Importance

Loading Importance Indicators...

Abstract

A vehicle antenna comprises a transparent, electrically conducting, film between the inner and outer glass sheets of a vehicle window. The film comprises a horizontally elongate principal element substantially parallel to and spaced from the upper edge portion of the window aperture and having an effective horizontal length of an odd multiple of one quarter of a predetermined wavelength and an impedance matching element. The impedance matching element comprises a main portion having a peripheral edge with a horizontal upper portion spaced below the principal element and a remainder spaced from the remaining edge portion of the window aperture so as to form a slot transmission line having an effective length of one half the wavelength, which is preferably in the commercial FM band. The impedance matching element further comprises a narrow vertical portion connecting the main portion to the principal element, so that the slot transmission line is parasitically coupled to the principal element. The impedance matching element covers substantially the entire main viewing area of the window, especially if its upper edge is overlapped by an upper dark tinted region of the window. Thus, (1) the antenna more commercially acceptable due to the uniform appearance of the window, (2) the antenna has superior AM band gain due to its large size, and (3) the film may be effectively provided with an infrared reflecting substance for internal vehicle temperature reduction.

Loading the Abstract Image...

First Claim