Satellite system having terminals in hopping beams communicating with more than one gateway

• US 10,347,987 B2
• Filed: 06/03/2016
• Issued: 07/09/2019
• Est. Priority Date: 03/29/2016
• Status: Active Grant

• Current Assignee: Maxar Space LLC (Galileo Parent, Inc.)
• Original Assignee: Space Systems/Loral Incorporated (Loral Space and Communications Incorporated)
• Inventors: Hreha, William, Wharton, Anne Elizabeth, Foulke, David Linford
• Primary Examiner(s): Wong, Xavier Szewai
• Application Number:
  US15/173,038
• Publication Number:
  US 20180006370A1
• Time in Patent Office: 1,131 Days
• CPC Class Codes: H01Q 3/2682 Time delay steered arrays
• CPC Class Codes: H04B 7/043 using best eigenmode, e.g. beam forming or beam steering
• CPC Class Codes: H04B 7/1851 Systems using a satellite or space-based relay H04B7/18508, H04B7/18521 take precedence; providing specific services H04B7/18523 - H04B7/18576
• CPC Class Codes: H04B 7/18534 for enhancing link reliablility, e.g. satellites diversity
• CPC Class Codes: H04B 7/18547 for geolocalisation of a station position fixing by direction or distance determination G01S5/00
• CPC Class Codes: H04B 7/18595 Arrangements for adapting broadband applications to satellite systems
• CPC Class Codes: H04B 7/19 Earth-synchronous stations
• CPC Class Codes: H04J 1/05 using digital techniques
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others

Abstract

A satellite communication system includes a satellite configured to provide a first plurality of spot beams adapted for communication with subscriber terminals using time domain beam hopping and a second plurality of spot beams adapted for communication with gateways. The satellite includes a spectrum routing network that is configured to time multiplex spot beams of the second plurality of spot beams with spot beams of the first plurality of spot beams so that a spot beam that is implementing beam hopping for communication to subscriber terminals communicates with different feeder beams (and, therefore, different gateways) at different times during a hopping period.

Claims

1. A satellite communication system, comprising:

a satellite configured to provide a first plurality of spot beams adapted for communication with subscriber terminals using time domain beam hopping, the satellite configured to provide a second plurality of spot beams adapted for communication with gateways, the time domain beam hopping including breaking up a set of consecutive messages received from a gateway into plural subsets of the messages, a first of the subsets being transmitted by way of one of the first plurality of the spot beams and a second of the subsets being transmitted by way of another of the first plurality of the spot beams, the satellite includes a spectrum routing network that is configured to time multiplex communications of spot beams of the second plurality of spot beams into spot beams of the first plurality of spot beams.

2. The satellite communication system of claim 1, wherein:

said time domain beam hopping is specified to occur in accordance with a currently selected one of a plurality of pre-specified time domain beam hopping plans; and

the spectrum routing network includes a digital channelizer that is programmable so as to time multiplex the communications of the spot beams of the second plurality of spot beams in accordance with the currently specified one of the plurality of pre-specified time domain beam hopping plans.

3. The satellite communication system of claim 1, wherein:

the spectrum routing network includes a digital channelizer;

the first plurality of spot beams are divided into mutually exclusive hopping groups, each hopping group consisting of a respective set of plural ones of the first plurality of spot beams wherein not all the respective plural spot beams of each hopping group are simultaneously used;

the satellite further includes an antenna system and a selection matrix in communication with the digital channelizer and the antenna system;

the antenna system provides the first plurality of spot beams and the second plurality of spot beams;

the digital channelizer routes communication signals between the first plurality of spot beams and the second plurality of spot beams; and

the selection matrix switches communication throughput among spot beams in a same hopping group such that not all the respective plural spot beams of that same hopping group are simultaneously used.

4. The satellite communication system of claim 1, wherein:

said time domain beam hopping is specified to occur in accordance with a time domain beam hopping plan having plural hopping periods with each hopping period having respective epochs;

the satellite is configured to switch communications throughput among spot beams output by the satellite at intervals of respective epochs of each of its hopping periods according to a specified time domain beam hopping plan; and

the spectrum routing network is configured to time multiplex the communications of spot beams of the second plurality of spot beams into spot beams of the first plurality of spot beams during a respective hopping period such that a particular beam of the first plurality of beams receives communication bandwidth at multiple epochs during the hopping period, the satellite is configured to route communication between different beams of the second plurality of beams and the particular beam at different epochs of multiple epochs during the hopping period.

5. The satellite communication system of claim 4, wherein:

the satellite is configured to route communication between different beams of the second plurality of beams and the particular beam at different epochs of multiple epochs during the hopping period while the particular beam remains over a particular subscriber terminal location.

6. The satellite communication system of claim 1, wherein:

said time domain beam hopping is specified to occur in accordance with a time domain beam hopping plan having plural hopping periods with each hopping period having respective epochs;

the spectrum routing network is configured to time multiplex the communications of spot beams of the second plurality of spot beams into spot beams of the first plurality of spot beams by providing communication between a particular spot beam of the first plurality of spot beams and a first spot beam of the second plurality of spot beams during a first set of epochs while the particular spot beam is over a location on a planet surface and providing communication between the particular spot beam and a second spot beam of the second plurality of spot beams during a second set of one or more epochs while the particular spot beam remains over the location on the planet surface.

7. The satellite communication system of claim 6, wherein:

the second set of one or more epochs are interleaved with the first set of epochs.

