Microphone array beamforming based on maximization of the front-to-back ratio

Area of Science:

• Acoustic Signal Processing
• Array Signal Processing

Background:

• Microphone arrays are crucial for high-fidelity audio acquisition in noisy environments.
• Interference and reverberation often originate from specific regions, necessitating targeted suppression.

Purpose of the Study:

• To develop advanced beamformers for microphone arrays that preserve desired signals while minimizing interference from specific regions.
• To address limitations of traditional supercardioid beamformers, such as white noise amplification and limited directivity.

Main Methods:

• Re-examination of the front-to-back ratio and supercardioid beamformer.
• Deduction of reduced-rank beamformers using joint diagonalization.
• Extension of the front-to-back ratio definition and development of generalized and regularized beamformers.

Main Results:

• Proposed reduced-rank beamformers offer tunable compromises between front-to-back ratio, white noise amplification, and directivity.
• Generalized and regularized beamformers demonstrate improved performance in simulations.
• The developed techniques effectively minimize power from interference-dominated regions.

Conclusions:

• The novel beamformers provide enhanced control over signal processing in complex acoustic environments.
• These methods offer significant advantages for applications requiring robust audio capture amidst interference and reverberation.