Shorted annular patch antenna with shunted stubs

• US 10,205,240 B2
• Filed: 09/30/2015
• Issued: 02/12/2019
• Est. Priority Date: 09/30/2015
• Status: Active Grant

• Current Assignee: Mitre Corporation
• Original Assignee: Mitre Corporation
• Inventors: McMichael, Ian T., Lundberg, Erik T., Kolak, Frank S.
• Primary Examiner(s): Phan, Tho G
• Assistant Examiner(s): Holecek, Patrick
• Application Number:
  US14/871,880
• Publication Number:
  US 20170093042A1
• Time in Patent Office: 1,231 Days
• CPC Class Codes: H01Q 5/40 Imbricated or interleaved structures; Combined or electromagnetically coupled arrangements, e.g. comprising two or more non-connected fed radiating elements
• CPC Class Codes: H01Q 9/0414 in a stacked or folded configuration
• CPC Class Codes: H01Q 9/0428 radiating a circular polarised wave
• CPC Class Codes: H01Q 9/0435 using two feed points
• CPC Class Codes: H01Q 9/0464 Annular ring patch

Abstract

A microstrip antenna for circularly polarized radiation including a substrate, a ground layer disposed on a first side of the substrate, a first radiating layer disposed on a second side of the substrate opposite the first side, one or more first electrically conductive pathways extending from the ground layer to the first radiating layer, wherein the one or more first electrically conductive pathways form a ring about an axis, one or more second electrically conductive pathways extending from the ground layer to the first radiating layer, wherein the one or more second electrically conductive pathways are disposed along a portion of a first line extending outwardly from the ring, and a feed conductor for connecting the antenna to a feed line.

Claims

1. A microstrip antenna comprising:

a substrate;

a ground layer disposed on a first side of the substrate;

a first radiating layer disposed on a second side of the substrate opposite the first side;

one or more first electrically conductive pathways extending from the ground layer to the first radiating layer, wherein the one or more first electrically conductive pathways form a ring about an axis;

a feed conductor for connecting the antenna to a feed line; and

one or more second electrically conductive pathways extending from the ground layer to the first radiating layer, wherein the one or more second electrically conductive pathways are oriented with respect to the feed conductor so as to generate a circularly polarized radiation field in response to receiving an electrical signal through the feed conductor and wherein the one or more second electrically conductive pathways form a first line that extends radially from the ring and stops short of an outer perimeter of the first of the first radiating layer.

2. The microstrip antenna of claim 1, wherein the first line intersects the axis of the ring.

3. The microstrip antenna of claim 1, wherein a second line intersecting the feed pin and the axis forms an acute angle with the first line.

4. The microstrip antenna of claim 3, wherein the acute angle is in a range from 30 to 60 degrees.

5. The microstrip antenna of claim 3, wherein the acute angle is in a range from 40 to 50 degrees.

6. The microstrip antenna of claim 3, wherein the acute angle is about 45 degrees.

7. The microstrip antenna of claim 1, wherein first radiating layer is circular.

8. The microstrip antenna of claim 1, wherein the one or more first electrically conductive pathways comprise a plurality of conductive vias extending through the thickness of the substrate.

9. The microstrip antenna of claim 8, wherein the plurality of conductive vias comprises circumferential spacing of less than one-twentieth of a resonant frequency wavelength of the radiating layer.

10. The microstrip antenna of claim 1, wherein the one or more second electrically conductive pathways comprise a plurality of conductive vias extending through the thickness of the substrate.

11. The microstrip antenna of claim 1, wherein the axis extends perpendicularly to the substrate.

12. The microstrip antenna of claim 1, wherein the microstrip antenna is configured with an operating frequency gain null extending circumferentially about the axis.

13. The microstrip antenna of claim 12, wherein the gain null is at least 45 degrees from the axis.

14. The microstrip antenna of claim 12, wherein the gain null is at least 80 degrees from the axis.

15. The microstrip antenna of claim 12, wherein the gain null comprises a gain that is at least 10 decibels relative to an isotropic antenna (dBi) less than a gain at a zenith of the antenna.

16. The microstrip antenna of claim 15, wherein the gain is at least 20 dBi less than the gain at the zenith of the antenna.

17. The microstrip antenna of claim 1, comprising:

a second substrate disposed on the first radiating layer;

a second radiating layer disposed on a side of the second substrate opposite the first radiating layer;

one or more third electrically conductive pathways extending from the first radiating layer to the second radiating layer, wherein the one or more third electrically conductive pathways form a second ring about a second axis;

one or more fourth electrically conductive pathways extending from the first radiating layer to the second radiating layer, wherein the one or more fourth electrically conductive pathways are disposed along a portion of a second line extending outwardly from the second ring; and

a second feed conductor electrically connected to the feed conductor, the second feed conductor configured to provide radiative energy to the second radiating layer.