NZ756617B2 - Coverage area adjustment to adapt satellite communications - Google Patents

Coverage area adjustment to adapt satellite communications Download PDF

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Publication number
NZ756617B2
NZ756617B2 NZ756617A NZ75661717A NZ756617B2 NZ 756617 B2 NZ756617 B2 NZ 756617B2 NZ 756617 A NZ756617 A NZ 756617A NZ 75661717 A NZ75661717 A NZ 75661717A NZ 756617 B2 NZ756617 B2 NZ 756617B2
Authority
NZ
New Zealand
Prior art keywords
native
antenna
feed
antenna pattern
feed element
Prior art date
Application number
NZ756617A
Other versions
NZ756617A (en
Inventor
Aaron Mendelsohn
Donald Runyon
Original Assignee
Viasat Inc
Filing date
Publication date
Application filed by Viasat Inc filed Critical Viasat Inc
Priority to NZ787007A priority Critical patent/NZ787007A/en
Priority claimed from PCT/US2017/026839 external-priority patent/WO2018190794A1/en
Publication of NZ756617A publication Critical patent/NZ756617A/en
Publication of NZ756617B2 publication Critical patent/NZ756617B2/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/27—Adaptation for use in or on movable bodies
    • H01Q1/28—Adaptation for use in or on aircraft, missiles, satellites, or balloons
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/27—Adaptation for use in or on movable bodies
    • H01Q1/28—Adaptation for use in or on aircraft, missiles, satellites, or balloons
    • H01Q1/288—Satellite antennas
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
    • H01Q19/12—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave
    • H01Q19/17—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave the primary radiating source comprising two or more radiating elements
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q25/00—Antennas or antenna systems providing at least two radiating patterns
    • H01Q25/007—Antennas or antenna systems providing at least two radiating patterns using two or more primary active elements in the focal region of a focusing device
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H01Q3/02—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical movement of antenna or antenna system as a whole
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H01Q3/12—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems
    • H01Q3/16—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying relative position of primary active element and a reflecting device
    • H01Q3/18—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying relative position of primary active element and a reflecting device wherein the primary active element is movable and the reflecting device is fixed
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H01Q3/12—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems
    • H01Q3/16—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying relative position of primary active element and a reflecting device
    • H01Q3/20—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying relative position of primary active element and a reflecting device wherein the primary active element is fixed and the reflecting device is movable
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/185—Space-based or airborne stations; Stations for satellite systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/185—Space-based or airborne stations; Stations for satellite systems
    • H04B7/1851—Systems using a satellite or space-based relay
    • H04B7/18515—Transmission equipment in satellites or space-based relays
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/204—Multiple access
    • H04B7/2041—Spot beam multiple access

Abstract

The described features generally relate to adjusting a native antenna pattern of a satellite to adapt communications via the satellite. The satellite comprises an antenna assembly with a plurality of antenna feed elements. A communications service may be provided via a first and second plurality of beamformed spot beams. The first plurality of beamformed spot beams are based at least in part on a first beamforming configuration and a first native antenna pattern of the antenna assembly. The first native antenna pattern corresponds to a first defocused position of a feed array assembly of the antenna assembly relative to a reflector of the antenna assembly, and the first native antenna pattern comprises a composite of first native feed element patterns of the plurality of antenna feed elements.

