Patent ID: 8180068

Claim:
A noise eliminating apparatus comprising a first microphone, a second microphone and a signal processing unit, wherein: the signal processing unit includes a linear prediction filter and a noise resynthesis filter; the linear prediction filter receives an output signal of the first microphone, predicts the output signal of the first microphone by linear prediction and generates a prediction signal; and the noise resynthesis filter is an adaptive filter which receives, as a main input signal, a first difference signal obtained by subtracting one of the output signal of the first microphone and the prediction signal from the other, receives, as an error signal, a second difference signal obtained by subtracting one of an output signal of the second microphone and an output signal of the noise resynthesis filter itself from the other, and updates a filter coefficient so that the error signal is minimized; and a clip process is performed using a predetermined threshold value in an updated term of an adaptive algorithm applied to the noise resynthesis filter, and wherein the clip process is a process in which, when a magnitude of the updated term is larger than the threshold value, the updated term is reduced so that the magnitude of the updated term becomes the threshold value, and the filter coefficient of the noise resynthesis filter is updated based on the updated term having been reduced to the threshold value.