or a judging condition or the input applies to other cases and outputs each multiplier coefficient obtained from each case a judgment logic of the i q value judging unit 41 is implemented by a logical circuit the judging condition 1 is for judgment whether the absolute value of the i signal is at least an upper limit value or the absolute value of the q signal is at least the upper limit value when the judging condition 1 is established the i q value judging unit 41 outputs a multiplier coefficient a 1 the judging condition 2 is for judgment whether the absolute value of the i signal is not more than a lower limit value and the absolute value of the q signal is not more than the lower limit value when the judging condition 2 is established the i q value judging unit 41 outputs a multiplier coefficient a 2 in other cases 1 0 is output as the multiplier coefficient the upper and lower limit values are to be set in advance by a designer and are determined by making experiments and simulations in addition the multiplier coefficients a 1 and a 2 are to be determined in advance by making experiments and simulations on condition that a relation a 1 lt 1 0 lt a 2 be satisfied that is when the judging condition 1 is established the absolute value s of one of or both of the i signal and the q signal of the phase.