| 摘要 |
PROBLEM TO BE SOLVED: To enable automatic switching to RDS (=FM broadcast) broadcasting the same radio program as the radio program of DAB (=digital audio broadcast) without any feeling of physical disorder when the reception state of the DAB(digital audio broadcast) becomes worse. SOLUTION: In view of differences in the FM modulation degree of RDS among broadcasting countries of RDS, the broadcasting country of a radio program is checked with FIG0/2 of DAB and the FM modulation degree is found from the broadcasting country. When the FM modulation degree is 75 kdev, the amplitude of a demodulated signal of RDS is lowered by 5 dB and then sent to a subsequent stage. Consequently, when the sound volume of the sound source is equal, the sound is outputted from a speaker 24 with the same sound volume with an FM modulation degree of 40 Kdev even if the FM modulation degree is 75 kdev.
|