8. The satellite communication system of claim 1, wherein:

the spectrum routing network is configured to time multiplex the communications of spot beams of the second plurality of spot beams into spot beams of the first plurality of spot beams while a particular spot beam of the first set of spot beams remains over a particular location, wherein the particular spot beam of the first set of spot beams is one that constantly moves relative to the planet surface.

9. The satellite communication system of claim 1, wherein:

said time domain beam hopping is specified to occur in accordance with a time domain beam hopping plan having plural hopping periods with each hopping period having respective epochs;

the satellite is configured to switch communications throughput among spot beams output by the satellite at intervals of respective epochs of each of its hopping periods according to a specified time domain beam hopping plan;

the satellite is configured to change configuration of the spectrum routing network during implementation of given time domain beam hopping plan and while in orbit as the satellite moves in relation to a coverage area; and

the satellite is configured to change in orbit how the communications of spot beams of the second plurality of spot beams are time multiplexed into spot beams of the first plurality of spot beams.

10. The satellite communication system of claim 1, wherein:

said time domain beam hopping is specified to occur in accordance with a time domain beam hopping plan having plural hopping periods with each hopping period having respective epochs;

the satellite is configured to switch throughput among spot beams at intervals of an epoch over a hopping period according to a currently specified 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 is configured to change routing paths in the spectrum routing network for a next epoch; and

during the early arrival window, the satellite is configured to transmit data that arrived early for the next epoch.

11. The satellite communication system of claim 1, wherein:

the satellite is a non-geostationary satellite.

12. The satellite communication system of claim 1, further comprising:

additional satellites that together with the satellite form a constellation of non-geostationary satellites that each are configured to provide a separate first plurality of spot beams adapted for communication with subscriber terminals using time domain beam hopping and provide a separate second plurality of spot beams adapted for communication with gateways, the satellites each include a respective spectrum routing network that is configured to time multiplex communications of spot beams of the respective second plurality of spot beams into spot beams of the respective first plurality of spot beams.

13. A satellite communication system according to claim 12, wherein:

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.

14. A method of operating a satellite communication system, comprising:

providing a first plurality of spot beams from a non-geostationary satellite in order to communicate with subscriber terminals as the satellite moves relative to and over a planet surface;

providing a second plurality of spot beams from the non-geostationary satellite in order to communicate with gateways as the satellite moves relative to and over the planet surface;

communicating with the subscriber terminals by use of time domain beam hopping in which a set of consecutive messages received from one of the gateways is broken up into plural subsets of the messages, a first of the subsets being transmitted by way of one of the first plurality of the spot beams and a second of the subsets being transmitted by way of another of the first plurality of the spot beams;

providing signal communication between a particular spot beam of the first plurality of spot beams and a first spot beam of the second plurality of spot beams during a first set of epochs while the particular spot beam is over a location on the planet surface; and

providing signal communication between the particular spot beam and a second spot beam of the second plurality of spot beams during a second set of one or more epochs while the particular spot beam covers the location on the planet surface.

15. The method of claim 14, wherein:

the first set of epochs is interleaved with the second set of one or more epochs.

16. The method of claim 14, wherein:

the communicating by use of time domain beam hopping for the first plurality of spot beams includes moving communication throughput between spot beams of the first plurality of spot beams at intervals of an epoch over a hopping period according to a hopping plan; and

the method further comprising changing configuration of the non-geostationary satellite between providing communication between the particular spot beam and the first spot beam and providing communication between the particular spot beam and the second spot beam during the hopping plan in orbit while the satellite moves in relation to the planet surface.

17. The method of claim 14, wherein:

the communicating by use of time domain beam hopping for the first plurality of spot beams includes moving communication throughput between spot beams of the first plurality of 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 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 configuring its routing paths for a next epoch; and

during the early arrival window, the satellite is transmitting data that arrived early for the next epoch.

18. The method of claim 14, wherein:

the providing a first plurality of spot beams, communicating by use of time domain beam hopping for the first plurality of spot beams, providing a second plurality of spot beams, providing communication between a particular spot beam of the first plurality of spot beams and a first spot beam and providing communication between the particular spot beam and a second spot beam are performed separately and concurrently by multiple satellites using a same beams projecting map and traveling along a same orbital path.

19. A satellite communication system, comprising:

a non-geostationary satellite configured to provide a first plurality of beams adapted for communication with subscriber terminals and a second plurality of beams adapted for communication with gateways, the satellite is configured to perform time domain beam hopping for communications of the first plurality of beams over a hopping period of a specified time domain beam hopping plan, the time domain beam hopping including breaking up a set of consecutive messages received from one of the gateways into plural subsets of the messages, a first of the subsets being transmitted by way of one of the first plurality of the spot beams and a second of the subsets being transmitted by way of another of the first plurality of the spot beams, the specified time domain beam hopping plan being such that a particular beam of the first plurality of beams receives communication bandwidth at multiple epochs during the hopping period, the satellite is configured to further route communications through different beams of the second plurality of beams as part of communicating by way of the particular beam at different epochs of multiple epochs during the hopping period.

20. The satellite communication system of claim 19, wherein:

the satellite is configured to perform said routing of communications through different beams of the second plurality of beams while the particular beam of the first set of spot beams covers a particular location;

the first plurality of beams are spot beams divided into hopping groups;

the satellite further 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 first plurality of spot beams;

the digital channelizer routes communications between the first plurality of spot beams and the second plurality of spot beams; and

the selection matrix switches throughput among spot beams in a same hopping group.