| 摘要 |
CM00100U This invention relates to a satellite signalling system, such as a satellite paging system, having signal coverage over a very wide area. The satellite signalling system comprises a satellite to which is coupled an antenna (88) for providing a signal beam having a variable beam area.The satellite can control the position of the antenna such that the signal beam can be directed in a predetermined sequence to a plurality of locations (28) on earth. The antenna is arranged to vary the signal beam's area in dependence on the location to which the signal beam is directed. The signal beam comprises a data signal having a data rate which can be varied by the antenna in dependence on the beam area.
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