DEVICE AND METHOD FOR HIGH SPEED SEARCHING ALTERNATIVE FREQUENCY OF RDS

摘要

The present invention relates to a high-speed AF processing method of the RDS, and the broadcasting signal frequencies on the AF list are arranged in frequency order and stored in a specific RAM in the RDS and PLL control unit 16, and the intermediate frequencies in the RDS and PLL control unit 16. When the level meter signal ILM is input for a predetermined level or less, the first AF broadcast signal frequency searched is lower than the currently received broadcast signal frequency when tuning to the frequency of another broadcast signal broadcasting the same program. Once the rising error signal E1 is activated, the low pass filter 11 receives the signal to control the tuner 11, and stores the AF broadcast signal frequency as a reference frequency RF in the PLL. Whenever the frequency of the broadcast signal on the list is changed, the falling error signal E2 is activated to minimize noise at a time that maximizes the noise by accelerating the tuning voltage VT adjustment time. In will allow you to realize the tuning.