Minimum-distortion-based self-steering algorithm for microphone arrays using switched fixed beamforming

This article presents a new self-steering algorithm for microphone arrays in audio communications devices such as desktop phones, mobile handsets and multimedia tablets. The general framework is that of fixed beamforming on a predefined set of look directions to cover the spatial range of interest, followed by post filtering. The proposed algorithm improves on existing algorithms by introducing a feedback mechanism between signal-path beamforming and talker localization instead of the conventional two-step approach, with the latter implemented as an independent preprocessing step to the former. The new algorithm is shown to be an extension of the popular Steered Response Power (SRP) algorithm and is compatible with traditional decorrelation techniques such as Phase Transform (PHAT).