Microphone Diversity Combining for In-Car Applications

• Main Authors: Freudenberger Jürgen, Stenzel Sebastian, Venditti Benjamin
• Format: Article
• Language: English
• Published: SpringerOpen 2010-01-01
• Series: EURASIP Journal on Advances in Signal Processing
• Online Access: http://asp.eurasipjournals.com/content/2010/509541

<p/> <p>This paper proposes a frequency domain diversity approach for two or more microphone signals, for example, for in-car applications. The microphones should be positioned separately to insure diverse signal conditions and incoherent recording of noise. This enables a better compromise for the microphone position with respect to different speaker sizes and noise sources. This work proposes a two-stage approach. In the first stage, the microphone signals are weighted with respect to their signal-to-noise ratio and then summed similar to maximum ratio combining. The combined signal is then used as a reference for a frequency domain least-mean-squares (LMS) filter for each input signal. The output SNR is significantly improved compared to coherence-based noise reduction systems, even if one microphone is heavily corrupted by noise.</p>