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. 26, 2006
Filed:
Jun. 04, 2005
Cheng-wei Lan, Taipei, TW;
Jean-fu Kiang, Taipei, TW;
Jing-je Gau, Taipei, TW;
National Taiwan University, Taipei, TW;
Abstract
A bifilar helical antenna includes an output/input unit formed by disposing a hybrid on a substrate, wherein the surface of the substrate is coated with a metallic conductive layer; the hybrid is a microstrip-line pattern formed by the conductive layer, and it further comprises a ring part and a plurality of transmission ports; and an antenna unit including a shell and an impedance transformer, wherein the shell is a cylindrical hollow tube disposed on the substrate of the output/input unit, on which a first helical line and a parallel second helical line are wound and both the bottom ends of the helical lines are electrically connected together through a resistor; the impedance transformer is composed of a first transmission line and a parallel second transmission line, where both the top ends of the first and the second transmission line are electrically connected to the top end of the first and the second helical line, and both the bottom ends of the first and the second transmission line are electrically connected to different transmission ports of the hybrid, respectively.