Isolation enhancement technique for dual-polarized probe-fed patch antenna

• US 7,994,985 B2
• Filed: 05/26/2009
• Issued: 08/09/2011
• Est. Priority Date: 05/26/2009
• Status: Active Grant

• Current Assignee: City University of Hong Kong
• Original Assignee: City University of Hong Kong
• Inventors: Luk, Kwai Man, Lau, Ka Leung
• Primary Examiner(s): MANCUSO, HUEDUNG XUAN CAO
• Application Number:
  US12/471,691
• Publication Number:
  US 20100302104A1
• Time in Patent Office: 805 Days
• Field of Search: 343/700.MS, 343/702, 343/846
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 9/0435 using two feed points
• CPC Class Codes: H01Q 9/0457 electromagnetically coupled to the feed line

Abstract

The present invention provides a patch antenna comprising a patch spaced from a ground plane and two L-shaped feed probes. Each feed probe is connected to a respective input port and has a portion extending parallel to the patch. The antenna further includes at least two walls extending from the ground plane towards the patch. The walls are positioned between the L-shaped feed probes so as to permit direct propagation between the input ports and also to create indirect diffraction paths between the input ports that serve to cancel at least a part of said direct propagation.

Claims

1. A patch antenna comprising a patch spaced from a ground plane and two L-shaped feed probes each said feed probe having being connected to a respective input port and having a portion extending parallel to the patch, and at least two walls extending from said ground plane towards said patch, said walls being positioned between said L-shaped feed probes.

2. An antenna as claimed in claim 1 wherein two vertical walls are provided along a line extending at 45°

to each said feed probe.

3. An antenna as claimed in claim 2 wherein said feed probes extend orthogonally with respect to the sides of a square said patch and wherein said walls extend along a line that is diagonal relative to said patch.

4. An antenna as claimed in claim 2 wherein said feed probes are provided at respective corners of a square patch and extend along diagonals relative to said patch, and wherein said walls extend along a line disposed centrally with respect to said square patch.

5. An antenna as claimed in claim 1 wherein each said wall has the same height measured from the ground plane towards said patch, and wherein one wall is longer than the other wall measured in a direction parallel to the ground plane.

6. A patch antenna as claimed in claim 1 wherein said vertical walls are positioned so as to permit direct propagation between said input ports.

7. A patch antenna as claimed in claim 6 wherein said vertical walls are positioned such as to create indirect diffraction paths between said input ports, said indirect paths serving to cancel at least a part of said direct propagation.