Wide band antenna having unitary radiator/ground plane

• US 6,133,883 A
• Filed: 11/16/1999
• Issued: 10/17/2000
• Est. Priority Date: 11/17/1998
• Status: Expired due to Term

• Current Assignee: Laird Technologies Incorporated (DuPont de Nemours, Inc.)
• Original Assignee: Xertex Technologies, Inc. (Laird Limited)
• Inventors: Uspenski, Alexis, Ward, Edward Earl, Bateman, Blaine Rexel, Munson, Robert Eugene, Bancroft, Randy Cecil, Negler, Joseph Theofil
• Primary Examiner(s): Ho, Tan
• Application Number:
  US09/441,529
• Time in Patent Office: 336 Days
• Field of Search: 343/700 MS, 343/767, 343/770, 343/795, 343/828, 343/829, 343/830, 343/846, 343/848, 343/906, 200/600
• US Class Current: 343/700.0MS
• 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 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence
• CPC Class Codes: H01Q 9/0471 Non-planar, stepped or wedge-shaped patch

Abstract

An antenna is formed from a single sheet of generally planar metal that is cut to provide four geometric antenna shapes that comprise a ground plane element, a two-section shorting element that is defined by two generally parallel fold lines, a radiating element, and an arm that has one end fixed to a generally central portion of the radiating element and has a free end that extends toward a fold line. Folding the metal sheet on the two fold lines positions the radiating element above the ground plane element. A transmit/receive coaxial cable is aligned with a gap that is formed between the two sections of the shorting element. The cable'"'"'s outer metal sheath is connected to a metal tab, and the metal tab is secured to a surface of the ground plane element. The cable'"'"'s center conductor is secured to a surface of the radiating element. A radome and its mounting tab complete the antenna assembly.

Claims

1. A method of making an antenna having a ground plane element and a radiating element that physically overhangs said ground plane element, comprising the steps of:

providing a flat metal sheet;

forming said flat metal sheet to provide a ground plane element, a radiating element, and a shorting element that is physically located intermediate said ground plane element and said radiating element;

said shorting element being physically connected to said ground plane element at a first linear fold line area, and said shorting element being physically connected to said radiating element at a second linear fold line area that is generally parallel to said first linear fold line area;

forming a first pair of generally linear, side-aligned, and physically spaced through-slots in said radiating element;

said first pair of through-slots extending normal to said first and second linear fold line areas;

said first pair of through-slots defining a first soldering area on a portion of said radiating element between said first pair of through-slots;

bending said flat metal sheet on said fold line areas so as to physically position said radiating element over said ground plane element;

said radiating element and said ground plane element having a dielectric layer therebetween;

providing a first insulated cable containing a first and a second metal conductor;

soldering said first conductor to said first soldering area; and

connecting said second conductor to said ground plane element.

2. The method of claim 1 including the steps of:

forming a first U-shaped through-slot in said ground plane element, to thereby form a first metal tab in said ground plane element;

said first U-shaped through-slot having a relatively shorter dimension base portion that extends generally parallel to said fold line areas, and said first U-shaped through-slot having two parallel and relatively longer leg portions that extend generally normal to said fold line areas;

bending said first metal tab downward and away from a bottom surface of said ground plane element;

positioning said first cable adjacent to said bottom surface of said ground plane element and adjacent to said bend down first metal tab; and

bending said bend down first metal tab upward toward the bottom surface of said ground plane element, to thereby physically trap said first cable against said bottom surface of said ground plane element.

3. The method of claim 2 wherein a portion of said ground plane element is free of overhang by said radiating element, and including the steps of:

providing an device having an antenna and having a second cable extending from said device;

mounting said device on said portion of said ground plane element, such that said ground plane element provides a ground plane element for said device;

forming a second U-shaped through-slot in said ground plane element, to thereby form a second metal tab in said ground plane element;

said second U-shaped through-slot having a relatively shorter dimension base portion that extends generally parallel to said fold line areas, and said second U-shaped through-slot having two parallel and relatively longer leg portions that extend generally normal to said fold line areas;

bending said second metal tab downward and away from the bottom surface of said ground plane element;

positioning said second cable adjacent to the bottom surface of said ground plane element and adjacent to said bend down second metal tab; and

bending said bend down second metal tab upward toward the bottom surface of said ground plane element, to thereby physically trap said second cable against said bottom surface of said ground plane element.

