Distributed Frequency Response Calibration Based on Consensus Strategy in Microphone Array

Frequency response mismatches among microphones inevitably result in performance deterioration of signal processing algorithms for microphone arrays. A frequency response calibration method based on the consensus strategy is proposed in this article. Adaptive calibration filters concatenated with microphone channels are first introduced to compensate for the frequency response mismatches among microphones. Then, the frequency response mismatch problem is formulated as the minimization of a cost function measuring the spectrum mismatches among neighboring microphone channel outputs. Finally, the consensus strategy is used to design the calibration filter in each microphone channel. By using the consensus strategy, the proposed frequency response calibration method is robust to the room impulse response and noise differences among microphones. The proposed method outperforms gain calibration methods and the centralized frequency response calibration method.

Automated summary

This article proposes a microphone frequency response calibration method based on the consensus strategy, using adaptive calibration filters to compensate for frequency response mismatches among microphones. By using the consensus strategy to design calibration filters in each microphone channel, the method is robust to room impulse response and noise differences among microphones, outperforming gain calibration methods and centralized frequency response calibration methods.