| 摘要 |
PURPOSE:To increase the reliability of monitor, by performing the modulation of test oscillator with in-hand signal, taking the signal of mobile station for the incoming display, and performing test with the test oscillator under non-reception condition, in the monitor system used for the base station in mobile communication. CONSTITUTION:In the monitor of receivers of squelch system in which the signal fA from the mobile station including in-band signal fTT and out-of-band signal fSU is received in the base providing a plurality of a single receiver 4 and the switching means 8 which delivers the signal fTT when the signal fSU is present after the demodulation of signal fA is provided, when the signal fA is desired to be received, the test oscillator 5 is modulated with the same signal as the signal fTT and the signal FA' is added to the receiver 4 via the directional coupler 3. Further, the test of the receiver 4 is made with the oscillator 5 and the oscillation of the oscillator 5 is stopped with the control secion 1 connected to the switching means 8 when the signal FA is in reception and test is made with the oscillator 2. |
