| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic frequency controller capable of quickly and surely controlling frequencies. SOLUTION: The rate of change of the angle of rotation of a quadrature demodulation signal outputted from a quadrature demodulator is calculated by an angel of rotation rate-of-change calculator 42, and whether or not the rare of change is stable is judged by a judging part 43 so that whether or not any non-modulated carrier is being received can be judged. When it is judged that the non-modulated carrier is being received, a control value converter 44 converts the angle of rotation change-or-rate into a control value, and controls the oscillation frequencies of a local oscillator. |
