Satellite system using time domain beam hopping
A satellite communication system comprises one or more non-geostationary satellites. Each satellite is configured to provide a plurality of spot beams using time domain beam hopping among the spot beams. The spot beams are divided into hopping groups and each satellite is configured to switch throughput and power among spot beams in a same hopping group at intervals of an epoch over a hopping period according to a hopping plan. Each satellite is configured to receive, change and implement the hopping plan in orbit while the satellite moves in relation to a fixed geographic coverage region. The satellites are programmable to assign any combination of epochs in a hopping plan among spot beams of a same hopping group and to route throughput between spot beams.
1. A satellite communication system, comprising:
a non-geostationary satellite configured to provide a plurality of spot beams using time domain beam hopping among the spot beams, the spot beams are divided into hopping groups, the satellite is configured to switch throughput among spot beams in a same hopping group.
2. The satellite communication system of claim 1 , wherein:
at any instance in time only a subset of one or more spot beams of a same hopping group will be active while the other spot beams of the same hopping group will be inactive;
the satellite includes an antenna system, a digital channelizer and a selection matrix in communication with the digital channelizer and the antenna system;
the antenna system provides the spot beans, including uplinks and downlinks;
the digital channelizer routes spectrum between uplinks and downlinks; and
the selection matrix switches throughput among spot beams in a same hopping group for routed spectrum.
3. The satellite communication system of claim 1 , wherein:
the non-geostationary satellite includes a forward path and a return path; and
the forward path has different hopping plans than the return path.
4. The satellite communication system of claim 1 , wherein:
the spot beams are divided into zones; and
at least a subset of hopping groups comprising one spot beam per zone.
5. The satellite communication system of claim 1 , wherein:
a first plurality of spot beams are configured to illuminate a first area at Earth's Equator;
a second plurality of spot beams are configured to illuminate a second area away from Earth's Equator;
the first plurality of spot beams are divided into a first set of zones;
the second plurality of spot beams are divided into a second set of zones;
the first plurality of spot beams are divided into first hopping groups with at least a subset of the first hopping groups comprising one spot beam per zone of the first set of zones; and
the second plurality of spot beams are divided into second hopping groups with at least a subset of the second hopping groups comprising one spot beam per zone of the second set of zones.
6. The satellite communication system of claim 1 , wherein:
the plurality of spot beams are non-articulated spot beams relative to the satellite; and
the satellite further comprises steerable spot beams that do not perform beam hopping, the steerable spot beams are routable to the plurality of spot beams.
7. The satellite communication system of claim 1 , wherein:
the satellite is configured such that the hopping groups are arranged with member spot beams adjacent and consecutive in an orbital direction.
8. The satellite communication system of claim 1 , wherein:
the satellite is configured such that the hopping groups are arranged with other hopping group spot beams adjacent and consecutive in an orbital direction.
9. The satellite communication system of claim 1 , wherein:
the satellite is configured to switch throughput between spot beams at intervals of an epoch over a hopping period according to a hopping plan; and
the satellite is configured to change the hopping plan in orbit while the satellite moves.
10. The satellite communication system of claim 9 , wherein:
the non-geostationary satellite includes a payload comprising a plurality of switching components;
the plurality of spot beams transmit data in a frame that includes a payload transition time; and
the payload transition time is implemented by different groups of switching components at different times such that different groups of switching components reconfigure for a new hopping plan at different times.
11. The satellite communication system of claim 1 , wherein:
the satellite is configured to switch throughput among spot beams in a same group according to a hopping plan;
the hopping plan has a total number of epochs; and
the satellite is programmable to assign any combination of the total number of epochs among spot beams in a same hopping group.
12. The satellite communication system of claim 1 , wherein:
the satellite is configured to route throughput between spot beams in a same group according to a hopping plan;
the hopping plan has a total number of epochs; the satellite is programmable to assign any combination of the total number of epochs among spot beams in a same hopping group; and
the hopping plans between hopping groups with spot beam members adjacent to spot beams members of other hopping groups are planned to avoid inter-beam interference.
13. The satellite communication system of claim 1 , wherein:
the satellite is configured to switch throughput among spot beams at intervals of an epoch over a hopping period according to a hopping plan;
each epoch includes an active time, a late arrival window, a payload reconfigure time and an early arrival window;
during the active time of a current epoch, the satellite is configured to transmit data for the current epoch;
during the late arrival time, the satellite is configured to transmit data that arrived late for the current epoch;
during the payload reconfigure time, the satellite reconfigures selection of which beams receive throughput for a next epoch;
during the payload reconfigure time, the satellite reconfigures routing connectivity between steerable beams and non-articulated beams for a next epoch; and
during the early arrival window, the satellite is configured to transmit data that arrived early for the next epoch.
