Real-time binaural noise reduction in diffuse noise field

In this paper, we present a real-time noise reduction algorithm for binaural sound devices operating in diffuse noise fields. The diffuse noise PSD is estimated in a form of the minimum eigenvalue of the (2×2) input covariance matrix. To solve the under-estimation problem at low-frequencies, a compensation scheme is used. Also, to alleviate spectral bias due to smoothing, the estimated noise PSD is scaled by a smoothing factor. The proposed algorithm was implemented in real-time using a 16-bit programmable DSP core. Real-time implementation indicates that the algorithm requires less than 4MHz clock, so that it is suitable for wearable sound devices such as binaural hearing aids and headphones with noise reduction features.