Antenna system facilitating reduction of interfering signals

Patent metadata

Field	Value
Publication number	US-9647345-B2
Application number	US-201314058855-A
Country	US
Kind code	B2
Filing date	Oct 21, 2013
Priority date	Oct 21, 2013
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

Described embodiments include an antenna system and method. The antenna system includes a surface scattering antenna that has an electromagnetic waveguide structure and a plurality of electromagnetic wave scattering elements. The plurality of electromagnetic wave scattering elements are distributed along the waveguide structure, have a respective activatable electromagnetic response to a guided propagating electromagnetic wave, and produce a controllable radiation pattern. A gain definition circuit defines a radiation pattern configured to acquire a possible interfering signal. The defined antenna radiation pattern has a field of view covering at least a portion of an undesired field of view of an associated antenna. An antenna controller establishes the defined radiation pattern in the surface scattering antenna by activating the respective electromagnetic response of selected electromagnetic wave scattering elements. A correction circuit reduces an influence of the received possible interfering signal in a contemporaneously received signal by the associated antenna.

First claim

The invention claimed is:

1. An antenna system comprising:
a surface scattering antenna including:
an electromagnetic waveguide structure; and
a plurality of electromagnetic wave scattering elements distributed along the waveguide structure and operable in combination to produce a controllable radiation pattern;
a gain definition circuit configured to define a radiation pattern configured to receive a possible interfering signal transmitted within an operating frequency band of an associated antenna, the associated antenna having a field of view that includes a desired field of view and an undesired field of view, and the defined antenna radiation pattern having a field of view covering at least a portion of the undesired field of view of the associated antenna, wherein the undesired field of view includes the possible interfering signal, and the desired field of view includes a target signal;
an antenna controller configured to establish the defined radiation pattern in the surface scattering antenna by activating a respective electromagnetic response of selected electromagnetic wave scattering elements of the plurality of electromagnetic wave scattering elements; and
a correction circuit configured to reduce an influence of the received possible interfering signal in a contemporaneously received signal by the associated antenna.

2. The system of claim 1 , wherein the plurality of electromagnetic wave scattering elements have an inter-element spacing substantially less than a free-space wavelength of a highest operating frequency of the surface scattering antenna, and each electromagnetic wave scattering element of the plurality of electromagnetic wave scattering elements has a respective activatable electromagnetic response to a guided wave propagating in the waveguide structure.

3. The system of claim 2 , wherein the inter-element spacing of the electromagnetic scattering elements includes at least three electromagnetic scattering elements per the free-space wavelength.

4. The system of claim 2 , wherein the inter-element spacing of the electromagnetic scattering elements includes at least five electromagnetic scattering elements per the free-space wavelength.

5. The system of claim 1 , wherein the surface scattering antenna includes a surface scattering antenna having a thin planar dimension relative to a planar dimension of the associated antenna.

6. The system of claim 1 , wherein the aperture of the surface scattering antenna is less than 50% of the aperture of the associated antenna.

7. The system of claim 1 , wherein the surface scattering antenna includes a surface scattering antenna configured to generate an adjustable or reconfigurable radiation pattern.

8. The system of claim 1 , wherein the surface scattering antenna includes an omnidirectional or bidirectional surface scattering antenna.

9. The system of claim 1 , wherein the electromagnetic wave scattering elements include discrete electromagnetic wave scattering elements.

10. The system of claim 1 , wherein the electromagnetic wave scattering elements include electromagnetic wave scattering or radiating elements.

11. The system of claim 1 , wherein the electromagnetic wave scattering elements include metamaterial wave scattering elements.

12. The system of claim 1 , wherein the electromagnetic wave scattering elements include electromagnetic wave transmitting elements.

13. The system of claim 1 , wherein the electromagnetic wave scattering elements include electromagnetic wave receiving elements.

14. The system of claim 1 , wherein the electromagnetic wave scattering elements are exposed to a propagation path of the electromagnetic waveguide structure.

15. The system of claim 1 , wherein the electromagnetic wave scattering elements include electromagnetic wave scattering elements respectively having at least two individually controllable electromagnetic responses to a guided wave propagating in the waveguide structure.

16. The system of claim 1 , wherein the plurality of electromagnetic wave scattering elements are operable in combination to produce a dynamically controllable radiation pattern.

17. The system of claim 1 , wherein the plurality of electromagnetic wave scattering elements are operable in combination to produce a variable radiation pattern providing localization on the possible interfering signal.

18. The system of claim 1 , wherein the gain definition circuit includes a gain definition circuit configured to define an antenna radiation pattern with a field of view shaped to facilitate searching at least a portion of the undesired field of view of the associated antenna for the possible interfering signal.

19. The system of claim 1 , wherein the gain definition circuit includes a gain definition circuit configured to define a series of antenna radiation patterns with fields of view shaped to facilitate searching at least a portion of the undesired field of view of the associated antenna for the possible interfering signal.

20. The system of claim 1 , wherein the gain definition circuit includes a gain definition circuit configured to define an antenna radiation pattern with a field of view shaped to localize at least a portion of the undesired field of view of the associated antenna for the possible interfering signal.

21. The system of claim 1 , wherein the gain definition circuit is further configured to instruct the antenna controller to implement the defined radiation pattern.

22. The system of claim 1 , wherein the undesired field of view of the associated antenna includes a terrestrial or low altitude region.

23. The system of claim 1 , wherein the undesired field of view of the associated antenna includes a field of view away from a potential source of the target signal.

24. The system of claim 1 , wherein the desired field of view of the associated antenna includes a field of view that includes a source of the target signal.

25. The system of claim 1 , wherein the antenna controller is further configured to implement the defined radiation pattern.

26. The system of claim 1 , wherein the antenna controller is configured to establish at least two radiation patterns in the surface scattering antenna by dynamically controlling the respective electromagnetic responses of the electromagnetic wave scattering elements of the plurality of electromagnetic wave scattering elements.

27. The system of claim 1 , wherein the antenna controller is configured to establish the defined radiation pattern in the surface scattering antenna by applying a bias activating the respective electromagnetic response of the electromagnetic wave scattering elements of the plurality of electromagnetic wave scattering elements.

28. The system of claim 1 , wherein the correction circuit is further configured to detect the possible interfering signal.

29. The system of claim 1 , wherein the associated antenna includes an associated skyward or hemispherically sensitive antenna configured to receive electromagnetic signals transmitted by an airborne or spacebome source.

30. The system of claim 1 , wherein the correction circuit is configured to cancel a component of the received possible interfering signal in the contemporaneously received signal by the associated antenna.

31. The system of claim 1 , wherein the correction circuit is configured to subtr

Assignees

• Elwha Llc

Inventors

• Hyde Roderick A
• Kare Jordin T
• Wood Jr Lowell L

Classifications

• H01Q15/0053 Primary

  Selective devices used as spatial filter or angular sidelobe filter · CPC title

• H01Q13/20

  Non-resonant leaky-waveguide or transmission-line antennas; Equivalent structures causing radiation along the transmission path of a guided wave · CPC title

• H01Q3/443

  varying the phase velocity along a leaky transmission line (frequency scanning H01Q3/22; non-resonant leaky-waveguide or transmission-line aerials H01Q13/20) · CPC title

• H01Q15/0086

  said selective devices having materials with a synthesized negative refractive index, e.g. metamaterials or left-handed materials · CPC title

• H01Q1/28

  Adaptation for use in or on aircraft, missiles, satellites, or balloons · CPC title