14. The satellite communication system of claim 1 , wherein:
the satellite is configured to switch throughput between spot beams at intervals of an epoch; and
the satellite is configured to receive data for a particular epoch that was sent previous to a start of the particular epoch by a time period that is greater than 20 times the length of the epoch.
15. The satellite communication system of claim 1 , wherein:
the satellite is configured to switch throughput between spot beams at intervals of an epoch; and
the satellite is configured to switch throughput at a number of epochs based on the uplink and downlink demand from user terminals in the hopping group beam members.
16. The satellite communication system of claim 1 , wherein:
the satellite is configured to switch throughput between spot beams at intervals of an epoch; and
the satellite is configured to switch throughput at a number of epochs based on the uplink and downlink demand from user terminals and gateways in the hopping group beam members.
17. The satellite communication system of claim 1 , further comprising:
additional satellites that together with the non-geostationary satellite form a constellation of non-geostationary satellites that each are configured to provide a plurality of spot beams using time domain beam hopping among the spot beams;
each satellite of the constellation has a same beam map; and
each satellite of the constellation is configured to travel along a same orbital path.
18. A satellite communication system according to claim 1 , wherein:
the non-geostationary satellite configured to provide a gateway beam to communicate with multiple gateways that use different epochs to communicate with subscriber terminals.
19. A satellite communication system according to claim 1 , wherein:
the non-geostationary satellite configured to provide steerable gateway beams;
the non-geostationary satellite includes a beam hopping plan for the plurality of spot beams using time domain beam hopping, a beam steering plan for the steerable gateway beams and a connectivity plan for on-board routing between the gateway beams and the plurality of spot beams using time domain beam hopping; and
the hopping plan and the connectivity plan are structured as a sequence of epochs.
20. The satellite communication system of claim 1 , wherein:
the non-geostationary satellite configured to provide a frequency plan for the plurality of spot beams such that the subscriber terminals and the gateways use different frequencies.
21. The satellite communication system of claim 1 , wherein:
the non-geostationary satellite configured to provide a frequency plan for the plurality of spot beams such when a particular spot beam of the plurality of spot beams serves a gateway and subscriber terminals then the subscriber terminals and the gateway use different frequencies.
22. A satellite communication system according to claim 1 , wherein:
the non-geostationary satellite configured to provide a high capacity steerable spot beam that does not implement time domain beam hopping; and
the non-geostationary satellite configured to provide a full mesh network communication for subscriber terminals communicating via the high capacity steerable spot beam.
23. A method of operating a satellite communication system, comprising:
providing a plurality of spot beams from a non-geostationary satellite as the satellite moves across a planet surface, the spot beams are divided into hopping groups; and
performing time domain beam hopping for the plurality of spot beams based on the hopping groups including switching throughput among spot beams in a same hopping group so that a subset of spot beams in each hopping group are active at any given time.
24. The method of claim 23 , wherein:
the performing time domain beam hopping includes moving throughput between spot beams in a same hopping group according to a beam hopping plan; and
the method further comprising receiving in orbit the beam hopping plan, gateway beam steering plan, high capacity beam steering plan and user beam to gateway beam connectivity instructions for each hopping group.
25. The method of claim 24 , further comprising:
receiving in orbit changes to the beam hopping plan and implementing the changes to switch throughput among spot beams in a different manner.
26. The method of claim 23 , further comprising:
dynamically routing spectrum between spot beams.
27. The method of claim 23 , further comprising:
programming the non-geostationary satellite to assign any combination of epochs in a hopping plan among spot beams of a same hopping group.
28. The method of claim 23 , wherein:
the performing time domain beam hopping includes moving throughput between spot at intervals of an epoch over a hopping period according to a hopping plan;
each epoch includes an active time, a late arrival window, a payload reconfigure time and an early arrival window;
during the active time of a current epoch, the satellite is transmitting data for the current epoch;
during the late arrival time, the satellite is transmitting data that arrived late for the current epoch;
during the payload reconfigure time, the satellite is reconfiguring selection of which beams receive throughput for a next epoch;
during the payload reconfigure time, the satellite reconfigures routing connectivity between steerable beams and non-articulated beams for a next epoch; and
during the early arrival window, the satellite is configured to transmit data that arrived early for the next epoch.