4. The method of claim 1 including the steps of:

forming a second pair of generally linear, side-aligned, and physically spaced through-slots in said ground plane element;

said second pair of through-slots extending normal to said first and second linear fold line areas;

said second pair of through-slots defining a second soldering area on a portion of said ground plane element between said second pair of through-slots; and

soldering said second conductor to said second soldering area.

5. The method of claim 4 wherein said first cable is a coaxial cable, wherein said first conductor is a centrally located conductor at one end of said coaxial cable, and wherein said second conductor is an exposed metal sheath at said one end of said coaxial cable.

6. The method of claim 4 including the steps of:

providing said dielectric layer as an air dielectric layer;

providing said first cable as a coaxial cable having an outer metal sheath and an inner electrically insulated metal conductor;

soldering said metal sheath to said second soldering area and on a side of said ground plane element that is opposite to said radiating element;

providing a first through-hole in said ground plane element;

extending said electrically insulated metal conductor through said first through-hole and through said air dielectric layer;

providing a second though-hole in said radiating element and within said first soldering area;

extending an uninsulated end of said metal conductor through said second through-hole; and

soldering said uninsulated end of said metal conductor to a side of said radiating element that is opposite to said ground plane element.

7. The method of claim 6 wherein said step of bending said flat metal sheet physically positions said radiating element in a plane that is generally parallel to a plane occupied by said ground plane element.

8. The method of claim 6 wherein said step of bending said flat metal sheet physically positions said radiating element in a plane that is generally tilted to a plane occupied by said ground plane element.

9. The method of claim 8 wherein said plane that is occupied by said radiating element is inclined in a direction such that said shorting element defines a closest distance from said radiating element to said ground plane element.

10. The method of claim 6 including the steps of:

forming a first U-shaped through-slot in said ground plane element, to thereby form a first metal tab in said ground plane element;

said first U-shaped through-slot having a relatively shorter dimension base portion that extends generally parallel to said fold line areas, and said first U-shaped through-slot having two parallel and relatively longer leg portions that extend generally normal to said fold line areas;

bending said first metal tab downward and away from a bottom surface of said ground plane element,

bending said bend down first metal tab upward toward the bottom surface of said ground plane element to thereby form a first clip; and

positioning said coaxial cable adjacent in said first clip.

11. The method of claim 10 wherein a portion of said ground plane element is free of overhang by said radiating element, and including the steps of:

providing a GPS device having an antenna and a conductor-cable extending from said GPS device;

mounting said GPS device on said portion of said ground plane element such that said ground plane element functions as a ground plane for said GPS device;

forming a second U-shaped through-slot in said ground plane element, to thereby form a second metal tab in said ground plane element;

said second U-shaped through-slot having a relatively shorter dimension base portion that extends generally parallel to said fold line areas, and said second U-shaped through-slot having two parallel and relatively longer leg portions that extend both generally normal to said fold line areas;

bending said second metal tab downward and away from the bottom surface of said ground plane element;

bending said bend down second metal tab upward toward the bottom surface of said ground plane element to thereby form a second clip; and

positioning said conductor-cable in said second clip.

12. An antenna assembly, comprising:

a generally U-shaped, one piece, metal sheet having a generally planar ground plane element, a generally planar radiating element, and a rectangular-shaped connecting element that at least partially physically supports said radiating element in spaced relation to said ground plane element;

said connecting element meeting said ground plane element at a first linear line;

said connecting element meeting said radiating element at a second linear line that is parallel to said first linear line;

a first pair of side-aligned and parallel through-slots formed in said radiating element, said first pair of through-slots extending perpendicular to said linear lines, and a portion of said radiating element between said first pair of through-slots comprising a first soldering-area; and

a feed cable having one end that includes a first metal conductor that is connected to said ground plane element and a second metal conductor that is soldered to said first soldering-area.

13. The antenna assembly of claim 12 including:

a second pair of side-aligned and parallel through-slots formed in said ground plane element, said second pair of through-slots extending perpendicular to said linear lines, and a portion of said ground plane element between said second pair of through-slots comprising a second soldering-area;

wherein said first metal conductor that is soldered to said second soldering-area.

14. The antenna assembly of claim 13 wherein said feed cable is a coaxial cable having a center conductor soldered to said first soldering area, and having a metal sheath soldered to said second soldering area.

