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:
Feb. 01, 2000
Filed:
May. 26, 1998
Louis Leonard Nagy, Warren, MI (US);
Douglas Courtney Martin, Warren, MI (US);
Michael Jerome Lewis, Southfield, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A vehicle window antenna is a transparent, electrically conducting film disposed between the inner and outer glass sheets of a composite window glass. The antenna has a principal element spaced from the upper edge portion of the window aperture and an impedance matching element extending downward from the principal element to essentially cover the visible area of the window and form a slot transmission line with the remaining edge portion of the window aperture parasitically coupled to the principal element. The large area of the antenna provides a large capacitance producing high gain in a commercial AM band. An essentially transparent planar capacitive coupling member made of an electrically conducting material is affixed on an outer surface of the inner window glass. The capacitive coupling member defines a planar area of at least 100 square centimeters plane parallel with an equivalent planar area of the principal element of the antenna to capacitively couple therewith through one glass sheet and the interposed layer of the window glass. The large capacitive coupling area reduces the impedance at commercial FM wavelengths to an insignificant level to prevent the capacitive coupling member from adversely affecting the impedance matching of the impedance matching element of the antenna. The AM gain lost by capacitive coupling of the antenna is at least partially compensated by high AM gain due to the large area of the antenna. An electrically conducting terminal member extends vertically from the capacitive coupling member near the upper edge of the window aperture on an area of the window glass hidden by vehicle trim.