Energy-cognizant scheduling of store-and-forward communications with multiple priority levels in satellite systems

A satellite, comprising:

• a transceiver configured to receive a plurality of messages from a plurality of ground sources, wherein said messages are intended for a plurality of ground recipients at respective different destinations, and wherein each of the respective different destinations is associated with a contact time window during which the satellite will be in range of the ground recipients at that destination;
• a processor;
• and
• a memory having stored thereon instructions which, when executed by the processor, cause the processor to perform operations comprising:
• determining a size of each of the messages;
• estimating an amount of time needed to deliver each of the messages based on the size of each of the messages;
• determining an amount of energy that will be available from a power source for delivery of the messages during each contact window, wherein delivery of a predefined unit size of message consumes a corresponding predefined unit amount of energy;
• and
• optimizing a delivery schedule for delivering the plurality of messages to the ground recipients based on the amount of energy that will be available for delivery of the messages during each contact window and the amount of time needed to deliver each of the messages, such that a total time for delivery of the messages is minimized,
• wherein the transceiver transmits the plurality of messages according to the delivery schedule.

A device for scheduling delivery of a plurality of messages by a satellite, said messages intended for a plurality of ground recipients at respective different destinations, the device comprising:

• a processor;
• and
• a memory having stored thereon instructions which, when executed by the processor, cause the processor to perform operations comprising:
• determining, for each of said respective different destinations, an associated contact time window during which the satellite will be within range of the ground recipients at that destination;
• determining a size of each of the messages;
• estimating an amount of time needed to deliver each message based on the size of each message according to a mean busy time function;
• determining an amount of energy that will be available from a power source for delivery of the messages during each contact time window;
• and
• scheduling delivery of the plurality of messages to the ground recipients based on the amount of energy that will be available for delivery of the messages during each contact time window and the of amount of time needed to deliver each of the messages, such that a total time for delivery of the messages is minimized.