique, stochastic region contraction (SRC), is briefly introduced and is shown to make this algorithm feasible in real time.