Radio communication system operable in cooperation with a vox system.

摘要

In a radio communication system, a mobile station (11) comprises a detecting circuit (16) for producing a detection signal during presence of an audio signal. A producing circuit (31) delivers a predetermined coded data signal to the autio signal circuit (14) and supplies a duration signal to a power unit (17) at the end of the detection signal. The power unit disables the transmitting circuit during absence of the detection signal and the duration signal. The transmitting circuit transmits a transmission radio signal modulated by the audio signal and the predetermined coded data signal. A fixed station (12) comprises a separating circuit (44) for separating a reproduction of the predetermined coded data signal from a reproduction of the audio signal. A discriminating circuit 45) discriminates the reproduction of the predetermined coded data signal. Consequently, the fixed station is able to discriminate between presence and absence of the audio signal.