Bit-rate reduction strategies for noise suppression with a remote wireless microphone

In single-channel non-stationary noise reduction it is paramount that a good noise reference is available in a timely manner to maintain a high quality speech signal. Using a remote wireless microphone placed close to a noise source, a good estimate of the noise power spectral density (PSD) can be acquired. This estimate, however, needs to be transmitted to the primary microphone for noise reduction. As wireless transmission is power intensive, it is desirable to reduce the bit-rate while maintaining good performance. In this paper, we propose techniques such as quantizing, frequency bin clubbing and intermittent PSD transmission to reduce the transmission bit-rate, and investigate their impact on performance.