| 摘要 |
PROBLEM TO BE SOLVED: To stably present a signal of a best quality to a viewer corresponding to a receiving state when a service is presented for transmission as the signals of high and low hierarchies through different plural modulation systems of a required CN in order to improve the time rate of broadcasting or the like. SOLUTION: An area is divided into plural areas for each modulation system and further for each BER and the transition procedure of areas is predetermined from each area. Corresponding to each modulation system, on the other hand, a receiving state is successively measured and collated with a table and according to the transition procedure, the device is operated so as to extract and present or output only the signal of the best quality to external output equipment. |
