Glass antenna system for automobile
AssigneesSumitomo Chemical Company, Limited, Nippon Sheet Glass Co., Ltd.
InventorsKanta Urakami, Nobuya Niizaki, Hirofumi Natsume, Masato Arisawa, Harunori Murakami, Yuji Baba
Life of this patent
Estimating the term…
Abstract
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.
Claims2
A glass antenna system for an automobile comprising:
- two main matching circuits each connected to an antenna provided on a window glass of the automobile, each of said main matching circuits including a first coil and a first varactor diode connected thereto, to provide first resonance circuits, and
- two auxiliary matching circuits each connected to one of said main matching circuits through a common node, each of said auxiliary matching circuits including a second coil and a second varactor diode connected thereto, to provide second resonance circuits;
- a capacitor connected between two of said common node;
- a transmission cable operatively connected to said auxiliary matching circuits through an output terminal;
- and
- resistors each connected to said output terminal and each applying a voltage to said second varactor diode through said second coil.
A glass antenna system for an automobile comprising:
- a main matching circuit connected to an antenna provided on a window glass of the automobile, said main matching circuit including a first coil and a first pair of cathode-common varactor diodes connected thereto, to provide first resonance circuits;
- and
- an auxiliary matching circuit connected to said main matching circuit through a common node, said auxiliary matching circuit including a second coil and a second pair of varactor diodes having a common cathode connected thereto, to provide second resonance circuits;
- a capacitor connected between said common node and ground;
- a transmission cable operatively connected to said auxiliary matching circuit through an output terminal;
- and
- resistors each connected between said output terminal and said common cathode.
Dependencies are inferred from the claim text.