Claims (51)

What is claimed is:
1. A method for communications at a communications satellite having an antenna assembly with a plurality of antenna feed elements, the method comprising: transmitting a first plurality of feed element signals generated from a first plurality of spot beam signals according to a first native antenna pattern of the plurality of antenna feed elements, the first native antenna pattern corresponding to a first defocused position of a feed array assembly of the antenna assembly relative to a reflector of the antenna assembly, and the first native antenna pattern comprising a composite of first native feed element patterns of the plurality of antenna feed elements; commanding a change from the first native antenna pattern of the plurality of antenna feed elements to a second native antenna pattern of the plurality of antenna feed elements, the second native antenna pattern corresponding to a second defocused position of the feed array assembly relative to the reflector, and the second native antenna pattern comprising a composite of second native feed element patterns of the plurality of antenna feed elements, wherein a given antenna feed element of the plurality of antenna feed elements is associated with one of the first native feed element patterns and one of the second native feed element patterns, and wherein the one of the second native feed element patterns is different from the one of the first native feed element patterns; transmitting a second plurality of feed element signals generated from a second plurality of spot beam signals according to the second native antenna pattern of the plurality of antenna feed elements.
2. The method of claim 1, wherein commanding the change from the first native antenna pattern to the second native antenna pattern comprises: commanding an actuator of the communications satellite for providing the change from the first native antenna pattern to the second native antenna pattern.
3. The method of claim 2, wherein commanding the actuator to provide the change from the first native antenna pattern to the second native antenna pattern comprises: commanding a spatial adjustment between the reflector of the antenna assembly and the feed array assembly of the antenna assembly comprising the plurality of antenna feed elements.
4. The method of claim 3, wherein the actuator is coupled between the reflector of the antenna assembly and the feed array assembly.
5. The method of claim 2, wherein commanding the change from the first native antenna pattern to the second native antenna pattern comprises: commanding a linear actuator coupled between the reflector and the feed array assembly to change from a first length to a second length.
6. The method of claim 5, further comprising: commanding a secondary actuator coupled between the feed array assembly and the reflector to provide the second native antenna pattern, the commanding of the secondary actuator causing a change in relative position between the feed array assembly and the reflector about an axis different from an axis of the linear actuator.
7. The method of claim 1, wherein one or both of the first defocused position or the second defocused position is associated with one or more of the plurality of antenna feed elements being located between the reflector and a focal region of the reflector.
8. The method of claim 2, wherein commanding the actuator to provide the change from the first native antenna pattern to the second native antenna pattern comprises: commanding an adjustment to a focal region of the reflector of the antenna assembly.
9. The method of any one of claims 1 to 8, wherein the first native antenna pattern is associated with a first boresight direction of the antenna assembly, and the second native antenna pattern is associated with a second boresight direction of the antenna assembly that is different from the first boresight direction.
10. The method of any one of claims 1 to 9, wherein the first native antenna pattern is associated with a first native feed element pattern beamwidth of the given antenna feed element, and the second native antenna pattern is associated with a second native feed element pattern beamwidth of the given antenna feed element that is different from the first native feed element pattern beamwidth.
11. The method of any one of claims 1 to 10, wherein the first native antenna pattern is associated with a first amount of overlap of native feed element patterns of two or more antenna feed elements of the antenna assembly, and the second native antenna pattern is associated with a second, different amount of overlap of the native feed element patterns of the two or more antenna feed elements of the antenna assembly.
12. The method of any one of claims 1 to 8, further comprising: adjusting an orbital characteristic of the communications satellite prior to transmitting the second plurality of feed element signals.
13. The method of any one of claims 1 to 8, wherein the communications satellite is at a same geostationary orbital position while transmitting the first plurality of feed element signals and while transmitting the second plurality of feed element signals.
14. The method of any one of claims 1 to 8, wherein: the communications satellite is at a first geostationary orbital position while transmitting the first plurality of feed element signals; commanding the change from the first native antenna pattern to the second native antenna pattern comprises commanding the communications satellite to move from the first geostationary orbital position to a second, different geostationary orbital position; and the communications satellite is at the second geostationary orbital position while transmitting the second plurality of feed element signals.
