Multi-band vehicular blade antenna

• US 20040036659A1
• Filed: 06/18/2003
• Published: 02/26/2004
• Est. Priority Date: 06/19/2002
• Status: Active Grant

• Current Assignee: Harada Industry Company Limited
• Original Assignee: Harada Industry Company Limited
• Inventors: Langley, Richard Jonathan, Walbeoff, Tony
• Granted Patent: US 6,873,296 B2
• Time in Patent Office: Days
• US Class Current: 343/713
• CPC Class Codes: H01Q 1/283 Blade, stub antennas
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• 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 5/328 between a radiating element and ground
• CPC Class Codes: H01Q 5/371 Branching current paths

Abstract

A multi-band blade antenna for use on a vehicle is formed by patterning the metal on both sides of a printed circuit board. One side is patterned into low-frequency patch and ground elements, and the other side is patterned into high-frequency patch and ground elements. The length of the patterned patch element on the low-frequency side of the board approximates the length of the board, while the effective length of the high-frequency patch element is approximately twice as long. Tuning for the frequency bands of mobile telephones in different regions (for instance, the European Union, United States and Japan) is by means of differences in slot length in the patch member on the low-frequency side, and differences in separation between the patch and ground members on the high-frequency side. RLC components are affixed to the low-frequency side after patterning. The printed circuit board has a shape which, in a complementary housing, may add ornamentation to the exterior of a vehicle on which it is mounted.

Claims

1. A multi-band vehicular blade antenna, comprising a generally-planar dielectric member adapted to be attached so as to form part of a vehicle and having respective metallic overlays on its two opposite faces, the two overlays being adapted to be connected, proximate one end of the antenna, to a vehicular grounding connection when the antenna is in an operative position on the vehicle, each overlay being associated with a respective operative frequency band of the antenna.

2. A multi-band antenna as in claim 1, wherein each overlay is configured to extend from the one end of the antenna toward the other end of the antenna through a respective characteristic length that at least partially defines the respective operative frequency band of the antenna.

3. A multi-band antenna as in claim 2, wherein the characteristic length of one of the overlays, adapted to be used for reception/transmission of a first frequency band lower than a second frequency band associated with the other overlay, approximates the length of the antenna between the one end and the other end of the antenna.

4. A multi-band antenna as in claim 3, wherein the other overlay has a characteristic length approximating to double the length of the antenna, at least a portion of the other overlay having a snaking configuration with reversing sections.

5. A multi-band antenna as in claim 4, wherein each of the reversing sections extends generally normal to the lengthwise direction of the antenna.

6. A multi-band-antenna as in claim 3, wherein the one overlay has a series of grooves formed in its one end, that end corresponding to the one end of the antenna, each of the grooves extending generally parallel to a lengthwise direction of the antenna and having dimensions that partially define the first frequency band.

7. A multi-band antenna as in claim 6, wherein the one overlay has two grooves.

8. A multi-band antenna as in claim 6, wherein that face of the dielectric member on which the one overlay sits also has a ground overlay proximate the one end of the antenna, the separation distance between the one overlay and the ground overlay partially defining the first frequency band.

9. A multi-band antenna as in claim 8, wherein the one overlay and the ground overlay are connected by means of a set of electrical components which together partially define the first frequency band.

10. A multi-band antenna as in claim 9, wherein the set of electrical components comprises a resistive element in parallel with a second element comprising a serially-connected capacitive element and inductive element, the resistive element connecting the ground overlay to the one overlay on one side of a first one of the grooves, and the second element connecting the ground overlay to the one overlay on the other side of the first one of the grooves.

11. A multi-band antenna as in claim 6, wherein that face of the dielectric member on which the other overlay sits also has another ground overlay proximate the one end of the antenna, the separation distance between the other overlay and the another ground overlay partially defining the second frequency band.

12. A multi-band antenna as in claim 1, wherein the antenna is adapted to be mounted on an outside surface of a vehicle so as to extend outwardly from that surface, and wherein the grounding connection is to the outside surface of the vehicle.

13. A multi-band-antenna as in claim 1, wherein the dielectric member and the metallic overlays are formed as a printed circuit board.

14. A multi-band antenna as in claim 13, wherein the two overlays are adapted to be connected to each other proximate the one end of the antenna by means of a via-hole extending through the dielectric member.

15. A multi-band antenna as in claim 1, wherein the antenna has a generally rectangular contour.

16. A multi-band antenna as in claim 1, wherein the antenna has a raked contour in which at least a portion of each side extends at an angle that is not normal to the one end of the antenna.

17. A-multi-band antenna as in claim 4, and also comprising a metallic plate soldered to the other overlay at the other end of the Antenna, the plate acting to broaden the bandwidth of the operative frequency band associated with the other overlay.

18. A multi-band antenna as in claim 17, wherein the metallic plate is configured so as to extend generally normal to the plane of the dielectric member.

19. A multi-band antenna as in claim 18, wherein the two overlays are adapted to be connected to each other proximate the one end of the antenna by means of one or more plates slots extending through the dielectric member.

20. A multi-band antenna as in claim 1, wherein one of the frequency bands is the GSM-900 Band and the other frequency band is the DCS-1800 Band.