ADAPTIVE NOISE REDUCING DEVICE

摘要

PURPOSE:To properly reduce an object voice even when the voice is a nonstationary signal like a human voice and chromatic. CONSTITUTION:This noise reducing device is equipped with a linear coupler constituted by connecting plural delay circuits having unit delay times in series and a coefficient multiplier which multiplies signals from respective taps for the linear coupler by weighting coefficients and further provided with an adaptive filter means 24 which generates a signal approximating to a reduction object signal in a principal input voice signal from a reference input voice signal. A synthesizing means 14 subtracts the output signal of this adaptive filter means 24 from the principal input voice signal. The adaptive filter means 24 is so adjusted that the output power of the synthesizing means 14 is minimized. The weighting coefficient of the adaptive filter means 24 for the tap of the linear coupler corresponding to the delay time difference between the reduction object signal in the principal input voice signal and the reduction object signal in the reference input voice signal is made relatively larger than the weighting coefficient of other taps.