Electromagnetic interference protection for radomes

Patent metadata

Field	Value
Publication number	US-11764467-B2
Application number	US-202117369364-A
Country	US
Kind code	B2
Filing date	Jul 7, 2021
Priority date	Jan 11, 2019
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

The present disclosure relates to a cover for at least one antenna emitting or sensing electromagnetic radiation in at least one first frequency band, the cover includes at least one first surface facing the antenna and at least one second surface averted to the antenna, where the cover includes at least one substrate being transmissible for electromagnetic radiation and at least one first coating covering the substrate in at least one first area, the first coating being transmissible for electromagnetic radiation of at least the first frequency band, whereas the first coating is reflective for electromagnetic radiation falling onto the second surface and having a frequency within at least one second frequency band.

First claim

What is claimed is:

1. A cover for at least one antenna emitting or sensing electromagnetic radiation in at least one first frequency band, being radar frequency, the cover comprising:
at least one first surface facing the antenna and at least one second surface averted to the antenna;
at least one substrate being transmissible for electromagnetic radiation of the first frequency band and a second frequency band comprising visual light and at least one first coating covering the substrate in at least one first area, the first coating being transmissible for electromagnetic radiation of at least the first frequency band and being reflective for electromagnetic radiation falling onto the second surface and having a frequency within the second frequency band,
wherein the first coating acts as a frequency selective surface bandpass filter trimmed such that electromagnetic radiation of the first frequency band is transmitted, whereas radiation in the second frequency band is reflected, and
wherein the cover further comprises:
at least one covering layer located on a side of the first coating being located averted to the substrate, the covering layer being transparent, at least semitransparent, for the second frequency band, or
at least one second coating, at least partly located between the first coating on the one hand and the antenna on the other hand, the second coating being at least partly non transmissible and/or opaque in the second frequency band.

2. The cover according to claim 1 , wherein at least one of the antenna is a radar antenna, or the first frequency band is 10 GHz to 130 GHz, 20 GHz to 100 GHz, 20 GHz to 30 GHz, 70 GHz to 80 GHz, 90 GHz to 100 GHz, 24 GHz, 77 GHz, or 93 GHz.

3. The cover according to claim 1 , wherein the substrate is transmissible for electromagnetic radiation in at least one third frequency band, wherein the second frequency band is at least partly identical to the third frequency band.

4. The cover according to claim 1 , wherein the first coating is at least one of located between the substrate and the antenna or located on the side of the first surface of the substrate.

5. The cover according to claim 1 , wherein the first coating is located on the side of the second surface of the substrate.

6. The cover according to claim 5 , wherein at least one stress controlling layer is located between the substrate and the first coating.

7. The cover according to claim 1 , wherein at least one of:
the second coating is at least partly located between the substrate on the one hand and the antenna on the other hand, or
the second coating is one or more of at least partly non transmissible, opaque in at least one fourth frequency band or the third frequency band, or transmissible in the first frequency band.

8. The cover according to claim 1 , wherein at least one masking layer at least partly covering the first coating or the substrate, wherein the masking layer is at least partly non transmissible or opaque in at least one fifth frequency band, the second frequency band, the third frequency band or the fourth frequency band, or transmissible in the first frequency band.

9. The cover according to claim 1 , wherein one or more of the second frequency band, the third frequency band or the fourth frequency band, comprises 384 THz to 789 THz or visual light.

10. The cover according to claim 1 , wherein one or more of the second frequency band, the fourth frequency band or the fifth frequency band covers the area of 384 THz to 789 THz, or the third frequency band covers only partly the area of 384 THz to 789 THz.

11. The cover according to claim 1 , wherein the covering layer is transparent or at least semitransparent for one or more of the third, fourth, or fifth frequency band.

12. The cover according to claim 1 , wherein the substrate comprises at least partly at least one of a thermoplastic material, a polycarbonate, polymethylmethacrylate, polyethylene, polyester, polyvinyl chloride, polypropylene, polystyrene, acrylonitrile butadiene styrene, acrylonitrile ethylene styrene, polyacrylate, or a mixture thereof.

13. The cover according to claim 1 , wherein the first coating comprises at least one metallic material, chrome, aluminum, zinc, copper, nickel, vandium, titanium, zirconium, niobium, gold, rhodium, cobalt, manganese, molybdenum, tantalum, silver, or a mixture thereof.

14. The cover according to claim 1 , wherein the first coating comprises at least one repetitive pattern, wherein the pattern comprises a plurality of elements being formed as crosses, circles, squares, stars, rectangles, lines, hexagons, ellipsoids, polygons, annulus, semicircles, circular sectors, triquetra, lune, arbelos, spiral, lemniscates, triangles, or oval forms.

15. The cover according to claim 14 , wherein the elements are formed by, with each other separated, one or more of openings or gaps within the first coating.

16. The cover according to claim 14 , wherein the elements are formed by, with each other separated or not interconnected, areas of the first coating.

17. The cover according to claim 1 , wherein the second coating or the mask layer comprises one or more of at least one thermoplastic, Polycarbonate (PC), Acrylonitrile butadiene styrene (ABS), Acrylnitril-Ethylen-Styrol (AES), or Polycarbonate acrylonitrile butadiene styrene (PCABS).

18. The cover according to claim 1 , wherein the first coating, when viewed onto the second surface of the cover presents at least one logo, character, number, graphical trademark, trademark, decorative design, or decorative pattern.

19. The cover according to claim 1 , wherein the masking layer covers the first coating such that when viewed onto the second surface, only at least a first area of the first coating is visible, wherein the first area has the form of at least one logo, character, number, graphical trademark, trademark, decorative design or decorative pattern, wherein the first area is contiguous or formed by at least partly separated subareas.

20. The cover according to claim 1 , wherein at least one third coating is located on the first surface, between the substrate and the first coating, wherein the third coating is electrically insulating.

21. The cover according to claim 1 , wherein at least one fourth coating is at least one of located on the second surface or a side of the second surface of the substrate, between the substrate and the first coating or the covering layer, or located on the side of the first coating or the covering layer averted to the substrate,
wherein the fourth coating forms a thermal hardcoat including light scattering particles.

22. The cover according to claim 1 , wherein at least one of the first coating reflects more than 50%, more than 75%, more than 85%, more than 90%, or more than 95%, the first coating has at least one edge being at least partly curved, or the first coating comprises, in the area of the edge, at least one resistive loading.

23. A method of producing a cover for at least one antenna emitting and/or sensing electromagnetic radiation in at least one first frequency band being radar frequency, especially a cover according to one of the preceding claims, the method comprising:
one or more of proving or producing at least one substrate being transmissible for electromagnetic radiation of the first frequency band and a second frequency band comprising visual light;
covering the substrate with at least one first coating, wherein the first coating provides a

Assignees

• Motherson Innovations Co Ltd

Inventors

• Caruso Dean
• Edwards Scott Agung
• Belcher Simon
• Fimeri Garry Gordon Leslie
• Stoehr Bastian
• Field Simon David
• Hall Colin
• Symonds Tim

Classifications

• H01Q1/422 Primary

  comprising two or more layers of dielectric material (H01Q1/425 takes precedence) · CPC title

• H01Q1/42 Primary

  Housings not intimately mechanically associated with radiating elements, e.g. radome · CPC title

• H01Q1/3233

  particular used as part of a sensor or in a security system, e.g. for automotive radar, navigation systems · CPC title

• H01Q1/425

  comprising a metallic grid · CPC title

• H01Q15/0013

  said selective devices working as frequency-selective reflecting surfaces, e.g. FSS, dichroic plates, surfaces being partly transmissive and reflective · CPC title