Antenna for a plurality of radio services

• US 6,218,997 B1
• Filed: 04/19/1999
• Issued: 04/17/2001
• Est. Priority Date: 04/20/1998
• Status: Active Grant

• Current Assignee: Delphi Delco Electronics Europe GmbH (Aptiv PLC)
• Original Assignee: FUBA Automotive GmbH
• Inventors: Hopf, Jochen, Lindenmeier, Heinz
• Primary Examiner(s): PHAN, THO GIA
• Application Number:
  US09/294,615
• Time in Patent Office: 729 Days
• Field of Search: H01/Q.100, H01/Q 2.100, 343/704, 343/713, 343/767, 343/770, 343/752, 343/725, 343/726, 343/727, 343/729, 343/730, 343/700.MS, 343/702, 343/829, 343/849, 343/848, 343/852
• US Class Current: 343/725
• CPC Class Codes: H01Q 1/3275 mounted on a horizontal surface of the vehicle, e.g. on roof, hood, trunk
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 21/30 Combinations of separate antenna units operating in different wavebands and connected to a common feeder system
• CPC Class Codes: H01Q 5/40 Imbricated or interleaved structures; Combined or electromagnetically coupled arrangements, e.g. comprising two or more non-connected fed radiating elements
• CPC Class Codes: H01Q 9/0442 with particular tuning means

Abstract

The invention relates to a mobile antenna for a plurality of radio services in the form of a dipole or monopole, with an antenna conductor and with at least one flatly designed roof capacity disposed substantially vertical relative to the antenna conductor for a first radio service with polarization disposed vertically relative to the roof capacity. The roof capacity is designed in the form of a conductive board or a thin conductive layer. In order to create an antenna function for at least one additional radio service with polarization oriented parallel with the roof capacitance, at least one slot is incorporated in the conductive board or layer with the slot length selected to form a suitable impedance bandwidth. In order to decouple signals of an additional radio service, first and second connection points are formed on the edges of the slot, wherein the connecting points oppose each other.

Claims

1. A multiband-antenna for receiving a first radio service and at least one additional radio service, the multiband-antenna in the form of a monopole, comprising:

a conductive board comprising a thin conductive layer serving as a roof capacitance said conductive board having at least one slot having a slot length sufficient for forming a resonance in the frequency range of the at least one additional radio service, and a slot width for forming a suitable impedance bandwidth;

an antenna conductor disposed substantially perpendicular to said conductive board and for receiving the first radio service with vertically oriented polarization relative to the conductive board; and

a first and a second connection point, respectively formed on the edges of said slot at points opposing each other for forming a horizontally polarized antenna for decoupling the signals of the at least one additional radio service.

2. The antenna, as recited in claim 1, further comprising a non-symmetrical electrical line having an inner conductor coupled to said first connection point, and having its ground conductor coupled to said second connection point, said non-symmetrical line being installed without electrically effective spacing, parallel with the conductive board forming the roof capacity, and also parallel with the surface of the antenna conductor.

3. The antenna according to claim 2, wherein said antenna conductor is designed flatly conductive and wherein said roof conductive board has a first edge and a second edge said antenna conductor conductively connected with the first edge to the roof capacitance, and conductively connected with the second edge to a conductive base surface

an additional coupling conductor being disposed vertically relative to the conductive base surface and roof capacity and connected to a third connection point for the first radio service being formed between the conductive base surface and the end of the additional, vertically disposed coupling conductor facing said base surface.

4. The antenna according to claim 3, wherein the roof capacity and the flatly designed antenna conductor are designed as printed circuit or pc boards conductively coated on both sides, the conductive surface present on one side of the pc boards in each case forming the conductive surface;

and wherein the non-symmetrical line is designed in the form of a strip line, whereby the strip line is printed on the opposite side of the conductive surface and the surface forms a ground conductor of the strip line.

5. The antenna according to claim 3, wherein creating an antenna function for an additional first radio service with a higher frequency and with polarization vertically oriented relative to the conductive base surface, slots are incorporated in the roof capacity.

6. The antenna according to claims 1, wherein a conductive base surface is disposed horizontally and the monopole antenna for the frequency band of a terrestrial telephone radio service with vertical polarization is tuned to said frequency band of said telephone radio service as the first radio service, and tuned or adapted to a satellite radio service with waves substantially incident with horizontal polarization, as the additional radio service.

7. The antenna according to claim 1, wherein the roof capacity and the antenna conductor disposed vertically relative to said roof capacity are dimensioned so that resonance exists in the first radio service (GSM frequency range), and that the length and width of said slot are dimensioned that its resonance is suitable for receiving the additional radio service (GPS).

8. The antenna according to claim 1, comprising a 90°

hybrid circuit, and said slot comprises two slots each having two connection points and a non symmetrical line connected thereto for a further radio service with circular polarization, wherein the two lines are installed leading to the two inputs of said 90°

hybrid circuit, the antenna connection point for the further radio service being formed on the output of said hybrid, and wherein the slots in the conductive board of the roof capacity are disposed relative to one another at an angle of almost 90°

so that the reception of the circularly polarized waves is optimized with a preset rotational direction.

9. The antenna according to claim 8, comprising a frequency bandpass filter mounted in the further antenna connection point for passage of the signals for the further radio service, and a low-noise amplifier mounted on a conductive base surface of the antenna.

10. The antenna according to claim 1, wherein said antenna conductor is designed as a three-dimensional element and a non symmetrical line is installed either in the field-free interior of said antenna conductor or electrically ineffectively parallel with the outer surface of said antenna conductor and with a conductive base surface, and further comprising:

a frequency separation filter disposed on the conductive base surface, into which the non symmetrical line is inserted and to which the antenna conductor is connected, and on which either separated antenna connection points for all radio services are present.