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A packet data communication system includes a control station and a plurality of mobile terminals that communicate on demand with the control station over a wireless link. The control station has a data port for receiving data packets destined for the terminals, an arrangement for generating a plura

A packet data communication system includes a control station and a plurality of mobile terminals that communicate on demand with the control station over a wireless link. The control station has a data port for receiving data packets destined for the terminals, an arrangement for generating a plurality of data channels for carrying the data packets, and an arrangement for assigning the data packets destined for a particular terminal to one or more of the data channels. A control channel carries control information pertaining to the data channels. The channels are transmitted to the mobile terminals as an r.f. signal. The terminals have a receiver for receiving the r.f. signal, an analog-to-digital converter for digitizing the received signal, and a buffer for storing the digitized received signal. The terminals continually monitor the control channel to extract control information. The stored signal is processed to extract packet data destined for the terminal from one or more of the data channels in response to control information received on the control channel.

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A packet data communication system includes a control station and a plurality of mobile terminals that communicate on demand with the control station over a wireless link. The control station has a data port for receiving data packets destined for the terminals, an arrangement for generating a plura

A packet data communication system includes a control station and a plurality of mobile terminals that communicate on demand with the control station over a wireless link. The control station has a data port for receiving data packets destined for the terminals, an arrangement for generating a plurality of data channels for carrying the data packets, and an arrangement for assigning the data packets destined for a particular terminal to one or more of the data channels. A control channel carries control information pertaining to the data channels. The channels are transmitted to the mobile terminals as an r.f. signal. The terminals have a receiver for receiving the r.f. signal, an analog-to-digital converter for digitizing the received signal, and a buffer for storing the digitized received signal. The terminals continually monitor the control channel to extract control information. The stored signal is processed to extract packet data destined for the terminal from one or more of the data channels in response to control information received on the control channel. affic load within the capacity of the electrical power subsystem. 2. The method of claim 1 wherein the satellite comprises a battery, a solar panel that charges the battery when the solar panel is exposed to sunlight, a controller, and a memory, and wherein the assessing the capacity of the electrical power subsystem to satisfy the traffic load forecast for the satellite during the future time period comprises: determining a current state of charge in the battery; and determining a satellite ephemeris during the future time period indicating when the solar panel will be exposed to sunlight to charge the battery. 3. The method of claim 2 wherein the assessing the capacity of the electrical power subsystem to satisfy the traffic load forecast for the satellite during the future time period further comprises calculating an expected power demand during the future time period using the traffic load forecast. 4. The method of claim 3 wherein the assessing the capacity of the electrical power subsystem to satisfy the traffic load forecast for the satellite during the future time period further comprises forecasting a battery state of charge throughout the future time period using the expected power demand. 5. The method of claim 1 wherein the managing the traffic load within the capacity of the electrical power subsystem comprises: determining whether the capacity of the electrical power subsystem can satisfy the traffic load forecast; and invoking flow control on the traffic load of the satellite if the capacity of the electrical power subsystem cannot satisfy the traffic load forecast. 6. The method of claim 5 wherein the step of managing the traffic load within the capacity of the electrical power subsystem further comprises: determining whether the capacity of the electrical power subsystem can satisfy the communications traffic load forecast after flow control has been invoked; and moving subscribers of the satellite communications system to low power channels of the satellite if the capacity of the electrical power subsystem cannot satisfy the traffic load forecast after invoking the flow control. 7. The method of claim 6 wherein the managing the traffic load within the capacity of the electrical power subsystem further comprises: determining whether the capacity of the electrical power subsystem can satisfy the traffic load forecast after subscribers have been moved to low power channels; and terminating connections to subscribers if the capacity of the electrical power subsystem cannot satisfy the traffic load forecast after subscribers have been moved to low power channels.