Concealed windshield broadband antenna

Claim 2

An AM-FM broadband radio antenna for a vehicle-mounted receiver comprising in combination: a metallic vehicle body element defining a window opening, a window disposed in the opening, first and second conductors having terminal ends, the conductors being disposed in the opening in reversely symmetrical relation and supported by the window, each of the conductors having a portion relatively closely adjacent but spaced from the metallic body element and a portion relatively remote from the metallic body element, the relatively remote portions serving to develop electrical radio signals in response to intercepted electromagnetic radio waves, the relatively adjacent portions providing a capacitance determined as a function of the length of the relatively adjacent portions and as a function of the spacing of the relatively adjacent portions from the metallic body element, the capacitance having such a value that the relatively adjacent portions serve to tune the relatively remote portions for maximum performance in both the AM band and the FM band, and means electrically connecting the terminal ends of the remote conductor portions and the body element to a receiver in the vehicle.

Claim 3

An AM-FM broadband radio antenna for a vehicle-mounted receiver comprising in combination: a metallic vehicle body element defining a windshield opening, a windshield disposed in the opening, first and second conductors having terminal ends, the conductors being disposed in the opening in reversely symmetrical relation and supported by the windshield, each of the conductors having a first portion extending transversely of the windshield and relatively closely adjacent but spaced from the body element and a second portion extending longitudinally of the windshield and relatively remote from the metallic body element, the second conductor portions serving to develop electrical radio signals in response to intercepted electromagnetic radio waves, the first conductor portions providing a distributed inductance and a distributed capacitance, the distributed inductance determined as a function of the length of the first conductor portions, the distributed capacitance determined as a function of the length of the first conductor portions and as a function of the spacing of the first conductor portions from the metallic body element, the distributed inductance and the distributed capacitance having such values that the first conductor portions serve to tune the second conductor portions for proper impedance matching in the AM band and for maximum resonant response in the FM band, contact means electrically connecting the terminal ends of the second portions, and means electrically connecting the contact means and the body element to a receiver in the vehicle.

Claim 4

An AM-FM broadband radio antenna for a vehicle-mounted receiver comprising in combination: a metallic vehicle body element defining a windshield opening, a windshield disposed in the opening, first and second conductors having terminal ends, the conductors being disposed in the opening in reversely symmetrical relation and supported by the windshield, each of the conductors having a first portion extending transversely of the windshield and relatively closely adjacent but spaced from the body element and a second portion extending longitudinally of the windshield and relatively remote from the metallic body element, the second conductor portions serving to develop electrical radio signals in response to intercepted electromagnetic radio waves, the first conductor portions providing a distributed inductance and a distributed capacitance, the distributed inductance determined as a function of the length of the first conductor portions, the distributed capacitance determined as a function of the length of the first conductor portions and as a function of the spacing of the first conductor portions from the metallic body element, the distributed inductance and the distributed capacitance having such values that the first conductor portions serve to tune the second conductor portions for proper impedance matching in the AM band and for maximum resonant response in the FM band, contact means electrically connecting the terminal ends of the second portions, and means electrically connecting the contact means and the body element to a receiver in the vehicle.

Claim 5

A broadband radio antenna for a vehicle-mounted receiver comprising in combination: a windshield aperture in the vehicle defined by a metallic body element, a laminated windshield of known dielectric constant disposed within the aperture, first and second conductors disposed between the laminates of the windshield, and having transverse portions adjacent but spaced from the body element bounding the upper periphery of the windshield and longitudinal portions extending in spaced parallel fashion along the centerline of the windshield, an antenna lead comprising coaxial center and outer conductors for connecting the first and second conductors to a radio receiver, means adjacent the bottom periphery of the windshield for electrically connecting the longitudinal portions of the first and second conductors to the center conductor, means connecting the body element to the outer conductor, the first and second conductors being constructed and arranged to operate as a capacitively loaded dipole antenna in the AM band and a resonant antenna in the FM band.

Claim 6

A broadband radio antenna for a vehicle-mounted receiver comprising in combination: a windshield aperture in the vehicle defined by a metallic body element, a laminated windshield of known dielectric constant disposed within the aperture, first and second conductors disposed between the laminates of the windshield, and having transverse portions adjacent but spaced from the body element bounding the upper periphery of the windshield and longitudinal portions extending in spaced parallel fashion along the centerline of the windshield, an antenna lead comprising coaxial center and outer conductors for connecting the first and second conductors to a radio receiver, means adjacent the bottom periphery of the windshield for electrically connecting the longitudinal portions of the first and second conductors to the center conductor, means connecting the body element to the outer conductor, the first and second conductors being constructed and arranged to operate as a capacitively loaded dipole antenna in the AM band and a resonant antenna in the FM band.

Claim 7

A broadband radio antenna as defined in claim 3 wherein the transverse portions are of effectively dissimilar length to resonate the antenna at spaced frequencies in the FM band.

Claim 8

An AM-FM antenna for vehicular radio receivers comprising in combination: a windshield aperture defined by a metallic vehicle body element, a laminated windshield of known dielectric constant diaposed within the aperture, first and second L-shaped fine wire conductors disposed between the laminates of the windshield in reversely symmetrical relation, each of the conductors having a transverse portion adjacent but spaced from the body element bounding the top periphery of the windshield, and a longitudinal portion extending in spaced parallel fashion along the centerline of the windshield to points adjacent the bottom periphery thereof, an antenna lead comprising coaxial center and outer conductors for connecting the first and second conductors to a radio receiver, means connecting the first and second conductors to the center conductor at said points, and means connecting the body element to the outer conductor, the first and second conductors being constructed and arranged such that in the AM band the transverse portions operate as capacitors loading the longitudinal portions, and in the FM band the transverse portions operate as a transmission line with the adjacent body element to resonate the conductors.

Claim 9

An AM-FM antenna for vehicular radio receivers comprising in combination: a windshield aperture defined by a metallic vehicle body element, a laminated windshield of known dielectric constant diaposed within the aperture, first and second L-shaped fine wire conductors disposed between the laminates of the windshield in reversely symmetrical relation, each of the conductors having a transverse portion adjacent but spaced from the body element bounding the top periphery of the windshield, and a longitudinal portion extending in spaced parallel fashion along the centerline of the windshield to points adjacent the bottom periphery thereof, an antenna lead comprising coaxial center and outer conductors for connecting the first and second conductors to a radio receiver, means connecting the first and second conductors to the center conductor at said points, and means connecting the body element to the outer conductor, the first and second conductors being constructed and arranged such that in the AM band the transverse portions operate as capacitors loading the longitudinal portions, and in the FM band the transverse portions operate as a transmission line with the adjacent body element to resonate the conductors.

Claim 10

A broadband radio antenna as defined in claim 5 wherein the transverse portions are of dissimilar length to resonate the first and second conductors at spaced frequencies in the FM band.