A STABILIZED PLATFORM FOR A WIRELESS COMMUNICATION LINK

• US 20160134006A1
• Filed: 06/11/2014
• Published: 05/12/2016
• Est. Priority Date: 06/11/2013
• Status: Active Grant

• Current Assignee: EM Solutions Pty., Ltd. (Electro Optic Systems Holdings Ltd.)
• Original Assignee: EM Solutions Pty., Ltd. (Electro Optic Systems Holdings Ltd.)
• Inventors: Ness, John, Callaghan, Glen, Rutherford, Tui, Harris, Richard
• Granted Patent: US 10,008,759 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01S 3/38 using adjustment of real or effective orientation of directivity characteristic of an antenna or an antenna system to give a desired condition of signal derived from that antenna or antenna system, e.g. to give a maximum or minimum signal G01S3/16, G01S3/28 take precedence
• CPC Class Codes: H01Q 1/1257 using the received signal strength
• CPC Class Codes: H01Q 13/025 Multimode horn antennas; Horns using higher mode of propagation H01Q13/0241 takes precedence; multiple beam H01Q25/04
• CPC Class Codes: H01Q 19/19 comprising one main concave reflecting surface associated with an auxiliary reflecting surface
• CPC Class Codes: H01Q 3/02 using mechanical movement of antenna or antenna system as a whole
• CPC Class Codes: H01Q 3/08 for varying two co-ordinates of the orientation
• CPC Class Codes: H01Q 5/55 for horn or waveguide antennas

Abstract

A terrestrial data communications wireless link includes a first link end that has a first directional antenna, a first beacon and a first redirecting assembly coupled to the first directional antenna. The wireless link also includes a second link end having a second directional antenna, a second beacon and a second redirecting assembly coupled to the second directional antenna. In use the first directional antenna and the second directional antenna are maintained in mutual alignment by the first redirecting assembly redirecting the first directional antenna in response to a signal from the second beacon and the second redirecting assembly redirecting the second directional antenna in response to a signal from the first beacon.

Claims

1. An apparatus comprising a link end for a terrestrial communications link including:

a directional antenna;

a redirecting assembly mounted to the directional antenna;

one or more actuators coupled to the redirecting assembly;

a control system arranged to control the redirecting assembly in response to variations in the strength of a terrestrial beacon signal.

2. An apparatus according to claim 1, including an antenna feed to transmit and receive a main data signal and to receive the beacon signal, the antenna feed including a horn defining a boresight for propagation of the main data signal therealong and second horn parallel thereto to or integrated therewith to receive said beacon signal.

3. An apparatus according to claim 1, including an antenna feed to transmit and receive a main data signal and to receive said beacon signal, the antenna feed including an elongated bore having a boresight for propagation of the main data signal and one or more pairs of slots disposed on either side of the main bore and parallel thereto to receive said beacon signal.

4. An apparatus according to claim 1, wherein the redirecting assembly comprises a two axis gimbal.

5. An apparatus according to claim 4, wherein the control system includes an azimuth control subassembly in communication with a first actuator of said actuators, wherein the first actuator is arranged to vary an azimuth angle of the gimbal.

6. An apparatus according to claim 4, wherein the control system includes an elevation control subassembly in communication with a second actuator of said actuators, wherein the second actuator is arranged to vary an elevation angle of the gimbal.

7. An apparatus according to claim 6, wherein the elevation control subassembly includes an inclinometer.

8. An apparatus according to claim 5, wherein the azimuth control subassembly includes a first gyroscope arranged to sense angular velocity of the directional antenna.

9. An apparatus according to claim 7, wherein the elevation control subassembly includes a second gyroscope arranged to sense angular velocity of the directional antenna.

10. An apparatus according to claim 8 or claim 9 wherein the control system is arranged to estimate drift of said gyroscope and compensate accordingly.

11. An apparatus according to any one of claims 1 to 10, wherein the control system is arranged to implement a control system including an inner velocity loop and an outer position loop.

12. An apparatus according to any one of claims 1 to 11 including a beacon source.

13. An apparatus according to claim 12 wherein the beacon source comprises a wireless signal generator and a feed or beacon antenna coupled thereto wherein the feed or beacon antenna is arranged to produce a wider beamwidth than the directional antenna.

14. An apparatus according to claim 13, wherein the beacon generator comprises a K-band signal generator.

15. An apparatus according to any one of the preceding claims, wherein the control system includes at least one monopulse network.

16. An apparatus according to any one of claims 1 to 15, including a second antenna non-parallel to the directional antenna and arranged to move in concert therewith;

wherein the control system controls the redirecting assembly in response to variations in the beacon signal as received by the second antenna.

17. A terrestrial data communications wireless link including:

a first link end including a first directional antenna, a first beacon and a first redirecting assembly coupled to the first directional antenna; and

a second link end including a second directional antenna, a second beacon and a second redirecting assembly coupled to the second directional antenna;

wherein the first directional antenna and the second directional antenna are maintained in mutual alignment by the first redirecting assembly redirecting the first directional antenna in response to a signal from the second beacon and the second redirecting assembly redirecting the second directional antenna in response to a signal from the first beacon.

