Abstract: A dispatch system (10) uses satellites (40) to broadcast simultaneously to an individual remote unit (30), to a select group of remote units (30) or to all the remote units (30). The dispatch system (10) may assign a remote unit (30) to a unique channel if there are enough available channels, or may assign the remote units (30) to a shared channel when the number of available channels is limited. The remote units (30) are given a unique control code or a shared control code. Based on the channel and the control code, the remote unit (30) will be able to listen to the broadcast or ignore it.

Abstract: A satellite-based, world-wide cellular messaging system (5) transmits paging messages to pagers (2) via multiple beams. A pager (2) monitors multiple beams, recording the schedules for each beam, and by combining the schedules for multiple beams, ultimately determines which frames in the message groups to monitor for messages. Pager (2), which conserves battery resources by entering into a sleep mode, synchronizes quickly to its message block when it awakes.

Abstract: A satellite-based, world-wide cellular messaging system (5) transmits paging messages to pagers (2) via multiple beams. A pager (2) monitors multiple beams, recording the schedules for each beam, and by combining the schedules for multiple beams, ultimately determines which frames in the message groups to monitor for messages. As propagation characteristics degrade, an adaptive method refines the criteria for including frames into a monitoring schedule.