A base station FLC powered by a commercial power source includes a registration unit 122 for registering information of at least one mobile station using the base station, a battery 160 for supplying power to the base station, a power control unit 150 capable of switching a power supply for the base station from the commercial power source to the battery, and a transmission unit 110, 140 for transmitting a message to a mobile station registered at the registration unit when the power supply for the base station is switched from the commercial power source to the battery by the power control unit.