Patch antenna with a strip line feed element

• US 4,724,443 A
• Filed: 10/31/1985
• Issued: 02/09/1988
• Est. Priority Date: 10/31/1985
• Status: Expired due to Term

• Current Assignee: X-Cyte Inc.
• Original Assignee: X-Cyte Inc.
• Inventors: Nysen, Paul A.
• Primary Examiner(s): Wise, Robert E.
• Assistant Examiner(s): Johnson, Doris J.
• Application Number:
  US06/793,702
• Time in Patent Office: 831 Days
• Field of Search: 343/700 MS, 343/829, 343/830
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 1/1221 onto a wall
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H01Q 9/045 with particular feeding means for circular polarisation H01Q9/0428

Abstract

A patch-type antenna is disclosed for radiating electromagnetic radiation in the microwave band. The antenna comprises first and second electrically conductive plates which are supported in spaced-apart parallel relationship. The first plate serves as a ground plane, whereas the second plate forms a patch antenna element. A feed element supplies RF energy to the patch antenna without physically contacting it. This feed element is formed by an elongate, electrically conductive strip line arranged between the two plates and extending from one edge of the second plate to an interior point thereof. The length of this feed element, in its longitudinal direction, is approximately equal to one fourth of the wavelength of the EMR radiation by the antenna at the radio frequency applied thereto.

Claims

1. An RF antenna for radiating electromagnetic radiation ("EMR") comprising:

(a) a first electrically conductive plate, which serves as a ground plane;

(b) a second electrically conductive plate, which serves as a patch antenna element, said second plate being supported in spaced-apart, substantially parallel relationship to said first plate;

(c) a first lead, connected to one of said first and said second plates, for electrically connecting said one plate to a ground potential;

(d) at least one elongate, electrically conductive stripline feed element arranged between said first and second plates and extending from a first end at one edge of said second plate to a second end at an interior point thereof, said feed element having a length in its longitudinal direction in the range of λ

/8 to 3 λ

/8, where λ

is the wavelength of EMR at the radio frequency of operation; and

(e) a second lead, directly connected to said first end of said feed element for electrically coupling radio frequency energy into or out of feed element;

whereby said feed element is electrically coupled to one of said first and second plates at said radio frequency to radiate or receive EMR.

2. The antenna defined in claim 1, wherein said length of said feed element is substantially equal to λ

/4.

3. The antenna defined in claim 1, wherein said first plate is at least as large as said second plate.

4. The antenna defined in claim 1, wherein said second plate is rectangular in shape.

5. The antenna defined in claim 1, wherein said feed element extends toward the center of said second plate from a point near the edge of said second plate.

6. The antenna defined in claim 1, further comprising a non-conducting standoff element arranged between said feed element and said first plate at said second end of said feed element.

7. The antenna defined in claim 1, wherein said feed element is arranged substantially equidistantly between, and extends substantially parallel to, said first and said second plates.