| 摘要 |
PROBLEM TO BE SOLVED: To attain download surely by a reception terminal, while relieving a processing load with respect to the download of an operating program. SOLUTION: A control signal used to download an operating program to a reception terminal equipment is made up of a control signal CL1 that instructs presence of down-load to each reception terminal equipment and a control signal CL2 to start reception of download data. The control signal CL1 from a generator 1 is given to multiplexers 9-11, where the signal is multiplexed with a video signal and modulated by QAM modulation circuits 12-14, and the modulated signal is given to a multiplexer 16, where the frequency is multiplexed on the signal. Thus, the control signal CL1 is included to each channel of the video signal. The control signal CL2 from the generator 8 is modulated by a QAM modulation circuit 15, and frequency-multiplexed through a separate channel by the video signal by the multiplexer 16. When the reception terminal equipment selects a desired video channel, the presence of download data is discriminated by the control signal CL1 and receives the control signal CL2 to the download data. |
