Estimation of a talker and listener’s positions in a car using binaural signals

Abstract

The problem of estimating the location of a sound source is described which is based on signals observed at the entrances of the two ears. The purpose is to specify the talker’s and listener’s positions within a car using the binaural signal. The talker and the listener sit in two of the four car seats. In this experiment, two kinds of head and torso simulators are used as a talker and a listener. Given information includes the acoustic transfer functions for all positional patterns. Eight patterns of acoustic transfer functions are measured, involving those that have the same positional pattern, but in which the talker faces a different direction. A Gaussian mixture model for each positional pattern is generated. The parameters we used are interaural information such as the envelope of an interaural level difference. The models are evaluated by specifying the positional pattern. Results show that we can specify positions with up to 97% (35/36) accuracy using the binaural signals of two men. Then the input signal was expanded to one with background noise that resembles a real situation, and a model that involves motion of the talker’s head was also considered.