| 摘要 |
PURPOSE:To make the detection of a carrier phase fluctuation into a high sensitivity, to execute a low energy consumption and simultaneously, to execute a non-adjustment by providing a phasing detector and a time rate measuring device, and measuring a time rate or a frequency in which a fluctuated waveform exceeds a threshold value. CONSTITUTION:An input IF signal is multiplied with a reproducing carrier by means of a multiplier 7, simultaneously, multiplied with a wave, in which the phase of the reproducing carrier is pi/2-phase-shifted, by means of a multiplier 7a, and inputted through LPFs 8 and 8a to a multiplier 9. When the phase fluctuation is generated to the input IF signal by the change of a transmission line, the fluctuated waveform proportionate to a phase difference between the input IF signal and reproducing carrier appears to the output of the multiplier 9. The fluctuated waveform is inputted through an LPF 14 to a phasing detector 15, the output condition of the detector 15 is changed from '0' to '1' at the time of exceeding the threshold value, and a time rate measuring device 16 in a next stage measures the rate of a time when the output of the detector 15 is made into '1' condition. Thus, when the phase fluctuation is generated to the input IF signal, the value of the time rate output of the measuring device 16 is made large, the phase fluctuation of the input IF can be detected with a high sensitivity, and simultaneously, the low energy consumption and non-adjustment can be executed. |
