Multiple Frequency Antenna

• US 20090284441A1
• Filed: 10/11/2007
• Published: 11/19/2009
• Est. Priority Date: 12/12/2006
• Status: Active Grant

• Current Assignee: Harada Industry Company Limited
• Original Assignee: Nippon Antena Kabushiki Kaisha (Nippon Antenna Company Limited)
• Inventors: Wakui, Masashi
• Granted Patent: US 8,159,404 B2
• Time in Patent Office: Days
• US Class Current: 343/895
• CPC Class Codes: H01Q 1/362 for broadside radiating helical antennas
• CPC Class Codes: H01Q 5/00 Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements combinations of separate active antenna units operating in different wavebands and connected to a common feeder system H01Q21/30
• CPC Class Codes: H01Q 5/371 Branching current paths
• CPC Class Codes: H01Q 5/40 Imbricated or interleaved structures; Combined or electromagnetically coupled arrangements, e.g. comprising two or more non-connected fed radiating elements
• CPC Class Codes: H01Q 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence

Abstract

A helical element, which is operated in the frequency band of FM broadcast, is wound around the outer periphery of a rod-shaped support member 10. A line-shaped element 12, which is operated in the frequency band of terrestrial digital television broadcast, is disposed in a first groove 10a of a predetermined length formed on the outer periphery of the support member 10 from the lower end thereof. With this arrangement, a multi-frequency antenna 1, which is operated in the frequency band of FM broadcast and the frequency band of terrestrial digital television broadcast, can be arranged, and the entire length L of the helical element can be reduced and it can be operated in a plurality of frequency bands with the effect of the line-shaped element 12.

Claims

1. A multi-frequency antenna comprising:

an insulation support member formed in a rod shape and having a groove portion of a predetermined length formed on the outer periphery thereof from the one end thereof substantially parallel along the central axis thereof;

a helical element wound around the outer periphery of the support member, to the helical element, power is supplied from the one end thereof, and the helical element is operated in a first frequency band;

a line-shaped element disposed in the groove portion formed in the support member, to the line-shaped element, power is supplied from the end thereof and the line-shaped element is operated in a second frequency band; and

an element fitting fitted with the one end of the support member, electrically connected to the one end of the helical element and to the end of the line-shaped element, and having an attachment portion formed in the lower portion thereof,

wherein the power is supplied to the helical element and the line-shaped element through the element fitting.

2. The multi-frequency antenna according to claim 1, wherein the support member is formed of flexible resin, and a helical groove, around which the helical element is wound, is formed around the outer periphery of the support member.

3. The multi-frequency antenna according to claim 1, wherein a plurality of groove portions of a predetermined length are formed on the outer periphery of the support member from the one end thereof substantially parallel along the central axis thereof, a plurality of line-shaped elements, which are operated in different frequency bands, are disposed in the respective groove portions, the plurality of line-shaped elements are connected to the element fitting, and power is supplied to the helical element and the plurality of line-shaped elements through the element fitting.

4. The multi-frequency antenna according to claim 1, wherein the line-shaped element disposed in the groove portion is disposed therein by being separated from the helical element at a predetermined interval.

8. The multi-frequency antenna according to claim 2, wherein the line-shaped element disposed in the groove portion is disposed therein by being separated from the helical element at a predetermined interval.

9. The multi-frequency antenna according to claim 3, wherein the line-shaped element disposed in the groove portion is disposed therein by being separated from the helical element at a predetermined interval.

10. The multi-frequency antenna according to claim 1, wherein the line-shaped element disposed in the groove portion is covered with an insulation tube with a predetermined thickness so that the line-shaped element is disposed by being separated from the helical element at a predetermined interval.

11. The multi-frequency antenna according to claim 2, wherein the line-shaped element disposed in the groove portion is covered with an insulation tube with a predetermined thickness so that the line-shaped element is disposed by being separated from the helical element at a predetermined interval.

12. The multi-frequency antenna according to claim 3, wherein the line-shaped element disposed in the groove portion is covered with an insulation tube with a predetermined thickness so that the line-shaped element is disposed by being separated from the helical element at a predetermined interval.

5-7. -7. (canceled)