PURPOSE: To preclude rainfall attenuation by switching 1st and 2nd transmitting means which differ in transmission quality when sent information is attenuated owing to the rainfall attenuation during information transmission between a base station and a terminal station.

CONSTITUTION: Rain or snow falls on, for example, a terminal station 3d, so the sent information is attenuated by the rainfall. The base station 1 is equipped with two transmitting means, i.e. a transmitting means which uses time-division multiplex transmission(T.D.M.) and a transmitting means which uses the time- division multiplex transmission(T.D.M.) or single-carrier single-channel transmission(S.C.P.C). Namely, which terminal station is in an attenuation state is known from chick information such as incoming call information, so switching to a transmission means of good transmission quality is performed. Consequently, information having no rainfall attenuation is transmitted between the base station 1 and terminal station 3d.