PURPOSE: To prevent a synchronizing step-out and a random selection error by selecting the output decision value of the equalizer of a branch where the average change error is minimized and then updating the tap gain coefficients of all equalizers by the recalculated equalization error.

CONSTITUTION: The high frequency signals received by the branches I and II are supplied to the equalizers 14 and 24 as the base band signals 13 and 23 through the receiver circuits 12 and 22. Meanwhile the equalization errors 15 and 25 of both equalizers 14 and 24 are supplied to the equalization error average value detector circuits 16 and 26 respectively. Then the average value of equalization errors equivalent to past N symbols including an equalization point is calculated, and the branch of smaller average equalization error is selected by an equalization error comparator 31. Based on this selection deciding value, the equalization errors of the decision feed back type equalizers 14 and 24 are recalculated by the equalization error recalculating parts 101 and 201 respectively and fed back to both equalizers 14 and 24. then the tap gain coefficients of the equalizers 14 and 24 are updated by those recalculated equalization errors. Thus the synchronizing step-out due to the integration of equalization errors can be evaded.