outputted from the carrier phase difference comparator 15 the sir value comparator 16 directly outputs the sir value outputted from the sir estimator 12 to the sir combiner 17 in the sir combiner 17 the total of the sir values outputted from the sir value comparator 16 is calculated and outputted as the sir output 2 as described above according to the embodiment of the present invention if there exists any pair of paths satisfying the condition that the difference in path delay amount is not more than the predetermined threshold value u03c4 th and also the difference in carrier phase is not more than the predetermined threshold value u03b8 th with respect to the sir values of each path pair i u2032 j u2032 outputted from the carrier phase difference comparator 15 the sir value comparator 16 outputs only one larger sir value therefore the sir value of the same path is prevented from being added twice in this case the total number of the sir values outputted from the sir value comparator 16 is smaller than k the operation of the embodiment according to the present invention will be described the reception signal 1 is inputted to the path detector 10 and the path delay amounts u03c4 1 to u03c4 k detected are shared to the de spreaders 11 1 to 11 k and also simultaneously inputted to the path delay difference.