| 摘要 |
For use in a satellite communication system which carries out communication through a satellite by the use of an up-link frequency band and a down-link frequency band, each of the up-link and the down-link frequency bands has a plurality of frequency subbands spaced apart from one another with frequency gaps interposed between the frequency subbands. An earth station comprises a modulating arrangement (47) for modulating a selected one of the frequency subbands of the up-link frequency band by a first input signal into a subband transmission signal, a first transmitting arrangement (51) coupled to the modulating arrangement for transmitting the subband transmission signal through the selected one of the frequency subbands, a spread spectrum processing arrangement (50) for processing a second input signal into a spread spectrum transmission signal in the up-link frequency band, and a second transmitting arrangement (51) coupled to the spread spectrum processing arrangement for transmitting the spread spectrum transmission signal through the up-link frequency band. |
