| 摘要 |
PROBLEM TO BE SOLVED: To reduce the circuit scale by using part of band pass filters in common. SOLUTION: A FM receiver receives an FM signal on which 1st and 2nd additional information signals (radio data system RDS and data radio channel DARC signals) whose bit rate differs from each other are multiplexed. The additional information signals that are FM-detected are fed to a common band pass filter 50. The RDS signal extracted by the band pass filter is fed to a 1st decoder system 20, where the signal is decoded and the DARC signal extracted by the band pass filter is fed to a 2nd decoder system 30, where the signal is decoded. The band characteristic of the band filter is selected to extract any signal according to a selection signal from a control section 51. The band pass filter consists of a BPF 60, an HPF 54, an LPF 34 and switches SWa, SWb and only the BPF is used for the band pass filter for the RDS signal.
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