Broadband antenna using a semicircular radiator

• US 5,872,546 A
• Filed: 09/17/1996
• Issued: 02/16/1999
• Est. Priority Date: 09/27/1995
• Status: Expired due to Term

• Current Assignee: NTT Mobile Communications Network Inc. (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Mobile Communications Network Inc. (Nippon Telegraph and Telephone Corporation)
• Inventors: Tsunekawa, Koichi, Ihara, Taisuke, Kijima, Makoto
• Primary Examiner(s): Wimer, Michael C.
• Application Number:
  US08/714,262
• Time in Patent Office: 882 Days
• Field of Search: 343/767, 343/770, 343/807, 343/797, 343/895, 343/795, 343/829, 343/830, 343/893, 343/896, 343/897, 343/898, 343/846
• US Class Current: 343/795
• 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
• CPC Class Codes: H01Q 9/40 Element having extended radiating surface
• CPC Class Codes: H01Q 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength
• CPC Class Codes: H01Q 9/46 with rigid elements diverging from single point

Abstract

In a broadband antenna using a semicircular conductor disc, a semicircular cutout is formed in the semicircular radiator concentrically therewith. Alternatively, a semicircular arcwise radiating conductor with a semicircular cutout defined concentrically therewith is bent into a cylindrical shape to form a radiator.

Claims

1. An antenna comprising:

a first radiator formed by a substantially semicircular conductor disc, said disc including a substantially semicircular cutout concentrically therewith forming a semicircular arc;

a plane conductor ground plate disposed opposed to said semicircular arc of said first radiator at right angles thereto; and

a feeder connected to the vertex of the semicircular arc of said first radiator and said plane conductor ground plate, for feeding power across said first radiator and said ground plate.

2. The antenna of claim 1, further comprising a second radiator of about the same shape as that of said first radiator, said second radiator and said first radiator having center axes, respectively, which are coincident with one another.

6. The antenna of claim 1 or 3, further comprising at least one radiating element different in shape from said first radiator placed in said cutout and connected to the vicinity of said feeding point of said first radiator.

7. The antenna of claim 6, wherein said at least one radiating element is any one of a meander monopole, a resistance-loaded monopole and a helical antenna.

3. An antenna comprising:

a first radiator formed by a substantially semicircular arcwise conductor having a semicircular cutout defined concentrically therewith to form a semicircular arc;

a second radiator formed by a substantially semicircular conductor disc and disposed with a vertex of said semicircular conductor disc opposed to a vertex of said semicircular arc of said first radiator; and

a feeder connected to said vertexes of said first and second radiators, for feeding power across said first and second radiators.

4. The antenna of claim 3, further comprising:

a third radiator of about the same shape as that of said first radiator, said third radiator crossing said first radiator with the vertexes of their semicircular arcs held at the same point and having their center axes coincident with one another; and

a fourth radiator of about the same shape as that of said second radiator, said fourth radiator crossing said second radiator with the vertexes of their semicircular conductor discs held at the same point and having their center axes coincident with one another.

5. The antenna of claim 3, wherein said second radiator has a semicircular cutout defined concentrically with its semicircular conductor disc.

8. An antenna comprising:

a radiator formed by a substantially semicircular conductor disc bent into a cylindrical shape;

a plane conductor ground plate disposed opposite and apart from a vertex of a semicircular peripheral arc of said disc at substantially right angles to the generating line of said cylindrical shape; and

a feeder connected to the vertex of said semicircular arc and to said plane conductor ground plate for feeding power across said radiator and said ground plate.

9. An antenna comprising:

a radiator formed by a first substantially semicircular conductor disc bent into a cylindrical shape;

another radiator formed by a second semicircular conductor disc having a center line aligned with a center line of said first semicircular conductor disc, said second semicircular conductor disc having a vertex opposed to a vertex of a peripheral semicircular arc of said first conductor disc apart therefrom; and

a feeder connected to the vertexes of the semicircular arcs of said first and second conductor discs, for feeding power across said radiator and said another radiator.

10. The antenna of claim 9, wherein said another radiator is a cylindrical radiator formed by winding said second semicircular conductor disc into a substantially cylindrical shape.

11. The antenna of claim 9, wherein the first mentioned radiator has a substantially semicircular cutout defined substantially concentrically with the semicircular shape of its said conductor disc.

12. The antenna of claim 11, wherein at least one radiating element different in shape from the semicircular disc of the first mentioned radiator is placed in said cutout and connected to the first mentioned radiator.

13. The antenna of claim 12, wherein said at least one radiating element is any one of a meander monopole, a resistance-loaded monopole and a helical antenna.