Mobile communication base station and portable telephone terminal unit and portable communication system

摘要

PROBLEM TO BE SOLVED: To improve safety by allowing a base station to scan a stored common control channel and sending an on/off signal to an object portable telephone terminal so as to fix a reception channel thereby surely turning off a transmitter. SOLUTION: Upon the receipt of a channel fixing/release control signal from a mobile communication base station 40, a terminal equipment control section 21 fixes a reception channel. Upon the receipt of a transmitter off/on signal, the section 21 sets itself to a non transmission channel fixing waiting mode/reception channel fixing wait mode. A frequency synthesizer 18 fixes an oscillation frequency upon the receipt of a fixing signal from the terminal equipment control section 21. On the other hand, a base station control section 47 of a base station 40 scans a common control channel stored in a memory 48 to establish a communication channel with an object portable telephone terminal. Furthermore, the control section 47 sends a channel fixing/release control signal to control an on/off signal of the transmitter. Thus, the transmitter is surely turned off without a notice by the user and power is interrupted and the safety is improved.