COMPARISON OF BEAMFORMING ALGORITHMS FOR MICROPHONE ARRAYS IN MATLAB

Abstract

Subject of Research. The paper considers the main quantitative characteristics of microphone arrays in their performance analysis and beamforming algorithms applied for their study. Methods. The principal characteristics, calculation approaches and evaluations were examined. The most widespread beamforming algorithms were analyzed, such as: Delay-and-Sum (DAS), minimum variance distortionless response (MVDR), Frost’s algorithm or linearly constrained minimum variance (LCMV), generalized sidelobe canceller (GSC). The calculations and comparative analysis of the algorithms were performed in Matlab simulation environment. The following quantitative characteristics were obtained: signal-to-noise ratio, signal-interference-noise ratio, directivity index, directivity characteristics, and beamwidth. Main Results. Algorithm comparison results are presented on the example of a linear microphone array. The linearly constrained minimum variance algorithm has shown the most satisfactory results. The simulation results must be clarified by real experiments. Practical Relevance. The results of the work can be used for analysis of more complex microphone arrays and acoustic structures, such as microphone arrays with “floating” geometry and distributed microphone arrays.

Keywords

• microphone array
• beamforming
• directivity pattern
• directivity index
• frequency response