Patent ID: 8254589
Filing Date: 2012-08-28
Classification: G10K

Abstract:
1. An active noise suppressor having a fundamental sound source which generates a fundamental waveform having a predetermined frequency, and suppresses a frequency component of noise which corresponds to the predetermined frequency by generating a control sound from a signal obtained by multiplying the fundamental waveform by an adaptive filter coefficient, comprising: a phase detecting unit that detects a phase of a current control sound and a phase of a previous control sound respectively based on a current adaptive filter coefficient and a previous adaptive filter coefficient; a change amount detecting unit that detects an amount of a phase change between the phase of the current control sound and the phase of the previous control sound; and a frequency adjusting unit that increases or decreases, by a predetermined amount, the frequency of the fundamental waveform output from said fundamental sound source, if the amount of the phase change of the control sound is larger than a predetermined threshold value.