18. A terrestrial data communications wireless link comprising:

a first data traffic directional antenna of a first end of the link;

a second data traffic directional antenna of a second end of the link wherein said first antenna and said second antenna point at each other;

a first beacon signal directional antenna of the first end of the link pointed at a beacon transmitter located off a line between said first and second data traffic antennas;

a second beacon signal directional antenna of the second end of the link pointed at the beacon transmitter;

a first redirecting assembly of the first end of the link arranged to redirect said first data traffic antenna and said first beacon antenna;

a second redirecting assembly of the second end of the link arranged to redirect said second data traffic antenna and said second beacon antenna;

wherein the first data traffic directional antenna and the second data traffic directional antenna are maintained in mutual alignment by the first redirecting assembly operating in response to a signal from said beacon received by the first said beacon antenna, and the second redirecting assembly operating in response to a signal from said beacon received by the second said beacon antenna.

19. A method for maintaining a first antenna in a desired direction including:

redirecting the first antenna in response to variations in a beacon signal received at a location proximate or coincident with the first antenna wherein the beacon signal emanates from a remote beacon.

20. A method according to claim 19, wherein the first antenna is mounted to a redirecting assembly arranged for redirection thereof and the step of redirecting the antenna includes controlling actuators of the redirecting assembly.

21. A method according to claim 20, wherein the redirecting assembly comprises a gimbal having first and second axes.

22. A method according to any one of claims 19 to 21 including narrowing the beacon signal beamwidth, subsequent to acquisition thereof, for improved accuracy in redirecting the first antenna.

23. A method according to any one of claims 19 to 22, wherein the first antenna comprises part of a first end of a terrestrial data communication link and said remote beacon is located proximal or coincident with a second antenna comprising a second end of said communication link.

24. A method according to claim 23, wherein the beacon signal beamwidth is greater than a beamwidth associated with a data communication signal of the second antenna.

25. A method according to claim 23 or claim 24 wherein boresights of the first antenna and its beacon receiver antenna are coincident, the method including:

carrying out the step of redirecting the first antenna in response to the beacon signal until the data communication signal is acquired; and

then redirecting the first antenna in response to variations in the data communication signal.

26. A method according to claim 25, wherein the step of redirecting the first antenna in response to variations in the beacon signal includes applying a monopulse process to thereby improve the accuracy with which the first antenna is redirected.

27. A method according to claim 25 including redirecting the first antenna to mechanically scan for a boresight associated with the beacon signal.

28. A software or firmware product comprising tangible machine readable instructions for execution by an electronic processor for implementing a method according to any one of claims 19 to 27.

29. A method according to claim 24, wherein the beacon signal beamwidth is sufficient to accommodate a range of angular perturbations of the first or second antenna from the desired direction.

30. A method according to claim 19, wherein the beacon signal emanates from a beacon located off the desired direction and wherein the beacon signal is received by a second antenna pointed toward the beacon wherein the second beacon antenna is arranged to move in concert with the first antenna.

31. A method for increasing the operational range of a high frequency wireless data communications module comprising the steps of:

mounting said communications module to a back face of an interface assembly;

mounting a front face of the interface assembly to an antenna feed of a platform stabilization assembly to thereby couple the communications module to the antenna feed for receiving and transmitting data signals therefrom;

wherein the back face of the interface assembly is arranged to mate with coupling formations of the communications module and wherein the platform stabilization assembly comprises

a directional antenna;

a redirecting assembly mounted to the directional antenna;

one or more actuators coupled to the redirecting assembly;

a control system arranged to control the redirecting assembly in response to variations in the strength of a terrestrial beacon signal.

32. A method according to claim 31, wherein the interface assembly comprises an interface chassis and an interface plate which comprises the back face of the interface assembly, wherein the interface plate is detachable from the interface assembly for substitution of different interface plates having different communication modules mounted thereto.

33. A method for mounting any one of a plurality of communications modules to a platform stabilization assembly, wherein each of the communications modules is arranged with a different coupling configuration, the method including:

producing a plurality of interface assemblies, each of said assemblies having a back face arranged to mate with a corresponding one of the plurality of communications modules and a common front face arranged to mate with the platform stabilisation assembly;

for a selected one of the communications modules, selecting a corresponding one of the interlace assemblies;

mounting the selected communications module to the selected corresponding interface assembly; and

mounting the interface assembly to the platform stabilisation assembly.

34. A method according to claim 33, wherein one or more of the interface assemblies is comprised of an interface plate and an interface chassis for attachment thereto.

37. An interface assembly according to claim 34 comprising an interface chassis arranged to convey platform stabilization signals and an interface plate which comprises the back face of the interface assembly, wherein the interface plate is detachable from the interface assembly for substitution of different interface plates having different communication modules mounted thereto.

35. An apparatus for coupling any one of a number of different communications modules to an antenna feed of a platform stabilization system, the apparatus comprising:

an interface assembly including an interface chassis having a front face arranged to couple to the antenna feed and an interface plate removably fastened to the interface chassis and having a back face arranged to couple to the communications module;

wherein the interface plate is one of a number of interface plates each having a back face arranged to complement various coupling configurations of the different communications modules

36. An interface assembly including:

a back face for coupling to a communications module; and

a front face arranged for coupling to an antenna feed of a platform stabilization assembly to thereby couple said electronic circuitry thereto and to couple the communications module to the antenna feed for receiving and transmitting data signals therefrom;

wherein the back face is arranged to mate with coupling formations of the communications module.