摘要 |
<p>A method and apparatus for transmitting common information to a plurality of user terminals within a geographic region. The method and apparatus are useful in a satellite communication system (100) having a gateway (120, 122), and a plurality of satellites (116, 118) that orbit such that they are not stationary with respect to a point on the surface of the Earth. The method includes the step of generating a list identifying a plurality of common data channels (702) over which the common information will be transmitted. The list can include, for each of said plurality of common data channels, information identifying a predetermined satellite, beam (401-416), frequency, and channel. Due to the orbiting of the satellites (116, 118), the list changes over time. The method also includes the steps of transmitting (708), from the gateway to the geographic region (502, 504, 520, 522), the common information on the plurality of common data channels. The method also includes receiving (720), at a user terminal (124, 126), the common information over at least one of the plurality of common data channels.</p> |