| 摘要 |
PURPOSE:To obtain the monitor circuit operated stably with a simple circuit constitution, by adding simple PSK modulation wave phase detection circuit to the monitor circuit, without using expensive measuring unit. CONSTITUTION:The monitor circuit 12 of PSK modulator is provided with the delay circuits 22-24 delaying the nonmodulation wave branched at the directional coupler 2 from the output of the local oscillator 1 of modulator, the output of the circuit 23 is fed to the phase detector 26 and the output of the circuit 24 is fed to the phase detector 25. Further, the output branched at the directional coupler 10 is branched at the distributor 21 and input to the phase detectors 25, 26 and the signals of pi/2 and 3pi/2 phase is detected at the detector 25 and the phase 0 and pi signal is at the detector 26. The output detected is divided into two at the distributors 27, 28, the output of the distributors 27, 28 is fed to the switching unit 41 for the integrated output of each phase (0, pi/2, pi, 3pi/2) via the operational amplifiers 29- 32, slicers 33-36, and integrators 37-40, the state of each phase is monitored at the instrument 42 to constitute the monitor circuit 12 simply. |
