Communications: radio wave antennas – Antennas – With vehicle
Reexamination Certificate
1999-11-29
2001-09-04
Ho, Tan (Department: 2821)
Communications: radio wave antennas
Antennas
With vehicle
C343S860000, C343S872000
Reexamination Certificate
active
06285331
ABSTRACT:
FIELD OF THE INVENTION
This invention concerns improvements in and relating to antennas for use in providing radio communication to and/or from motor vehicles, more especially in the higher frequency wavebands employed by mobile telephones or like equipment.
BACKGROUND
Recently there has become known a radio antenna of this type that is referred to as an “on glass or glass-mount” antenna. Such antennas comprise a radiating element that is mounted externally on a glass window or windscreen of the vehicle and an internal connector that is coupled to radio apparatus within the vehicle and is coupled to the external antenna by a capacitor plate mounted to the internal surface of the windscreen and cooperating with an external capacitor plate electrically coupled to the external antenna. The overlapping internal and external capacitor plates together with the dielectric material of the glass form a capacitor that couples the internal connector to the external antenna and may form part of a matching circuit that also serves to match the impedance of the antenna to the radio apparatus. An example of an internal connector utilising this arrangement is described in European Patent No. 0456350.
The external antenna in such an arrangement is, apart from the coupling capacitor, of conventional form and comprises the normal rod or whip-like conductor that has a length corresponding to a fraction of the working wavelength and is loaded by an inductance that is usually incorporated in the whip to provide base or centre loading of the antenna.
Whilst an external antenna of this kind is functionally effective, in the context of a motor vehicle it has the severe disadvantage that it is vulnerable to vandalism when the vehicle is unattended.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to address this problem.
The invention provides an “on glass or glass-mount” antenna for a motor vehicle having a mounting base incorporating a capacitor plate arranged to be secured to the surface of a window or screen of the vehicle, characterised in that the radiating clement of the antenna is located in substantially the sane plane as the capacitor plate.
Preferably, the radiating element and capacitor plate are enclosed by a protective dielectric cover conforming closely to the glass surface,
The arrangement according to the invention is based upon the surprising observation that an antenna of appropriate configuration can be arranged to lie flush with the glass surface forming the dielectric of the coupling capacitor, and can operate effectively without the need for the conventional whip that in known designs has extended away from the glass, to form a target for vandals. The arrangement further provides a reduction in wind noise, and resistance to damage in car washes.
The antenna may be formed in any desired manner, and could be comprised of elements of electrically conductive material such as, for example, metal embedded in the dielectric cover. Preferably however the antenna is formed by conductive tracks of a printed circuit board. The circuit board may itself embody the dielectric cover, but preferably the board is arranged to fit within a separate cover of synthetic plastics material that is moulded to an aesthetically pleasing shape whilst having a profile that conforms closely to the glass surface and can be secured thereto by a suitable adhesive,
REFERENCES:
patent: 4163195 (1979-07-01), Sauer
patent: 4931805 (1990-06-01), Fisher
patent: 4992800 (1991-02-01), Parfitt
patent: 5005019 (1991-04-01), Zaghloul et al.
patent: 5212492 (1993-05-01), Jesman et al.
patent: 5235736 (1993-08-01), Hahs, Jr. et al.
patent: 5278572 (1994-01-01), Harada et al.
patent: 5422649 (1995-06-01), Huang
patent: 5457470 (1995-10-01), Hai et al.
patent: 5565877 (1996-10-01), Du et al.
patent: 5742255 (1998-04-01), Afendras
patent: 0 456 350 (1991-11-01), None
Jesman Andrew
Jesman Christopher
Ho Tan
Jacobson & Holman PLLC
LandOfFree
Antenna more especially for motor vehicles does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Antenna more especially for motor vehicles, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Antenna more especially for motor vehicles will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2498956