Planar antenna apparatus

• US 20060061510A1
• Filed: 09/21/2005
• Published: 03/23/2006
• Est. Priority Date: 09/21/2004
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Itsuji, Takeaki
• Granted Patent: US 7,358,918 B2
• Time in Patent Office: Days
• US Class Current: 343/700.MS
• 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

Abstract

An antenna apparatus including a dielectric substrate, a planar antenna element disposed on the substrate, and a waveguide for propagating electromagnetic waves to or from the planar antenna element. The waveguide includes at least a first conductor and a second conductor extending along each other. Near a connection portion formed between the first and second conductors and the planar antenna element, there is provided a taper region in which a distance between mutually-facing edge portions of the first conductor and the second conductor increases approximately monotonically toward the planar antenna element.

Claims

1. An antenna apparatus comprising:

a dielectric substrate;

a planar antenna element disposed on the substrate; and

a waveguide for propagating electromagnetic waves to or from the planar antenna element,

wherein the waveguide comprises at least a first conductor and a second conductor extending along each other, and near a connection portion formed between the first and second conductors and the planar antenna element, there is provided a taper region in which a distance between mutually-facing edge portions of the first conductor and the second conductor increases approximately monotonically toward the planar antenna element.

2. An antenna apparatus according to claim 1, wherein the first conductor comprises a center conductor, and the second conductor comprises at least a grounded conductor.

3. An antenna apparatus according to claim 2, wherein the waveguide is disposed in the same plane as the planar antenna element, and comprises a co-planar waveguide having a center conductor of the first conductor connected to the planar antenna element, and grounded conductors of the second conductor, each of which is formed at a distance from the center conductor on each side of the center conductor.

4. An antenna apparatus according to claim 1, wherein the planar antenna element is a bow-tie antenna element having an isosceles triangular shape with a vertical angle of a desired value.

5. An antenna apparatus according to claim 1, wherein the planar antenna element is a teardrop-shaped antenna element whose shape is composed of a portion of an isosceles triangular shape with a vertical angle of a desired value and an arc of a circle inscribed in the isosceles triangle.

6. An antenna apparatus according to claim 1, wherein the planar antenna element is comprised of teardrop-shaped structures, each composed of a portion of an isosceles triangular shape with a vertical angle of a desired value and an arc of a circle inscribed in the isosceles triangle, arranged with their apexes facing each other.

7. An antenna apparatus according to claim 6, wherein the waveguide is an unbalanced line which is converted into a balanced line via the taper region, and connected to the planar antenna element.

8. An antenna apparatus comprising:

a dielectric substrate; and

a planar antenna element disposed on the substrate,

wherein the planar antenna element comprises teardrop-shaped structures, each composed of a portion of an isosceles triangular shape with a vertical angle of a desired value and an arc of a circle inscribed in the isosceles triangle, arranged with their apexes facing each other.