Miniaturized and reconfigurable CPW square-ring slot antenna including ferroelectric BST varactors

• US 8,957,817 B2
• Filed: 06/06/2012
• Issued: 02/17/2015
• Est. Priority Date: 06/06/2011
• Status: Active Grant

• Current Assignee: University of Dayton
• Original Assignee: University of Dayton
• Inventors: Jiang, Hai, Subramanyam, Guru
• Primary Examiner(s): Ho, Tan
• Application Number:
  US13/489,694
• Publication Number:
  US 20130141295A1
• Time in Patent Office: 986 Days
• Field of Search: 343/767, 343/768, 343/769, 343/745, 343/749, 343/746
• US Class Current: 343/746
• CPC Class Codes: H01P 11/00 Apparatus or processes specially adapted for manufacturing waveguides or resonators, lines, or other devices of the waveguide type
• CPC Class Codes: H01Q 13/103 with variable reactance for tuning the antenna tuning resonant circuits H03J
• CPC Class Codes: H01Q 13/106 Microstrip slot antennas patch antenna elements H01Q9/0407
• CPC Class Codes: H01Q 9/0442 with particular tuning means
• CPC Class Codes: H01Q 9/0464 Annular ring patch
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making

Abstract

A coplanar waveguide (CPW) square-ring slot antenna for use in wireless communication systems is miniaturized and reconfigurable by the integration of ferroelectric (FE) BST (barium strontium titanate) thin film varactors therein. The slot antenna device includes a sapphire substrate, top and bottom metal layers, and a thin ferroelectric BST film layer, where the FE BST varactors are integrated at the back edge of the antenna on the top metal layer.

Claims

1. A CPW square-ring slot antenna having integral ferroelectric BST (barium strontium titanate) varactors on a back edge thereof;

wherein said antenna is miniaturized and reconfigurable.

2. The slot antenna of claim 1 further including a sapphire substrate, a bottom metal layer on said substrate, a BST thin film layer on said bottom metal layer, and a top metal layer;

wherein said antenna and said varactors are included on said top metal layer.

3. The slot antenna of claim 2 wherein said sapphire substrate has a dielectric constant of about 9.7.

4. The slot antenna of claim 2 wherein said top and bottom metal layers are comprised of gold.

5. The slot antenna of claim 2 wherein said top and bottom metal layers comprise titanium, platinum, gold, or combinations thereof.

6. The slot antenna of claim 1 having a size of about 0.12λ

₀×

0.12λ

₀.

7. The slot antenna of claim 1 wherein the frequency of the antenna is reconfigurable from about 5.3 GHz to 5.8 GHz.

8. The slot antenna of claim 1 comprising an inner patch including said back edge, wherein said ferroelectric BST varactors are integrated on said back edge.

9. The slot antenna of claim 1 wherein from 3 to 9 varactors are integrated on said back edge.

10. A method of making a miniaturized and reconfigurable CPW square-ring slot antenna comprising:

providing a sapphire substrate;

applying a bottom metal layer over said sapphire substrate;

depositing a ferroelectric BST thin film over said bottom metal layer;

applying a top metal layer over said BST thin film;

said top metal layer comprising an inner patch including a back edge; and

loading a plurality of ferroelectric BST varactors at the back edge of said top metal layer.

11. The method of claim 10 wherein about 3 to 9 ferroelectric BST varactors are loaded at the back edge of said top metal layer.