ADAPTIVE FILTER

摘要

[PROBLEMS] To provide an adaptive filter capable of sufficiently reducing a mean square error of an error signal. [MEANS FOR SOLVING PROBLEMS] An adaptive filter includes: a first transversal filter (11) for inputting an input signal; a second transversal filter (21) having the same degree as the first transversal filter and inputting the same input signal xn as the first transversal filter; and a coefficient adjustment unit (20) for calculating a filter coefficient to reduce a difference en between the output signal yn of the first transversal filter and a desired signal dn and updating filter coefficients of the first transversal filter and the second transversal filter. The output signal ypn of the second transversal filter is outputted as a filter output. By using the coefficient obtained from the first transversal filter (11), the second transversal filter (21) again performs filtering so as to reduce the error in the first transversal filter.