Cobra antenna

Patent metadata

Field	Value
Publication number	US-9837708-B2
Application number	US-201113635933-A
Country	US
Kind code	B2
Filing date	Mar 14, 2011
Priority date	Mar 26, 2010
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

The present invention relates to a small cobra antenna that has a high performance as an antenna gain, and minimizes the effect of the length of the coaxial wire.
An antenna element and a coaxial wire are connected to a junction that is a feeding point. The antenna element has a length corresponding to the frequency of a broadcast wave to be received. Further, a ferrite core is positioned at a location a length identical to the length of the antenna element away from the junction. The coaxial wire is wound around the ferrite core about once to three times. A high frequency interrupting part for interrupting the high-frequency current from the coaxial wire is provided at the front side of a connecter of a receiver to which the other end of the coaxial wire is connected.

First claim

The invention claimed is:

1. An antenna, comprising:
a junction constituting a feeding point, wherein the junction is present on a substrate;
an antenna element electrically coupled to a first terminal of the junction and having a length corresponding to a frequency of a broadcast wave to be received;
a coaxial wire with a first end electrically coupled to a second terminal of the junction;
a first ferrite core provided on the coaxial wire at a position, where a length of the coaxial wire determined from the second terminal of the junction is equal to a length of the antenna element up to the first terminal of the junction, wherein the coaxial wire is wound around the first ferrite core; and
a high frequency interrupting part, provided at a front of a receiver to which a second end of the coaxial wire is coupled to interrupt a high-frequency current from the coaxial wire.

2. The antenna according to claim 1 , wherein the high frequency interrupting part has a high impedance against a high-frequency wave and the high frequency interrupting part is a second ferrite core through which the coaxial wire passes or around which the coaxial wire is wound.

3. The antenna according to claim 1 , wherein the length of the antenna element and a length of the coaxial wire from the second terminal of the junction to the first ferrite core is one fourth of a wavelength of a frequency received of the broadcast wave.

4. The antenna according to claim 1 ,
wherein the antenna element coupled to the first terminal of the junction is constituted of a core part that includes a core wire, and
wherein the core wire of the antenna element is electrically coupled to the core wire of the coaxial wire at the junction.

Assignees

• Yoshino Yoshitaka
• Tsuboi Satoru
• Sony Corp

Inventors

• Yoshino Yoshitaka
• Tsuboi Satoru

Classifications

• H01Q9/16

  with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole (H01Q9/44 takes precedence) · CPC title

• H01Q1/3291 Primary

  mounted in or on other locations inside the vehicle or vehicle body · CPC title

• H01Q9/30

  with feed to end of elongated active element, e.g. unipole (H01Q9/44 takes precedence) · CPC title