15. The method of any of claims 1 to 14, wherein the communications satellite comprises a second antenna assembly with a second plurality of antenna feed elements, the method further comprising: transmitting a third plurality of feed element signals generated from a third plurality of spot beam signals according to a third native antenna pattern of the second plurality of antenna feed elements, the third native antenna pattern of the second plurality of antenna feed elements comprising a composite of third native feed element patterns of the second plurality of antenna feed elements.
16. The method of any of claims 1 to 15, wherein transmitting the first plurality of feed element signals or the second plurality of feed element signals comprises one or both of: transmitting feed element signals to a plurality of access node terminals; or transmitting feed element signals to a plurality of user terminals.
17. The method of any of claims 1 to 16, wherein the first plurality of feed element signals are determined based at least in part on applying a first beamforming weight set to the first plurality of spot beam signals, and the second plurality of feed element signals are determined based at least in part on applying a second beamforming weight set to the second plurality of spot beam signals, the first beamforming weight set being different from the second beamforming weight
18. A communications satellite comprising: means for transmitting a first plurality of feed element signals generated from a first plurality of spot beam signals according to a first native antenna pattern of a plurality of antenna feed elements, the first native antenna pattern corresponding to a first defocused position of a feed array assembly of an antenna assembly relative to a reflector of the antenna assembly, and the first native antenna pattern comprising a composite of first native feed element patterns of the plurality of antenna feed elements; means for commanding a change from the first native antenna pattern of the plurality of antenna feed elements to a second native antenna pattern of the plurality of antenna feed elements, the second native antenna pattern corresponding to a second defocused position of the feed array assembly relative to the reflector, and the second native antenna pattern comprising a composite of second native feed element patterns of the plurality of antenna feed elements, wherein a given antenna feed element of the plurality of antenna feed elements is associated with one of the first native feed element patterns and one of the second native feed element patterns, and wherein the one of the second native feed element patterns is different from the one of the first native feed element patterns; means for transmitting a second plurality of feed element signals generated from a second plurality of spot beam signals according to the second native antenna pattern of the plurality of antenna feed elements.
19. The communications satellite of claim 18, wherein the means commanding the change from the first native antenna pattern to the second native antenna pattern comprises: means for commanding an actuator of the communications satellite for providing the change from the first native antenna pattern to the second native antenna pattern.
20. The communications satellite of claim 19, wherein the means for commanding the actuator to provide the change from the first native antenna pattern to the second native antenna pattern comprises: means for commanding a spatial adjustment between the reflector of the antenna assembly and the feed array assembly of the antenna assembly comprising the plurality of antenna feed elements.
21. The communications satellite of claim 20, wherein the actuator is coupled between the reflector of the antenna assembly and the feed array assembly.
22. The communications satellite of claim 20, wherein the actuator comprises a linear actuator coupled between the reflector and the feed array assembly.
23. The communications satellite of claim 22, further comprising: means for commanding the linear actuator to change from a first length to a second length.
24. The communications satellite of claim 22, further comprising: a secondary actuator coupled between the feed array assembly and the reflector.
25. The communications satellite of claim 24, further comprising: means for commanding the secondary actuator to provide the second native antenna pattern, the commanding of the secondary actuator causing a change in relative position between the feed array assembly and the reflector about an axis different from an axis of the linear actuator.
26. The communications satellite of claim 18, wherein one or both of the first defocused position or the second defocused position is associated with one or more of the plurality of antenna feed elements being located between the reflector and a focal region of the reflector.
27. The communications satellite of claim 19, wherein the means for commanding the actuator to provide the change from the first native antenna pattern to the second native antenna pattern comprises: means for commanding an adjustment to a focal region of a reflector of the antenna assembly.
28. The communications satellite of any one of claims 18 to 27, wherein the first native antenna pattern is associated with a first boresight direction of the antenna assembly, and the second native antenna pattern is associated with a second boresight direction of the antenna assembly that is different from the first boresight direction.
