Coplanar patch antenna

• US 4,873,529 A
• Filed: 12/16/1988
• Issued: 10/10/1989
• Est. Priority Date: 12/22/1987
• Status: Expired due to Fees

• Current Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Gibson, Peter J.
• Primary Examiner(s): Carroll, J.
• Assistant Examiner(s): Wimer, Michael C.
• Application Number:
  US07/286,572
• Time in Patent Office: 298 Days
• Field of Search: 343/700 MS, 343/767-771, 343/846, 343/829
• US Class Current: 343/700.0MS
• CPC Class Codes: G11B 33/1486 Control/regulation of the pressure, e.g. the pressure inside the housing of a drive
• CPC Class Codes: H01Q 9/0435 using two feed points

Abstract

A coplanar patch antenna is formed, e.g as a printed circuit, on a dielectric support (1) by a metal patch (2) spaced from a coplanar ground plane (3) by a peripheral slot (4), and in the improvement is series fed by means of a slot line (5). The slot (4) can be made resonant by having a periphery of one wavelength or an odd multiple thereof, and a second slot line (7) can be fed into the slot (4) at a distance of one or an odd multiple of a quarter wavelength from the slot line (5) to provide an independent feed. The arrangement presents a feedpoint impedance of about 50 ohms at the ports (6,8) instead of about 400 ohms in prior arrangements.

Balancing loads or 180 degree hybrid feeds to other quadrature ports (11,12) can be used to correct beam asymmetry due to the slot line feeders (5 and 7).

Claims

1. A coplanar patch antenna including a continuous layer of a dielectric material, a patch of conductive material supported on a major surface of the layer of dielectric material, a ground plane of conductive material supported on said major surface of the layer of dielectric material and substantially surrounding and spaced from the patch of conductive material, and means for feeding electrical signals to the antenna, characterised in that the means for feeding electrical signals to the antenna comprises a slot line formed in said ground plane of conductive material and opening into the space between the ground plane and the patch of conductive material.

2. A coplanar patch antenna as claimed in claim 1, characterised in that the perimeter formed by the space between the ground plane and the patch of conductive material, is substantially one wavelength long at the operating frequency so as to form a resonant arrangement.

3. A coplanar patch antenna as claimed in claim 1, characterised in that the perimeter formed by the space between the ground plane and the patch of conductive material, is substantially an odd multiple of one wavelength long at the operating frequency so as to form a resonant arrangement.

4. A coplanar patch antenna as claimed in claim 1, 2 or 3, characterised in that the patch of conductive material is rectangular.

5. A coplanar patch antenna as claimed in claim 4, characterised in that the patch of conductive material is square.

6. A coplanar patch antenna as claimed in any one of claims 1, 2, or 3 characterised in that a further slot line is formed in said ground plane of conductive material so as to open into the space between the ground plane and the patch of conductive material at a location an odd number of quarter wavelengths around the periphery of the patch of conductive material from the opening for the first-mentioned slot line.

7. A coplanar patch antenna as claimed in claim 4, characterized in that a further slot line is formed in said ground plane of conductive material so as to open into the space between the ground plane and the patch of conductive material at a location an odd number of quarter wavelengths around the periphery of the patch of conductive material from the opening for the first-mentioned slot line.

8. A coplanar patch antenna as claimed in claim 5, characterized in that a further slot line is formed in said ground plane of conductive material so as to open into the space between the ground plane and the patch of conductive material at a location an odd number of quarter wavelengths around the periphery of the patch of conductive material from the opening for the first-mentioned slot line.