To provide an adaptive filter which has a high converging speed of a tap coefficient by updating the sum total of power value of the tap coefficient so as to decrease the number of tap coefficients which are updated in sequence from the blocks having larger sum totals of the said power value to the blocks having smaller sum totals.
A reference signal x(n) is inputted to a convolution device 2a of an adaptive filter 1. A convolutional operation is performed between a tap coefficient w1(n) of a 1st block and the signal x(n), and this arithmetic result y1 (n) is outputted to an adder 4. A reference signal x(n-N1) to which a prescribed delay time is taken into consideration is outputted to a convolution device 2b and a coefficient updating device 3b. The adder 4 adds together the arithmetic results inputted from the convolution devices 2b and 2c and outputs this addition result y(n) to a subtracter 5. The subtracter 5 subtracts the received result y(n) from an answer signal d(n) obtained from the signal x(n) that is transmitted via an unknovrn system 6 and obtains an error signal e(n). The filter 1 repeats these operations to identify the system 6.
TERAI KENICHI
KAKUBARI ISAO
