A robust adaptive microphone array with improved spatial selectivity and its evaluation in a real environment

Abstract

This paper presents a new robust adaptive microphone array (AMA) and its evaluation in an echoic environment. The proposed AMA is a generalized sidelobe canceller equipped with a variable blocking matrix using coefficient-constrained adaptive filters, and a multiple-input canceller using norm-constrained adaptive filters (NCAFs). Because the NCAFs have selective nonlinearity in the relationship between coefficient norm and coefficient error, the proposed AMA has better spatial selectivity than the conventional AMA. Evaluation with real acoustic data captured in a room of 0.3-second reverberation time shows that the noise is suppressed by 19 dB. In subjective evaluation, the proposed AMA obtains 3.8 on a 5-point mean opinion score scale.