TDOA INFORMATION BASED VAD FOR ROBUST SPEECH RECOGNITION IN DIRECTIONAL AND DIFFUSE NOISE FIELD

Abstract

A two-microphone algorithm is proposed to improve automatic speech recognition (ASR) rates when target speech is corrupted by directional interferences and diffuse noise simultaneously. The algorithm adopts the time difference of arrival (TDOA) to suppress directional interferences and a TDOA-information based voice activity detector (VAD) to suppress diffuse noise. Simulation results show the proposed algorithm is effective in improving ASR rates in a sound field mixed with a directional interference and diffuse noise. Compared with the phase difference (PD) algorithm, the proposed method gives comparable recognition rates when facing a directional interference and much higher and more robust recognition rates when diffuse noise emerges.