| 摘要 |
PURPOSE:To automatically back up a satellite channel by means of the channel itself so that the reliability of the channel can be improved by previously storing two frequencies in a base band processor and using the frequencies by switching when a fault occurs. CONSTITUTION:When a transponder TRSP repeating the output frequency becomes detective while satellite communication is normally carried on, a transponder fault notice is sent from the transponder TRSP to s satellite network control processor SNCP. The processor SNCP outputs a output frequency changing notice to a satellite access controller SAC. As a result, the controller SAC sends information to a base band processor BBP with a new output frequency thereafter. The new output frequency is one of the two frequencies stored beforehand in the E<2>PROM of the base band processor BBP and the processor BBP sets the output frequency by managing the two frequencies with a timer. |
