Adaptation filter device and echo canceler, update manner of filter coefficient

摘要

P To provide an adaptive filter device which controls an updating amount with a simple configuration and well follows the change of a system. PSOLUTION: The adaptive filter device calculates: a signal e' (n) where the front half of a total step number 2mSB2/SBis equal to that of an error signal e (n) and zero is obtained in remaining steps; a signal x' (n) where, in the same way and the front half of x (n) is equal to that of x (n), and zero is obtained in the steps of mSB1/SBto (2mSB2/SB-1); a correlation function between the signal e' (n) and a signal xSP*/SP' (n) of the conjugate complex number of the signal x' (n); a replace correlation function by processing an error, based ON values in the steps of mSB2/SBto (2mSB2/SB-1) of the mutual relative function; a replace cross spectrum by performing the discrete Fourier transformation of the replace correlation function; the POWER spectrum of a replace input signal; and the updating value of a filter coefficient and based ON the replace cross spectrum and the POWER spectrum. PCOPYRIGHT: (C)2007 and JPO& INPIT