Advanced multilevel antenna for motor vehicles

• US 20030112190A1
• Filed: 10/17/2002
• Published: 06/19/2003
• Est. Priority Date: 04/19/2000
• Status: Active Grant

• Current Assignee: Advanced Automotive Antennas, S.L. (Panasonic Holdings Corporation)
• Original Assignee: Advanced Automotive Antennas, S.L. (Panasonic Holdings Corporation)
• Inventors: Baliarda, Carles Puente, Rozan, Edouard-Jean-Louis
• Granted Patent: US 6,809,692 B2
• Time in Patent Office: Days
• US Class Current: 343/713
• CPC Class Codes: H01Q 1/1271 for mounting on windscreens
• CPC Class Codes: H01Q 1/325 characterised by the location of the antenna on the vehicle
• CPC Class Codes: H01Q 1/3283 side-mounted antennas, e.g. bumper-mounted, door-mounted mounted on windscreens H01Q1/1271
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 11/14 with parts bent, folded, shaped or screened or with phasing impedances, to obtain desired phase relation of radiation from selected sections of the antenna or to obtain desired polarisation effect H01Q11/20 takes precedence

Abstract

The invention relates to an antenna for a motor vehicle, having the following parts and characteristics: a) a transparent window covered with a transparent, optically conductive plate on at least one side of any of the window material plates; b) a multilevel structure printed on said conductive plate. Said multilevel structure consists of a set of polygonal elements pertaining to one same class, preferably triangles or squares; c) a transmission line powering two conductors; d) a similar impedance in the power supply point and a horizontal radiation diagram in at least three frequencies within three bands. The main advantage of the invention lies in the multiband and multiservice performance of the antenna. This enables convenient and easy connection of a simple antenna for most communication systems of the vehicle.

Claims

1. An antenna for a motor vehicle comprising:

a) a transparent window coated with an optically transparent conducting layer in at least one side of the layers composing the transparent window,

b) at least a multilevel structure supported by said conducting layer, being said multilevel structure composed by a set of polygonal elements of the same class (the same number of sides), preferably triangles or squares, being such polygonal elements electromagnetically coupled either by means of an ohmic contact or a capacitive or inductive coupling mechanism, wherein the contact region between at least the 75% of said polygonal elements is always longer than 5% and shorter than a 50% of the perimeters of said polygonal structures.

c) A two-conductor feeding transmission line, wherein at least one of the conductors of said transmission line is coupled to the inner conducting layer enclosed in one of the polygonal elements composing said multilevel structure, by means of either an ohmic contact or a capacitive or inductive coupling mechanism.

and wherein the antenna features a similar impedance at the feeding poing and a similar horizontal radiation pattern in at least three bands, wherein at least two of said three frequencies are selected from the following;

FM (80 MHz˜

110 MHz), DAB (205 MHz˜

230 MHz), Tetra (350 MHz˜

450 MHz), DVB (470 MHz˜

862 MHz), GSM900/AMPS (820 MHz˜

970 MHz), GSM1800/DCS/PCS/DECT (1700 MHz˜

1950 MHz), UMTS (1920 MHz˜

2200 MHz ), Bluetooth (2500 MHz) and WLAN (4.5 GHz˜

6 GHz) such that said antenna can be operated simultaneously at any of the telecommunication services within said bands.

2. An antenna for a motor vehicle as claimed in claim 1, wherein the characteristic multilevel structure is a solid-shape structure with the transparent conducting layer filling the inside area of the polygonal elements of said multilevel structure, and wherein the rest of the window surface is not coated with said conducting layer.

3. An antenna for a motor vehicle as claimed in claim 1, wherein the transparent conducting layer only defines a grid composed by the perimeter of the polygonal elements of the characteristic multilevel structure, and wherein the rest of the window surface is not coated with said conducting layer.

4. An antenna for a motor vehicle as claimed in claim 1, wherein the transparent conducting layer covers most of the transparent window support except a solid multilevel structure impressed on said transparent conducting layer, and wherein the border of the window can optionally remain uncoated.

5. An antenna for a motor vehicle as claimed in claim 1, wherein the perimeter of the polygonal of the polygonal elements of said multilevel structure define a slot antenna impressed on said transparent conducting layer, wherein said transparent conducting layer can be optionally used to protect the inside-vehicle from heating by the incoming infrared radiation.

6. An antenna for a motor vehicle as claimed in claim 1, wherein a first surface of the transparent support of the window is coated with a transparent conducting layer except a solid multilevel structure impressed on said transparent conducting layer as claimed in claim 4, wherein a second parallel surface of the transparent support of the window is coated with the complementary structure of said multilevel structure, in such a way that the uncoated shape in said first surface becomes coated in second surface, and the coated shape in said first surface becomes uncoated in said parallel second surface, wherein said first and second surface can be any of the surfaces of a multi-layer window structure, and wherein said transparent conducting layer layered on first and second surface can be optionally used to protect the vehicle inside from the incoming heating infrared radiation.

7. A set of at least two antennas impressed on at least a motor vehicle window according to claim 1, 2, 3, 4, 5, or 6 wherein said antennas are used for space or polarization diversity or a combination of both diversity mechanism for at least one of the telecommunication services operating within the antenna.

8. An antenna for a motor vehicle as claimed in claim 1, 2, 3, 4, 5, 6 or 7 wherein the multilevel structure approximates an ideal Sierpinski triangle with at least three scale levels, being the several scale levels of the structure tuned at least three frequencies within three bands selected from the following:

FM (80 MHz˜

110 MHz), DAB (205 MHz˜

230 MHz), Tetra (350 MHz˜

450 MHz), DVB (470 MHz˜

862 MHz), GSM900/AMPS (820 MHz˜

970 MHz), GSM1800/DCS/PCS/DECT/(1700 MHz˜

1950 MHz), UMTS (1950 MHz˜

2200 MHz ), Bluetooth (2500 MHz) and WLAN (4.5 GHz˜

6 GHz) such that said antenna can be operated simultaneously at any of the telecommunication services within said bands.

9. An antenna for a motor vehicle as claimed in claim 8, wherein the multilevel structure contains at least six scale-levels tuned to operate at least at the six following bands:

FM (80 MHz˜

110 MHz), DAB (205 MHz˜

230 MHz), Tetra (350 MHz˜

450 MHz) GSM900/AMPS (820 MHz˜

970 MHz), GSM1800/DCS/PCS/DECT (1700 MHz˜

1950 MHz) Bluetooth (2500 MHz) and UMTS (1950 MHz˜

2200 MHz)

10. An antenna for a motor vehicle as claimed in claims 1, 2, 3, 4, 5, 6, 7, 8, or 9 wherein the multilevel structure is loaded with a reactive structure impressed on the same transparent conducting layer as the multilevel structure.

11. An antenna for a motor vehicle as claimed in claims 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wherein said conductive and transparent material is either ZnO, ITO, SnO₂ or any combination of them.

12. An antenna for a motor vehicle as claimed in claim 1, wherein the conducting layer only defines a grid composed by the perimeter of the polygonal elements of the characteristic multilevel structure, and wherein said external perimeter wire is used as heating defrosting structure.

13. An antenna for a motor vehicle as claimed in claims 1, 2, 3, 4, 5, or 6 wherein the antenna includes a multilevel structure composed by squared elements, wherein said geometry is used to obtain polarization diversity within the same antenna by feeding said antenna with at least two ports, being said ports defined by two conductors, and wherein half of the ports are located in a point of the symmetry axis of the structure and the outer half of the ports are located in a point of the other orthogonal symmetry axis.