| 摘要 |
A demodulator is disclosed for effectively reducing a phase fluctuation which cannot be fully eliminated by a carrier recovery loop (feedback loop) 7. The demodulator includes subsequent feed-forward phase-compensation loop 8 which shares a phase detector with the carrier recovery loop 7. The carrier recovery loop 7 receives a digital signal after a semi-synchronous detection, detects a phase shift of the digital signal to a predefined phase position in rectangular coordinates, and compensates for the phase of the received digital signal by a first compensation value on the basis of the detected phase shift to generate an output signal. The feed-forward phase-compensation loop 8 generates an average value of the phase shift, and compensates for the phase of the output signal by a second compensation value on the basis of the averaged phase-shift value. |
