Communications: radio wave antennas – Antennas – Plural separate diverse type
Reexamination Certificate
2000-04-14
2001-12-11
Wong, Don (Department: 2821)
Communications: radio wave antennas
Antennas
Plural separate diverse type
C343S797000, C343S895000
Reexamination Certificate
active
06329954
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to antenna systems, and more particularly to dual-antenna systems.
A variety of dual-transmitter broadcasting formats are under development. Such formats include simultaneous transmission of signals from both satellite transmitters and terrestrial (or land-based) transmitters. Two of such formats those identified by the trademark SIRIUS RADIO and the trademark XM RADIO. Both formats have published transmission specifications. The satellite transmissions cover the vast majority of the geographic broadcast area. The terrestrial transmissions complement the satellite coverage primarily in urban areas where the satellites may be blocked from a receiver by a building.
New antennas for receiving the dual-transmission signals are required, especially for automotive applications. The antennas (e.g. whips and window grids) typically used in the automotive area adequately receive signals from terrestrial transmitters. However, the radiation patterns of monopoles have their best reception at low elevation angles with nulls at the zenith. Therefore, monopoles are incapable of receiving signals from satellite transmitters.
SUMMARY OF THE INVENTION
The aforementioned problems are overcome in the present invention wherein a dual-antenna system, appropriate for automotive applications, is capable of receiving both satellite transmission signals and terrestrial transmission signals. The system includes a first antenna for receiving satellite transmissions and a second antenna for receiving terrestrial transmissions. The terrestrial antenna is one or more antenna elements arranged either concentrically with, or in a symmetrical configuration with respect to, the satellite antenna.
In a preferred embodiment, the satellite antenna is a cross dipole, and the terrestrial antenna is a plurality of monopoles arranged symmetrically about the cross dipole. In an alternative embodiment, the satellite antenna is a quadrifilar helix, and the terrestrial antenna is a monopole or sleeve dipole positioned concentrically within the helix. In another alternative embodiment, the system includes a helix and a plurality of monopoles arranged symmetrically about the helix.
In the disclosed embodiment, the satellite elements are packaged and housed within a relatively low profile, aesthetically pleasing housing for mounting on a vehicle body panel, such as the roof.
The present invention is capable of receiving both satellite transmissions and terrestrial transmissions. The antenna system can be tuned to meet the SIRIUS RADIO format or the XM RADIO format, and can be scaled to other frequencies. The antenna therefore provides operability heretofore unavailable in an antenna system, particularly in the automotive field.
These and other objects, advantages, and features of the invention will be more readily understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings.
REFERENCES:
patent: 4218685 (1980-08-01), Ellis, Jr.
patent: 4466003 (1984-08-01), Royce
patent: 4730195 (1988-03-01), Phillips et al.
patent: 5264862 (1993-11-01), Kumpfbeck
patent: 5317327 (1994-05-01), Piole
patent: 5440317 (1995-08-01), Jalloul et al.
patent: 5600341 (1997-02-01), Thill et al.
patent: 5923305 (1999-07-01), Sadler et al.
patent: 6160512 (2000-12-01), Desclos et al.
patent: 19933723 (2000-01-01), None
patent: 0957533 (1999-11-01), None
patent: 2339969 (2000-02-01), None
patent: 4134906 (1992-05-01), None
patent: 6334436 (1994-12-01), None
patent: WO 0059070 (2000-10-01), None
Fuchs Andreas Dirk
Marino Ronald Andrew
Nguyen Hoang
RecepTec L.L.C.
Warner & Norcross & Judd LLP
Wong Don
LandOfFree
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