Omni-directional antenna

• US 7,443,348 B2
• Filed: 05/30/2007
• Issued: 10/28/2008
• Est. Priority Date: 05/30/2006
• Status: Expired due to Fees

• Current Assignee: Solidica, Inc.
• Original Assignee: Solidica, Inc.
• Inventors: Fortson, Frederick O., Hansen, Richard, Soosik, Greg
• Primary Examiner(s): PHAN, THO GIA
• Application Number:
  US11/755,265
• Publication Number:
  US 20080030406A1
• Time in Patent Office: 517 Days
• Field of Search: 343/700.MS, 343/702, 343/846, 343/815, 343/833, 343/834, 343/829
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 9/32 Vertical arrangement of element H01Q9/40 takes precedence

Abstract

An omni-directional antenna includes an electrically conductive ground plane, an electrically conductive parasitic disc spaced upwardly apart from the ground plane and parallel thereto, and an electrically conductive vertical antenna element extending up through the center of the ground plane and parasitic disc, The vertical element terminates in a tip defining a length above the parasitic disc that is matched to a frequency of interest. The parasitic disc and ground plane are preferably both circular. To prevent electrical connection, the vertical element preferably extends through separate insulators in the parasitic disc and ground plane. The length of the vertical element is matched to a microwave frequency; in particular, the length of the vertical element is proportioned to one-quarter wavelength of the frequency of interest. The invention is particularly suited to microwave frequencies.

Claims

1. An omni-directional antenna comprising:

an electrically conductive ground plane;

an electrically conductive parasitic disc spaced upwardly apart from the ground plane and parallel thereto; and

an electrically conductive vertical antenna element extending up through the center of the ground plane and parasitic disc, the vertical element terminating in a tip defining a length above the parasitic disc that is matched to a frequency of interest.

2. The omni-directional antenna of claim 1, wherein the parasitic disc is circular.

3. The omni-directional antenna of claim 2, wherein the diameter of the parasitic disc is smaller than the length of the vertical element.

4. The omni-directional antenna of claim 1, wherein the ground plane is circular.

5. The omni-directional antenna of claim 4, wherein the diameter of the ground plane is larger than the length of the vertical element.

6. The omni-directional antenna of claim 1, wherein the vertical element extends through an insulator in the parasitic disc to prevent electrical connection thereto.

7. The omni-directional antenna of claim 1, wherein the vertical element extends through an insulator in the ground plane to prevent electrical connection thereto.

8. The omni-directional antenna of claim 1, wherein the length of the vertical element is matched to a microwave frequency.

9. The omni-directional antenna of claim 1, wherein the length of the vertical element is proportioned to one-quarter wavelength of the frequency of interest.

10. The omni-directional antenna of claim 1, wherein the vertical element is perpendicular to the parasitic disc and ground plane.