Patent ID: 6862464

Claim:
A communications system, comprising: a first wireless communication terminal; a second wireless communication terminal; a base station including: (a) a detector which detects failure of power to the base station, including a bipolar transistor or a field effect transistor FET connected between a power switching unit and ground and having a base or gate connected to receive direct current power, (b) the power switching unit including: a first switch switching power of the first terminal to the base station according to an output from the detector, a first diode connected in a forward direction to an output terminal of the first switch; a second diode preventing power of a charging power supply unit from being applied to a power supply unit of the base station; and a third diode preventing the power of the charging power supply unit from being applied to the first terminal except for a main processor of the first terminal, (c) a power intercepting unit, including: a second switch switching the power output from the charging power supply unit to the first terminal during normal operation, wherein if the main processor recognizes the power failure, the first switch is turned on and the second switch is turned off by the power from the charging power supply unit, and (d) a processor which manages communications between the second terminal and the base station while the base station receives power from the charging power supply unit.