| 摘要 |
PURPOSE:To reduce the scale and size for stable operation circuit, by using two phase detectors and producing the similar signal as four phase detector outputs through the operation of the output. CONSTITUTION:Modulated input signal and the output signal of the voltage controlled oscillator 3 are compared with two phase detectors 101, 102 and the phase difference of them is detected. Further, the phase of the output signal of the oscillator 3 of one phase detector 101 is phase-shifted by pi/2 at the phase shifter 201. The outputs of the phase detectors 101, 102, and the output of the adders 501, 502 operating the outputs are in absolute value conversion and rectified to obtain four outputs, which are operated and switched to form the phase error signal in pi/4 radian period. |
