PURPOSE: To improve the communication quality by detecting the error rate of a signal received by plural antennas and comparing the result so as to select a reception signal minimizing a waveform distortion with respect to frequency selective fading.

CONSTITUTION: An incoming signal sent from a mobile station is received by each of receivers 521, 522 via a high frequency switch 54 from antennas 551, 552 of a base station. After a demodulated base band signal is decoded by relevant decoders 561, 562 respectively, the signal is inputted to error check circuits 111,112. The circuits 111, 112 are configured corresponding to the error check coding circuit provided to each mobile station and check the parity for each prescribed bit number to output an error bit number. The error bit numbers outputted from the circuits 111, 112 are compared by an error bit number comparator circuit 12, and the reception data signal of a reception system having a least error rate is selected via a base band switch 58 as a signal from the mobile station. Thus, a propagation line best for code transmission is employed and the communication quality is improved.