In a wireless communication system having a base station and a terminal, it is important to extend the operating life of the terminal in the case of using a battery as the power supply of the terminal. Particularly in the case where a state in which a base station is not present in the range within which the terminal can communicate lasts long, the reduction of the electric power consumption during the standby of the terminal becomes an issue. The terminal monitors the received signal power strength of a signal transmitted by the base station. When the power strength exceeds a prescribed value, it is considered that the base station is present and the base station performs operations for carrying out communication with the base station.