Combined Satellite and Terrestrial Communication System for Terminals Located on a Vehicle Such as an Aircraft Using a Common Set of Frequencies

• US 20180048380A1
• Filed: 03/05/2015
• Published: 02/15/2018
• Est. Priority Date: 03/05/2014
• Status: Active Grant

• Current Assignee: Inmarsat Global Limited (Inmarsat PLC)
• Original Assignee: Inmarsat Global Limited (Inmarsat PLC)
• Inventors: Khan, Ammar Hussain, Franchi, Antonio
• Granted Patent: US 10,355,772 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/18508 with satellite system used as relay, i.e. aeronautical mobile satellite service
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18539 Arrangements for managing radio, resources, i.e. for establishing or releasing a connection

Abstract

A combined satellite and terrestrial communication system may include at least one satellite earth station, for communication via a satellite with a plurality of terminals using one or more satellite links; a plurality of terrestrial stations, for communication with the plurality of terminals using one or more terrestrial links; wherein the satellite links overlap or coincide in frequency with the terrestrial links; and each of the terminals includes means for inhibiting interference between the satellite links and the terrestrial links.

Claims

1. A combined satellite and terrestrial communication system, comprising:

at least one satellite earth station, for communication via a satellite with a plurality of terminals using one or more satellite links; and

a plurality of terrestrial stations, for communication with the plurality of terminals using one or more terrestrial links;

wherein at least some frequencies used in the satellite links coincide with, and may be used simultaneously with, frequencies of the terrestrial links;

wherein the terminals are each provided in or on a respective vehicle having at least one satellite antenna, for communication with the satellite, and at least one terrestrial antenna, for communication with the terrestrial stations, such that interference is attenuated between the satellite and terrestrial antennas.

2. The system of claim 1, wherein the vehicle provides interference isolation between the satellite antenna and the terrestrial antenna.

3. The system of claim 1, wherein the vehicle is an aircraft, the satellite antenna is positioned on an upper side of a fuselage of the aircraft and the terrestrial antenna is positioned on a lower side of the fuselage.

4. The system of claim 1, wherein the one or more beams generated by the terrestrial antenna are directed towards, below, or with reference to, a horizon.

5. The system of claim 4, wherein the vehicle includes a horizon detector and a beam controller responsive to the horizon detector so as to direct the one or more beams generated by the terrestrial antenna.

6. The system of claim 4, wherein the one or more beams generated by the terrestrial antenna are directed towards one or more ground stations.

7. The system of claim 1, wherein the one or more beams generated by the satellite antenna are directed above, or with reference to, a horizon.

8. The system of claim 1, wherein the terrestrial antenna generates one or more beams directed so as to inhibit interference to or from the satellite.

9. The system of claim 1, wherein the satellite links include a satellite uplink, for transmissions from the terminals to the satellite, and the terrestrial links include a terrestrial uplink, for transmissions from the terminals to the terrestrial stations, wherein at least some of frequencies of the satellite uplink coincide with, and may be used simultaneously with, the frequencies of the terrestrial uplink.

10. The system of claim 1, wherein the satellite links include a satellite downlink, for transmissions to the terminals from the satellite, and the terrestrial links include a terrestrial downlink, for transmissions to the terminals from the terrestrial stations, wherein at least some of the frequencies of the satellite downlink coincide with, and may be used simultaneously with, the frequencies of the terrestrial downlink.

11. The system of claim 1, wherein at least some of the terminals are arranged to cancel, from the satellite downlink, interference from the terrestrial downlink, and/or to cancel, from the terrestrial downlink, interference from the satellite downlink.

12. The system of claim 1, wherein the satellite earth station, or a node connected thereto, is arranged to cancel, from the satellite uplink, interference from the terrestrial uplink.

13. The system of claim 1, wherein at least one of the terrestrial stations, or a node connected thereto, is arranged to cancel, from the terrestrial uplink, interference from the satellite uplink.

14. The system of claim 1, wherein the channels within the satellite links are allocated independently from channels within the terrestrial links.

15. The system claim 1, wherein each of the terrestrial stations generates a plurality of beams defining different sectors.

16. The system of claim 15, wherein the frequencies are re-used between each of the plurality of beams.

17. The system of claim 1, wherein the satellite antenna is arranged to generate one or more beams directed so as to inhibit interference to or from the terrestrial stations.

18. The system of claim 17, wherein the one or more beams generated by the satellite antenna are directed towards the satellite.

19. A vehicle arranged for use in the system of claim 1.

20. A satellite earth station, or a node connected thereto, for use in the system of claim 1.

21. A terrestrial station, or a node connected thereto, for use in the system of claim 1.

22. A method of operating the system of claim 1, in which method the terrestrial frequencies and satellite frequencies are allocated without coordination therebetween.