| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem that a reception-side cannot be restored for five seconds or longer if a digital broadcast TS signal is cut even for a moment when the signal is switched from one system to the other in a present system and a standby system in the operation of a ground wave digital broadcast in Japan. <P>SOLUTION: Encoders 2a, 2b, 3a and 3b output TS signals with clearance so that TS packets of video and sound are not outputted in a fixed and unique period from GOP timing. An ISDB-T frame switching device 6 selects, switches and outputs the other broadcast TS signal from the broadcast TS signal which is outptuted till then in the broadcast TS signals of one system and two systems, which are outputted from ISDB-T frame multiplexing devices 4a and 4b. Switching timing is set to be the fixed and unique period from GOP timing. Thus, a plurality of broadcast TS signals can be switched without breaking down an ISDB-T frame structure, without disturbing video sound and with low delay. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
