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:
Aug. 22, 2000
Filed:
Sep. 10, 1997
Glen J Seward, Cincinnati, OH (US);
Paul E Miller, Spring Lake, MI (US);
R.A. Millier Industries, Inc., Grand Haven, MI (US);
Abstract
An AM/FM/CB/cellular telephone antenna includes a first frequency self-resonant circuit at a position above the lower end of the antenna such that the electrical length of the lower section of the antenna is equivalent to one-quarter wavelength for a frequency in the FM frequency range and a second frequency self-resonant circuit disposed below the first frequency self-resonant circuit. The first self-resonant circuit presents a high impedance in the FM frequency band and the second self-resonant circuit presents a high impedance in the cellular frequency range. The entire length of the antenna is equivalent to one-quarter wavelength in a frequency in the CB frequency band. The antenna wire is wound around a fiberglass core, and the FM self-resonant circuit is formed by a tightly wound, coiled section of the wire together with a thin-walled brass tube extending over the core in the area of the tightly wound section. A thin dielectric film is applied between the tube and the tightly wound section of antenna wire thereby forming a capacitor. There is no direct electrical connection between the antenna wire and the tube, and the capacitance between these elements is essentially only stray capacitance. Two antennas, each comprising two frequency self-resonant circuits, are connected by means of a multiplexing circuit to AM/FM, CB and cellular telephone apparatus.