A new auditory based microphone array and objective evaluation using e-RASTI

Two are the goals of the work presented in this paper. The first one is the implementation of a new method of speech enhancement using microphone arrays. This method gets noise reduction of speech signal using the masking properties of the human auditory system. The second goal of the paper is to use RASTI index (RApid Speech Transmission Index) for objective evaluation of speech signal quality through E-RASTI evaluation. What is new is that E-RASTI is applied to speech signals and no to RASTI-like signals. The E-RASTI index is specially suited to test reverberant speech and has been used here to evaluate the reverberation reduction produced by a microphone array based on all-pass and minimum-phase decomposition or multichannel liftering. Noise reduction evaluation has been performed with the E-RASTI index and also with more traditional methods, based on Signal to Noise Ratios (SNR). Results have demonstrated the good performance of the noise suppressor and the E-RASTI objective quality evaluator.