摘要 |
A control unit gives acoustic environment instruction data to a picked up sound directionality control unit and an adaptive filter. According to this, the picked up sound directionality control unit generates a picked up sound signal constituted by a predetermined picked up sound directionality. The adaptive filter detects the picked up sound directionality from the acoustic environment instruction data, and reads out the filter parameter corresponding to this picked up sound directionality, from a memory. The adaptive filter sets a delay coefficient and a filter coefficient of an FIR filter, and generates a pseudo echo signal by an impulse response with respect to the received sound signal. Based on an error signal obtained by subtracting the pseudo echo signal from the picked up sound signal by an adder, the adaptive filter sets a more optimum filter parameter, and generates the next pseudo echo signal.
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