Nippon Sheet Glass Company, Limited

Sumitomo Chemical Company, Limited

Yuji Baba

Harunori Murakami

Nobuya Niizaki

Kanta Urakami

Hirofumi Natsume

Masato Arisawa

Hiroshi Iijima

Masaru Maeda

Tatsumi Tokuda

A glass antenna device having an AM and FM antennas provided on a rear window glass panel on which a defogger is formed is provided, the sensitivity and directivity of the device being improved. The device comprises a defogger provided on a rear window glass panel of the motor vehicle, an AM antenna provided in a space other than the defogger on the rear window glass panel, an FM antenna provided in a space between the defogger and the AM antenna on the rear window glass panel, a two-input amplifier for amplifying signals received by the AM and FM antennas, an AM lead wire for connecting between a feeding terminal of the AM antenna and the amplifier, an FM lead wire for connecting between a feeding terminal of the FM antenna and the amplifier, and an inductor inserted in the AM lead wire near to the AM feeding terminal.

Antenna device for motor vehicle

A glass antenna system for an automobile comprises a T-shaped or pi-shaped dynamic impedance matching circuit. Another system comprises an integrated circuit consisting of T-shaped FM and AM matching circuits each connected to a common cable. The T-shaped or pi-shaped matching circuit comprises at least two varactor diodes each applied to a channel selection voltage to match the FM antenna impedance with that of the FM receiver including that of the transmission cable.

Glass antenna system for automobile

Glass antenna system for automobiles

A glass antenna for an automobile uses a coil connected directly to a bus for defogging heaters as an FM subsidiary antenna and a T-shaped impedance matching circuit to provide a monotone change of impedance within the FM frequency band. A reverse T-shaped FM main antenna is employed in conjunction with the FM subsidiary antenna to provide a diversity system to enhance receiving sensitivity in entire directions. The T-shaped matching circuit comprises at least two varactor diodes each applied to a channel selection voltage to match the FM antenna impedance with that of the FM receiver including that of the transmission cable.

Glass antenna for automobile

A window glass antenna device is combined with a laminated window glass panel, such as a rear window glass panel of an automobile, which has a pair of inner and outer glass layers bonded to each other. The window glass antenna device has, as antenna elements, a plurality of defroster heater wires disposed between the glass layers. A pair of spaced first and second bus bars is disposed between the glass layers, the first bus bar electrically interconnecting first ends of the defroster heater wires and the second bus bar electrically interconnecting second ends of the defroster heater wires. A first electrode is disposed on an outer surface of the inner glass layer and joined to the second bus bar for supplying electric energy to heat the defroster heater wires, and a second electrode is disposed on the outer surface of the inner glass layer in confronting relationship to the first bus bar. The first bus bar and the second electrode jointly provide a capacitor for supplying a radio signal received by the defroster heater wires.

Window glass antenna device

A first inductance element is series-connected into a reception signal path of an antenna circuit between an antenna element and a receiver. A second inductance element is arranged to connect the antenna circuit to ground. These inductance elements series- and parallel-resonate with a ground stray capacitance of the antenna circuit including a feeder cable, so that reduction of gain of the reception system due to the stray capacitance is improved. A damping resistor is coupled to the second inductance element. The system has high reception sensitivity over a wide reception range with eliminating use of a pre-amplifier.

Growing community of inventors

Doshomachi, Japan

Yuji Baba