29. The communications satellite of any one of claims 18 to 28, wherein the first native antenna pattern is associated with a first native feed element pattern beamwidth of the given antenna feed element, and the second native antenna pattern is associated with a second native feed element pattern beamwidth of the given antenna feed element that is different from the first native feed element pattern beamwidth.
30. The communications satellite of any one of claims 18 to 29, wherein the first native antenna pattern is associated with a first amount of overlap of native feed element patterns of two or more antenna feed elements of the antenna assembly, and the second native antenna pattern is associated with a second, different amount of overlap of the native feed element patterns of the two or more antenna feed elements of the antenna assembly.
31. The communications satellite of any one of claims 18 to 27, further comprising: means for adjusting an orbital characteristic of the communications satellite prior to transmitting the second plurality of feed element signals.
32. The communications satellite of any one of claims 18 to 27, wherein the means for transmitting the first plurality of feed element signals and the means for transmitting the second plurality of feed element signals are operable at a same geostationary orbital position.
33. The communications satellite of any one of claims 18 to 27, wherein: the means for transmitting the first plurality of feed element signals is operable at a first geostationary orbital position; the means for commanding the change from the first native antenna pattern to the second native antenna pattern comprises means for commanding the communications satellite to move from the first geostationary orbital position to a second, different geostationary orbital position; the means for transmitting the second plurality of feed element signals is operable at the second geostationary orbital position.
34. The communications satellite of any one of claims 18 to 33, further comprising: a second antenna assembly with a second plurality of antenna feed elements; and means for transmitting a third plurality of feed element signals generated from a third plurality of spot beam signals according to a third native antenna pattern of the second plurality of antenna feed elements, the third native antenna pattern of the second plurality of antenna feed elements comprising a composite of third native feed element patterns of the second plurality of antenna feed elements.
35. The communications satellite of any one of claims 18 to 34, wherein the means for transmitting the first plurality of feed element signals or the means for transmitting the second plurality of feed element signals comprises one or both of: means for transmitting feed element signals to a plurality of access node terminals; or means for transmitting feed element signals to a plurality of user terminals.
36. The communications satellite of any one of claims 18 to 35, wherein the first plurality of feed element signals are determined based at least in part on applying a first beamforming weight set to the first plurality of spot beam signals, and the second plurality of feed element signals are determined based at least in part on applying a second beamforming weight set to the second plurality of spot beam signals, the first beamforming weight set being different from the second beamforming weight set.
37. A method for providing a communications service via a communications satellite having an antenna assembly with a plurality of antenna feed elements, the method comprising: transmitting, to the communications satellite, a first set of signals of the communications service for transmission according to a first native antenna pattern of the plurality of antenna feed elements, the first native antenna pattern corresponding to a first defocused position of a feed array assembly of the antenna assembly relative to a reflector of the antenna assembly, and the first native antenna pattern comprising a composite of first native feed element patterns of the plurality of antenna feed elements; transmitting, to the communications satellite, a command to change from the first native antenna pattern of the plurality of antenna feed elements to a second native antenna pattern of the plurality of antenna feed elements, the second native antenna pattern corresponding to a second defocused position of the feed array assembly relative to the reflector, and the second native antenna pattern comprising a composite of second native feed element patterns of the plurality of antenna feed elements, wherein a given antenna feed element of the plurality of antenna feed elements is associated with one of the first native feed element patterns and one of the second native feed element patterns, and wherein the one of the second native feed element patterns is different from the one of the first native feed element patterns; and transmitting, to the communications satellite, a second set of signals of the communications service for transmission according to the second native antenna pattern of the plurality of antenna feed elements.
38. The method of claim 37, wherein transmitting the command to change from the first native antenna pattern to the second native antenna pattern comprises: commanding an actuator of the communications satellite to provide the change from the first native antenna pattern to the second native antenna pattern.