15. An antenna, comprising:

a generally U-shaped metal sheet having a generally planar ground plane element, a generally planar radiating element, and a rectangular-shaped connecting element that at least partially physically supports said radiating element in spaced relation to said ground plane element;

said connecting element joining said ground plane element at a first linear joining-line;

said connecting element joining said radiating element at a second linear joining-line that is parallel to said first joining-line;

a first pair of side-aligned and parallel through-slots formed in said radiating element, said first pair of through-slots extending perpendicular to said joining-lines, and a portion of said radiating element between said first pair of through-slots forming a first soldering-area;

a second pair of side-aligned and parallel through-slots formed in said ground plane element, said second pair of through-slots extending perpendicular to said joining-lines, and a portion of said ground plane element between said second pair of through-slots forming a second soldering-area;

a first through-hole formed in said ground plane element;

a second through-hole formed in said radiating element and within said first soldering-area;

a first cable;

said first cable having a first metal conductor that is soldered to said second soldering-area on a surface of said ground plane element that is opposite said radiating element; and

said first cable having a second metal conductor that extends through said first through-hole, between said ground plane element and said radiating element, through said second through-hole, and is soldered to said first soldering-area on a surface of said radiating element that is opposite said ground plane element.

16. The antenna of claim 15 including:

a first U-shaped through-slot formed in said ground plane element;

said first U-shaped slot having a base portion that extends parallel to said joining-lines, and having a pair of parallel legs that extend perpendicular to said joining-lines; and

a first metal tab formed by said first U-shaped through-slot, said first metal tab being bent to strain-relief-secure said first cable against said surface of said ground plane element that is opposite said radiating element.

17. The antenna of claim 16 wherein said radiating element is of a smaller size than said ground plane element, such that a portion of said ground plane element is free of overhang by said radiating element, the antenna including:

an antenna device mounted on said portion of said ground plane element in a manner to cause said ground plane element to provide a ground plane function for said antenna device;

a second cable connected to said antenna device;

a second U-shaped through-slot formed in said ground plane element;

said second U-shaped slot having a base portion that extends parallel to said joining-lines, and having a pair of parallel legs that extend perpendicular to said joining-lines; and

a second metal tab formed by said second U-shaped through-slot, said second metal tab being bent to physically strain-relief-secure said second cable against said surface of said ground plane element that is opposite said radiating element.

18. The antenna of claim 17 wherein said antenna device is a GPS device.

19. A patch antenna, comprising:

a generally planar and metallic ground plane in which currents flow in a given direction, said ground plane having a top surface and a bottom surface;

a generally planar and metallic radiating patch in which currents flow in said given direction, said radiating element having a top surface and a bottom surface;

said radiating patch being physically spaced vertically above said ground plane with said bottom surface of said radiating patch facing said top surface of said ground plane element;

a first pair of physically spaced and linear through-slots formed in said ground plane, said first pair of through-slots being mutually parallel and extending in said given direction of current flow, and said first pair of through-slots defining a first soldering area therebetween;

a second pair of physically spaced and linear through-slots formed in said radiating patch, said second pair of through-slots being mutually parallel and extending in said given direction of current flow, and said second pair of through-slots defining a second soldering area therebetween;

a generally linear coaxial cable having an outer located metal braid and a center located metal feed conductor, said coaxial cable extending in a direction parallel to a plane of said ground plane element with said metal braid in physical engagement with and soldered to said first soldering area; and

a first opening in said ground plane through which said center conductor extends generally vertically upward to terminate in physical engagement with and soldered to said second soldering area.

20. The patch antenna of claim 19 including:

a second opening in said radiating element within said second soldering area, said center conductor extends generally vertically upward and through said second opening and soldered to said top surface of said radiating patch.

21. The patch antenna of claim 19 including:

a first cable mechanical strain relief tab formed in said ground plane, said first strain relief comprising a first generally linear metal mounting tab that is cut from said ground plane and bent down from said bottom surface of said ground plane, said first mounting tab extending in said given direction of current flow.

22. The patch antenna of claim 21, including:

a GPS antenna useful for location determination mounted on said top surface of said ground plane, said GPS antenna having a cable extending therefrom; and

a second cable mechanical strain relief tab formed in said ground plane, said second strain relief comprising a second generally linear metal mounting tab that is cut from said ground plane and bent down from said bottom surface of said ground plane, said second mounting tab extending in said given direction of current flow.

23. The patch antenna of claim 22 including:

a second opening in said radiating element within said second soldering area, said center conductor extends generally vertically upward and through said second opening and soldered to said top surface of said radiating patch.

24. The patch antenna of claim 22 wherein said antenna is a quarter wave antenna.