| 摘要 |
<p>PURPOSE:To regenerate monitor information on a repeater easily at a regeneration side through a general FM modulator, by sending out the monitor information in the form of an FM-modulated wave obtained by imposing FM modulation on a PSK-modulated wave. CONSTITUTION:Through a frequency mixer 2 and a receiving local oscillator 3, a high-frequency PSK-modulated wave is converted into an intermediate frequency signal, which is amplified by an intermediate frequency amplifier 4 and further converted into a high-frequency signal through a frequency mixer 12 and a transmitting voltage-controlled local oscillator 20. The monitor information from a monitor control circuit 21 is supplied to the modulation input of said oscillator 20 as well and slight FM modulation is imposed on an oscillation wave, so the output oscillation wave is a PSK-FM composite modulated wave. It is amplified by a high frequency amplifier 14 and sent to a transmission switch 17 and at the same time, it is detected by a transmitting power detector 15, which when detecting a fault, sends out a warning signal to the monitor controlling circuit 21.</p> |
