| 摘要 |
An automatic frequency control circuit comprises an quadrature demodulation unit (10) for creating an in-phase signal and an antiphase signal by quadrature-demodulating a Gaussian Minimum Shiftkeying signal and supplying an electric field strength signal exhibiting an electric field strength of the Gaussian Minimum Shiftkeying signal as well as the created in-phase and antiphase signals; a quality judging unit (30) for judging the quality of the Gaussian Minimum Shiftkeying signal and creating an automatic frequency-controlling data indicating a compensation amount in accordance with the obtained quality signal; a converter (20) for converting into digital signals the in-phase signal, antiphase signal and electric field strength signal supplied from the quadrature demodulation unit and converting the automatic frequency-controlling data into an analog signal; a compensating circuit for compensating the frequency of the GMSK signal on the basis of the compensation amount indicated by the automatic frequency-controlling data converted into an analog signal by the converter. <IMAGE> |
