PURPOSE: To reduce the energy consumption of a handset by intermittently making the handset into a receiving mode at a prescribed time interval.

CONSTITUTION: When the ring signal of an incoming call is supplied from a line wire, the transmission command of the control signal of the incoming call is supplied to an arbitrary base unit and thus, the control signal of the incoming call is continuously transmitted for 2200m seconds from the base unit. On the other hand, for plural handsets, the intermittent reception for two seconds is executed by the control of a CPU 4 with an aibitrary timing respectively, the control signal of the incoming call is received with the intermittent reception by a receiver 1 and then, thereafter, the continuous reception condition is obtained. When the completion of the control signal of the incoming call is detected in the continuous receiving condition, the control signal of the reception response from a representative handset is transmitted from a transmitter 2, further, the response signal of the switching completion of the reception channel is transmitted by respective handsets and the incoming call condition is obtained.