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:
May. 11, 1999
Filed:
Sep. 26, 1996
Teruhisa Tsuru, Kameoka, JP;
Harufumi Mandai, Takatsuki, JP;
Seiji Kanba, Otsu, JP;
Koji Shiroki, Shiga-ken, JP;
Kenji Asakura, Shiga-ken, JP;
Abstract
A helical antenna is provided in which a predetermined resonance frequency can be determined at the design stage. The helical antenna includes a conductor which is formed from copper or a copper alloy inside a base in the shape of a rectangular parallelopiped formed from a dielectric material having barium oxide, aluminum oxide and silica as main constituents and which is wound in a helical shape along the length of the base. In such a case, the resonance frequency f0 of the helical antenna and the inductance components L of the conductor satisfy the relationship: ln (L)=A0+A1.times.ln (f0), where ln is a natural logarithm, and A0 and A1 are constants. One end of the conductor is extended onto the surface of the base and forms a power feeding terminal connected to a power feeding terminal formed on the surface of the base for applying a voltage to the conductor, and the other end thereof forms a free end inside the base.