Narrowband/wideband dual mode antenna

• US 6,384,792 B2
• Filed: 06/14/2001
• Issued: 05/07/2002
• Est. Priority Date: 06/14/2000
• Status: Active Grant

• Current Assignee: R.A. Miller Industries, Inc.
• Original Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Inventors: Apostolos, John T.
• Primary Examiner(s): LE, HOANGANH T
• Application Number:
  US09/882,783
• Publication Number:
  US 20020011955A1
• Time in Patent Office: 327 Days
• Field of Search: H01/Q 1.114, 343/744, 343/895, 343/745, 343/846, 343/741, 343/742, 343/748, 343/700.MS
• US Class Current: 343/744
• CPC Class Codes: H01Q 1/242 specially adapted for hand-held use
• CPC Class Codes: H01Q 1/243 with built-in 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 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 9/28 Conical, cylindrical, cage, strip, gauze, or like elements having an extended radiating surface; Elements comprising two conical surfaces having collinear axes and adjacent apices and fed by two-conductor transmission lines waveguide horns or mouths H01Q13/00; slot antennas H01Q13/00
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407

Abstract

The present invention features a dual mode, meander line loaded antenna (MLA) having an additional wideband plate or hat located above the horizontal top surface of the MLA antenna. The upper plate is spaced a predetermined distance above the MLA and held in place by dielectric blocks of a predetermined thickness. By properly spacing the additional plate, simultaneous wideband and narrowband reception can be performed. The added upper plate generally does not interfere with the usual narrowband operation of the original antenna structure. The modified antenna can accept radio frequency signals across a wide range of frequencies. The additional upper plate can be retrofitted to existing MLAs to modify them for dual mode operation.

Claims

1. A narrowband/wideband dual mode antenna comprising:

a) meander line loaded antenna (MLA) comprising;

a pair of vertical sections disposed substantially perpendicular to a ground plane, one of said pair of vertical sections being electrically connected to said ground plane;

a substantially horizontal top section disposed above and substantially perpendicular to said pair of vertical sections, each end of said top section being proximate one of said pair of vertical sections and separated therefrom by a gap;

one or more meander line elements proximate at least one of said gaps and operatively connected to one of said vertical sections and to said top section;

b) a wideband plate disposed a predetermined distance above and electrically isolated from said horizontal top section; and

c) a feed means for accepting a voltage induced between said wideband plate and said top section by an incoming signal.

2. The narrowband/wideband dual mode antenna according to claim 1, wherein said feed means is a high impedance amplifier.

3. The narrowband/wideband dual mode antenna according to claim 2, wherein said high impedance amplifier is a field effect transistor (FET) having a gate, a drain, and a source, wherein said gate is connected to said wideband plate, said source is connected to said top section, and said drain is connected to said vertical section electrically connected to said ground plane.

4. The narrowband/wideband dual mode antenna according to claim 1, wherein said electrical isolation between said wideband plate and said horizontal top section is provided by a dielectric material disposed therebetween.

5. The narrowband/wideband dual mode antenna according to claim 4, wherein said dielectric material is selected from the group:

polytetrafluoroethylene, polyethylene, and phenolic.

6. The narrowband/wideband dual mode antenna according to claim 1, wherein said meander line loaded antenna is a tunable, varied impedance transmission line.

7. The narrowband/wideband dual mode antenna according to claim 6, wherein said tunable, varied impedance transmission line comprises switching means for selectively connecting and disconnecting at least a portion of said transmission line for tuning a narrowband signal.

8. The narrowband/wideband dual mode antenna according to claim 1, wherein said dual mode antenna simultaneously operates with a wideband signal and a narrowband signal.

9. The narrowband/wideband dual mode antenna according to claim 1, wherein said meander line loaded antenna is a printed circuit structure.

10. The narrowband/wideband dual mode antenna according to claim 4, wherein said dielectric material is at least one dielectric bar disposed between at least two of the structures:

said ground plane, at least one of said pair of vertical sections; and

said substantially horizontal top section.

11. The narrowband/wideband dual mode antenna according to claim 1 wherein said meander line elements are electrically isolated from said horizontal top section by a dielectric material.

12. The narrowband/wideband dual mode antenna according to claim 10, further comprising fastening means for securing said at least one dielectric bar to one of said at least two structures.

13. The narrowband/wideband dual mode antenna according to claim 12, wherein said fastening means comprises at least one from the group of:

screw, bolt, and adhesive.

14. A method for operating dual bandwidths using a meander line loaded antenna (MLA), comprising the steps of:

a) providing an MLA comprising;

a pair of vertical sections disposed substantially perpendicular to a ground plane, one of said pair of vertical sections being electrically connected to said ground plane;

a substantially horizontal top section disposed above and substantially perpendicular to said pair of vertical sections, each end of said top section being proximate one of said pair of vertical sections and separated therefrom by a gap;

one or more meander lines proximate at least one of said gaps and operatively connected to at least one of said vertical sections and to said top section;

b) disposing a wideband plate at a predetermined distance above and electrically isolated from said horizontal top section by at least one dielectric block;

c) securing said wideband plate to said at least one dielectric block; and

d) providing a feed means electrically connected to said horizontal top section and said wideband plate for accepting a voltage induced between said wideband hat and said horizontal top section by an incoming signal, whereby said dual mode antenna receives simultaneous broadband and narrowband signals.

15. The method for operating dual bandwidths according to claim 14, further comprising the step of electrically connecting said vertical section to said feed means, wherein said connecting does not cross said gap.

16. The method for operating dual bandwidths according to claim 14, wherein said dielectric block comprises at least one high-frequency dielectric material from the group:

polytetrafluoroethylene, polyethylene, and phenolic.

17. The method for operating dual bandwidths according to claim 14, wherein said meander line is a tunable, varied impedance transmission line.

18. The method for operating dual bandwidths according to claim 17, wherein said tunable, varied impedance transmission line comprises switching means for selectively connecting and disconnecting at least a portion of said variable impedance transmission line from the remaining portion thereof, thereby tuning said narrowband signals.

19. The method for operating dual bandwidths according to claim 14, wherein said meander line loaded antenna is manufactured by printed circuit techniques.