| 摘要 |
PROBLEM TO BE SOLVED: To provide an FM receiver capable of preventing distortion due to overmodulation and deterioration in the S/N. SOLUTION: When an amplitude of an output signal of an FM demodulation circuit 18 is excessive due to the occurrence of overmodulation, an overmodulation component detection circuit 30 extracts the excessive part of the amplitude. An adder 32 adds the extracted component to a control voltage of a VCO 20. When an output voltage of the overmodulation component detection circuit 30 is added to the control voltage applied to the VCO 20, the frequency of the output signal of the VCO 20 is changed by the added voltage. As a result, the frequency shift corresponding to the overmodulation part in an intermediate frequency received by the FM demodulation circuit 18 is suppressed, and the FM modulation circuit 18 can provide an output of a signal wherein the excessive amplitude due to the overmodulation is enhanced. COPYRIGHT: (C)2004,JPO&NCIPI
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