Adaptive noise suppressor.

摘要

An adaptive noise suppressor for providing noise filtered speech signals for use as adaptive line enhancers, hearing aid devices, etc. The noise suppression device employs a vector gain for the weights of the filter wherein the vector µ is selected for each frequency bin to be inversely proportional to the power spectrum. A projection operator is utilized to remove the effects of circular convolution to produce a linear convolution result wherein the weights are readjusted in a manner to minimize the difference between the input signal and the filter output signal, thereby minimizing the error signal to produce noise suppressed speech in the filtered speech output. A frequency suppression device utilizes the same principles of the vector µ and projection operator, but the filter delay is now taken to be at least greater than a phonem.