COMPACT RADIATING ELEMENT HAVING RESONANT CAVITIES

• US 20130207859A1
• Filed: 04/29/2011
• Published: 08/15/2013
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: Centre National De La Recherche Scientifique, Thales SA
• Original Assignee: Centre National De La Recherche Scientifique, Thales SA
• Inventors: Legay, Herv, Sauleau, Ronan, Caille, Grard, Muhammad, Shoaib
• Granted Patent: US 9,843,099 B2
• Time in Patent Office: Days
• US Class Current: 343/756
• CPC Class Codes: H01Q 1/405 Radome integrated radiating elements
• CPC Class Codes: H01Q 1/528 reducing the re-radiation of a support structure in a parabolic reflector antenna H01Q19/023
• CPC Class Codes: H01Q 13/00 Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
• 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 15/0026 said selective devices having a stacked geometry or having multiple layers
• CPC Class Codes: H01Q 15/24 Polarising devices; Polarisation filters H01Q15/12, H01Q15/22 take precedence
• CPC Class Codes: H01Q 15/244 converting a linear polarised wave into a circular polarised wave guided wave H01P1/17

Abstract

A radiating element is provided, for example for array antenna, having stacked resonant cavities of Pérot-Fabry type, of compact structure, a lower cavity being fed by excitation means, the radiating element being characterized in that corrugations are formed substantially below a first earth plane delimiting in its lower part the upper resonant cavity. A radiating element structure of improved compactness is also proposed, whose upper cavity is surmounted by a polarizing radome.

Claims

1. A radiating element comprising:

at least two concentric resonant cavities formed by a lower cavity fed by excitation means, and an upper cavity stacked on the lower cavity, each of said resonant cavities being delimited in its lower part by an earth plane, in its lateral part by a lateral wall, at least the upper cavity being delimited in its upper part by a first essentially plane cap, wherein the corrugations, being essentially of cylindrical shape and concentric with the resonant cavities, are formed substantially below the first earth plane of the upper resonant cavity.

2. The radiating element as claimed in claim 1, wherein the lateral wall is of essentially cylindrical shape.

3. The radiating element as claimed in claim 1, wherein the lateral wall is of essentially conical shape.

4. The radiating element as claimed in claim 1, wherein the lower cavity is also delimited in its upper part, substantially at the level of the lower part of the upper cavity, by a second cap.

5. The radiating element as claimed in claim 1, wherein the earth planes, the caps, the lateral walls and the corrugations are essentially made of a metallic material.

6. The radiating element as claimed in claim 1, wherein the caps are formed by a partially reflecting surface.

7. The radiating element as claimed in claim 1, wherein the caps are formed by a metallic grid.

8. The radiating element as claimed in claim 1, wherein the caps are formed by a dielectric material.

9. The radiating element as claimed in claim 1, wherein a polarizing radome is produced in the upper part of the upper cavity.

10. The radiating element, as claimed in claim 9, wherein the polarizing radome is formed by two essentially plane frequency-selective polarizing surfaces being polarizing FSSs, disposed parallel to one another, and parallel to and substantially above said first cap.

11. The radiating element as claimed in claim 10, wherein each polarizing FSS is formed by a metallic plate comprising a plurality of slots.

12. The radiating element as claimed in claim 10, wherein each polarizing FSS is formed by a metallic plate comprising a plurality of cross-slot cells.

13. The radiating element as claimed in claim 10, wherein each polarizing FSS is formed by a metallic plate comprising a plurality of cross-slot cells disposed according to a periodic pattern on the surface of the metallic plate.

14. The radiating element as claimed in claim 1, wherein the lateral walls and the corrugations are cylindrical with circular cross section.

15. The radiating element as claimed in claim 1, wherein said excitation means comprise at least one feed guide concentric with the resonant cavities and emerging directly, or via matching means, in the lower cavity.

16. The radiating element (30, 50) as claimed in claim 1, wherein said excitation means comprise at least one dual feed formed by two lateral waveguides emerging in a symmetric manner with respect to the main axis of the lower cavity, substantially at the level of the lateral wall of the lower cavity, the signals conveyed by the excitation means being tuned phase-wise in such a way that the undesirable higher modes are filtered.

17. The radiating element as claimed in claim 1, wherein said excitation means comprise at least one feed guide concentric with the resonant cavities and emerging directly, or via matching means, in the lower cavity, and at least one dual feed formed by two lateral waveguides emerging in a symmetric manner with respect to the main axis of the lower cavity, substantially at the level of the lateral wall of the lower cavity, the signals conveyed by the excitation means being tuned phase-wise in such a way that the undesirable higher modes are filtered.

18. The radiating element as claimed in claim 1, wherein a polarizing radome is produced above the upper cavity, the polarizing radome being essentially of cylindrical shape and concentric with the resonant cavities.

19. The radiating element as claimed in claim 18, wherein said polarizing radome is essentially of cylindrical shape with square cross section.

20. An array antenna comprising one or more radiating elements as claimed in claim 1.