39. The method of claim 38, wherein commanding the actuator to provide the change from the first native antenna pattern to the second native antenna pattern comprises: commanding a spatial adjustment between the reflector of the antenna assembly and the feed array assembly of the antenna assembly comprising the plurality of antenna feed elements.
40. The method of claim 39, wherein the actuator is coupled between the reflector of the antenna assembly and the feed array assembly.
41. The method of claim 39, wherein the command to change from the first native antenna pattern to the second native antenna pattern comprises: commanding a linear actuator coupled between the reflector and the feed array assembly to change from a first length to a second length.
42. The method of claim 41, wherein transmitting the command to change from the first native antenna pattern to the second native antenna pattern comprises: commanding a secondary actuator coupled between the feed array assembly and the reflector to provide the second native antenna pattern, the commanding of the secondary actuator causing a change in relative position between the feed array assembly and the reflector about an axis different from an axis of the linear actuator.
43. The method of claim 37, wherein one or both of the first defocused position or the second defocused position is associated with one or more of the plurality of antenna feed elements being located between the reflector and a focal region of the reflector.
44. The method of claim 38, wherein commanding the actuator to provide the change from the first native antenna pattern to the second native antenna pattern comprises: commanding an adjustment to a focal region of the reflector of the antenna assembly.
45. The method of any one of claims 37 to 44, wherein the first native antenna pattern is associated with a first boresight direction of the antenna assembly, and the second native antenna pattern is associated with a second boresight direction of the antenna assembly that is different from the first boresight direction.
46. The method of any one of claims 37 to 45, wherein the first native antenna pattern is associated with a first native feed element pattern beamwidth of the given antenna feed element, and the second native antenna pattern is associated with a second native feed element pattern beamwidth of the given antenna feed element that is different from the first native feed element pattern beamwidth.
47. The method of any one of claims 37 to 46, wherein the first native antenna pattern is associated with a first amount of overlap of native feed element patterns of two or more antenna feed elements of the antenna assembly, and the second native antenna pattern is associated with a second, different amount of overlap of the native feed element patterns of the two or more antenna feed elements of the antenna assembly.
48. The method of any one of claims 37 to 44, further comprising: transmitting a command to adjust an orbital characteristic of the communications satellite, wherein transmitting the second set of signals comprises transmitting signals according to the adjusted orbital characteristic.
49. The method of any one of claims 37 to 44, wherein the communications satellite is at a same geostationary orbital position while transmitting the first set of signals and while transmitting the second set of signals.
50. The method of any one of claims 37 to 44, wherein: the communications satellite is at a first geostationary orbital position while transmitting the first set of signals; the commanding the communications satellite to change from the first native antenna pattern to the second native antenna pattern comprises commanding the communications satellite to move from the first geostationary orbital position to a second, different geostationary orbital position; the communications satellite is at the second geostationary orbital position while transmitting the second set of signals.
51. The method of any of claims 37 to 50, wherein the communications satellite comprises a second antenna assembly with a second plurality of antenna feed elements, the method further comprising: transmitting, to the communications satellite, a command to change from a third native antenna pattern of the plurality of antenna feed elements, the third native antenna pattern comprising a composite of third native feed element patterns of the second plurality of antenna feed elements to a fourth native antenna pattern of the second plurality of antenna feed elements, the fourth native antenna pattern comprising a composite of fourth native feed element patterns of the second plurality of antenna feed elements, wherein a given antenna feed element of the second plurality of antenna feed elements is associated with one of the third native feed element patterns and one of the fourth native feed element patterns, and wherein the one of the fourth native feed element patterns is different from the one of the third native feed element patterns.
NZ756617A 2017-04-10 2017-04-10 Coverage area adjustment to adapt satellite communications NZ756617B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
NZ787007A NZ787007A (en) 2017-04-10 2017-04-10 Coverage area adjustment to adapt satellite communications

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2017/026839 WO2018190794A1 (en) 2017-04-10 2017-04-10 Coverage area adjustment to adapt satellite communications

Publications (2)

Publication Number Publication Date
NZ756617A NZ756617A (en) 2024-03-22
NZ756617B2 true NZ756617B2 (en) 2024-06-25

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