PURPOSE: To make the manual setting operation of a squelch level at a base station and a mobile station unnecessary by determining the setting timing of the squelch level according to electric field level information, and setting the squelch level to meet the electric field level information at this timing.

CONSTITUTION: A squelch level setting circuit 13 sets the setting timing of the squelch level after longer time elapses in proportion as the value of the received electric field level to meet the electric field level information is smaller, and sets the squelch level to meet the electric field level information at that timing. A squelch circuit 12 interrupts a demodulated signal given from a receiver 11 according to the compared result of the electric field level information and the set squelch level.