HOWLING SUPPRESSION DEVICE, HEARING AID, HOWLING SUPPRESSION METHOD, AND INTEGRATED CIRCUIT

摘要

A howling suppression device includes a subtractor (102) which subtracts a pseudo feedback signal from an input signal; an adaptive filter (107) which produces a pseudo feedback signal for a next input signal; and a coefficient update control unit (108) which controls an update rate of a filter coefficient of the adaptive filter (107) and includes: a level calculation unit which calculates a signal level of the input signal; a signal-rising-edge detection unit which detects a rising-edge point; a reverberation section detection unit which detects a reverberation section; and an update rate control unit which sets the update rate to a first rate in the reverberation section and to a second rate in other sections . The adaptive filter updates the filter coefficient at the update rate set by the update rate control unit.