Planar antenna apparatus

• US 7,542,000 B2
• Filed: 02/26/2008
• Issued: 06/02/2009
• Est. Priority Date: 09/21/2004
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Itsuji, Takeaki
• Primary Examiner(s): CHEN, SHIH CHAO
• Application Number:
  US12/037,780
• Publication Number:
  US 20080165062A1
• Time in Patent Office: 462 Days
• Field of Search: 343/700.MS, 343/772, 343/795, 343/845, 343/846
• US Class Current: 343/772
• 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 apparatus comprising:

a signal source, and

an antenna for emitting an electromagnetic wave according to a signal from the signal source,

wherein said antenna comprises a dielectric substrate, a planar antenna element disposed on the dielectric substrate, and a waveguide for propagating electromagnetic waves to or from the planar antenna element,

wherein said antenna has a wavelength selected between λ

/2 mm and λ

mm, where λ

is a wavelength of the electromagnetic wave passing through the dielectric substrate,

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

wherein a width W mm of the center conductor is constant, and

wherein a distance d between the planar antenna element and the waveguide is 0 mm or more and

$\frac{2<br><br>\sqrt{10.2}}{c}<br><br><br><br>\mathrm{\lambda <br><br>}$

mm or less.

2. An apparatus according to claim 1, wherein the wavelength λ

is

$\frac{c}{4<br><br>\sqrt{10.2}}$

mm at a frequency of 4 GHz and the distance d is 0 mm or more and 0.5 mm or less.