PURPOSE: To prevent the operation error from being accumulated to a tap coefficient with less amount of operation by not controlling the corrective operation of each tap but by controlling the common correction value in common all taps.
CONSTITUTION: A sample series (Xn-1) is obtained from a tap of a tap delay line 1 by applying an input signal Xn to the tap delay line 1 by applying an input signal Xn to the tap delay line 1. The mean value of the absolute values of all blocks is calculated by applying the sample value series (Xn-1) to a mean value calculation section 2. A correction value '≥h' of all taps is calculated by applying the calculated mean value to a mean correction value calculation section 3. The correction 'Δh' is given to a discrimination/control coefficient generation section 4 and when the supplied value is, e.g., larger than the threshold value, correction is applied. A multiplier 5 multiplies the control generated by using the section 4 with the all-tap mean value K1 calculated by the section 3, the result K2 is informed to a tap coefficient revision section 8 and succeedingly informed to a tap coefficient generating section 9.
UMIGAMI SHIGEYUKI
ITO ATSUHIRO
