To suppress degradation of adaptation speed by reducing a calculation amount of a coefficient update of an adaptive filter, by performing suitable tap coefficient update in a dynamically changing device and environment.

A coefficient update means 40 updates a filter coefficient of the adaptive filter by using a noise suppression signal. A peak tap position deriving means 90 derives a peak tap position for indicating the tap, when the filter coefficient becomes a peak value, by relative position relation of a noise source, with a reference input terminal 2 and a speech input terminal 1. A section classification means 41 classifies a section of a tap position corresponding to the filter coefficient by utilizing the peak tap position. A coefficient update means 40 controls an update frequency of the filter coefficient corresponding to the section, for each section classified by the section classification means 41.

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