Ring-slot radiator for broad-band operation
View Patent ↗One embodiment is a ring-slot radiator having: at least one radiating element having a characteristic of dual resonance, double-tuned in which an open ended strip and a cavity are structured to resonate at at least two different frequencies. Another embodiment may have: a ring-slot structure having at least one ring-slot opening on an infinite ground plane that forms a radiating element; a probe-fed strip structure that excites the slot; another ground plane underneath the strip; and a plurality of suppression elements around the ring slot to suppress parallel plate and surface wave modes.
1. An apparatus, comprising:
a ring-slot structure having at least one ring-slot opening on an infinite ground plane that forms a radiating element;
a probe-fed strip structure that excites the slot; another ground plane underneath the strip structure;
a plurality of suppression elements around the ring slot to suppress parallel plate and surface wave modes;
the radiating element having a characteristic of dual resonance, double-tuned in which the strip structure is an open ended strip and both the strip structure and a cavity are structured to resonate at at least two different frequencies; and
two of the suppression elements of the plurality of suppression elements being two reactive posts that are positioned at a 45-degree angle relative to the strip structure.
2. The apparatus according to claim 1 ,
wherein the radiating element has a patch, and
wherein a shape of the patch is one of rectangular and elliptical, and
wherein a shape of the ring-slot structure changes accordingly.
3. The apparatus according to claim 1 , wherein the radiating element has a patch, and wherein a shape of the patch is circular.
4. The apparatus according to claim 1 , wherein the radiating element has a patch, and wherein a shape of the patch is square.
5. The apparatus according to claim 1 , wherein a shape of the radiating element is deformed with notches/ears.
6. The apparatus according to claim 1 , wherein the two reactive posts also function as supports for a patch of the ring-slot structure in the case of air-filled cavity.
7. The apparatus according to claim 1 , wherein the apparatus generates circular polarization radiation using mode degeneracy.
8. An apparatus, comprising:
a ring-slot structure having at least one ring-slot opening on an infinite ground plane that forms a radiating element;
a probe-fed strip structure that excites the slot; another ground plane underneath the strip structure;
a plurality of suppression elements around the ring slot to suppress parallel plate and surface wave modes;
the radiating element having a characteristic of dual resonance, double-tuned in which the strip structure is an open ended strip and both the strip structure and a cavity are structured to resonate at least two different frequencies; and
the radiating element formed by a thin low-loss circuit board, the circuit board and plated through holes thereof suspended above a defined cavity;
wherein two of the suppression elements of the plurality of suppression elements are two reactive posts that are positioned at a 45-degree angle relative to the strip structure.
9. The apparatus according to claim 8 , wherein the suppression elements are vias.
10. The apparatus according to claim 8 , wherein the suppression elements are partial conductors of copper or aluminum plated surfaces.
11. The apparatus according to claim 8 , wherein the strip structure is formed on a substrate, and wherein a substrate material of the substrate is a low permittivity material.
12. The apparatus according to claim 8 ,
wherein the strip structure is formed on an air-substrate, and
wherein a center via holds a circular patch region ring-slot structure on an upper ground plane.
13. The apparatus according to claim 8 , wherein dimensions of a slot radii of the ring-slot opening and the strip structure are structured to provide dual resonance behavior of the ring-slot structure.
14. The apparatus according to claim 8 , wherein, for bandwidth enhancement, another layer of parasitic patches is located above a radiating slot layer of the ring-slot structure.
15. The apparatus according to claim 8 ,
wherein the ring-slot structure has approximately 10 dB return loss bandwidth that is about 21% of an operating frequency, and
wherein the ring-slot structure has a bore-sight gain of about 6 dBi at a center frequency, which corresponds to about 100% aperture efficiency.
16. The apparatus according to claim 8 , wherein the cavity is constructed of very low mass materials.
17. A method, comprising:
forming at least one radiating element from a ring-slot structure having at least one ring-slot opening on an infinite ground plane;
forming a probe-fed strip structure that excites the slot;
forming another ground plane underneath the strip structure;
forming a plurality of suppression elements around the ring slot to suppress parallel plate and surface wave modes; and
obtaining circular polarization using mode degeneracy by placing two of the suppression elements as reactive posts at a 45-degree location relative to the strip structure;
wherein the radiating element has a characteristic of dual resonance, double-tuned in which the strip structure is an open ended strip and both the strip structure and a cavity are structured to resonate at at least two different frequencies.
18. The method according to claim 17 , wherein a shape of the patch of the at least one radiating element is deformed with notches/ears.