Signal Processing for a Cocktail Party Effect
O. M. M. Mitchell, Carolyn A. Ross, G. H. Yates · The Journal of the Acoustical Society of America · 1971
A binaural listener has the ability to concentrate on speech from a particular location while suppressing speech from other locations (binaural “cocktail party” effect). In some communication situations where sounds are picked up by a microphone system for transmission on a single path to a remote listener, it would be desirable to preprocess the signals to achieve a similar effect. We describe a class of nonlinear processes for the outputs of an array of microphones which emphasize speech coming from a particular (on-center) location in a background of other sounds. These processes completely eliminate any off-center impulsive noise which is nonoverlapping at the four microphones. Results of processing outputs of real and computer-simulated microphone arrays for speech and noise signals are described. Under anechoic conditions, the processing results in reproduction of the on-center speech without change, and in distortion and attenuation of an off-center speech source. The distortion produced by the processing appears to be an important factor in subjective suppression of the off-center source.