The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 29, 1998
Filed:
Aug. 08, 1996
Darrell L Helms, Seminole, FL (US);
James R Sherman, St. Petersburg, FL (US);
Barry B Pruett, St. Petersburg, FL (US);
E-Systems, Inc., Dallas, TX (US);
Abstract
A dual band, stacked microstrip antenna produces circular polarization. A two-layer, 90.degree. microstrip coupler is mounted to a hi-band patch and a lo-band patch and provides two inputs to the antenna to excite two orthogonal linearly polarized radiation patterns in quadrature. The coupler outputs are connected to the antenna by two conducting pins that connect directly to the groundplane of the lower patch. The coupler uses the hi-band patch as a groundplane and is transparent to the radiation from the antenna. An antenna input connector is connected to the coupler input by means of a coaxial line through the center of the antenna. The isolation port is terminated in a surface mounted 50-ohm resister to ground through a quarter wave length open transmission line.