Small-size unidirectional antenna

• US 6,466,178 B1
• Filed: 08/31/2000
• Issued: 10/15/2002
• Est. Priority Date: 08/31/2000
• Status: Expired due to Term

• Current Assignee: InterDigital Madison Patent Holdings (InterDigital, Inc.)
• Original Assignee: Thomson Licensing SA (Vantiva SA)
• Inventors: Muterspaugh, Max Ward
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): CHEN, SHIH CHAO
• Application Number:
  US09/653,603
• Time in Patent Office: 775 Days
• Field of Search: 343/793, 343/803, 343/739, 343/740, 343/795, 343/749
• US Class Current: 343/795
• CPC Class Codes: H01Q 21/205 providing an omnidirectional coverage turnstile aerials H01Q21/26
• CPC Class Codes: H01Q 25/005 providing two patterns of opposite direction; back to back antennas H01Q25/004 takes precedence
• CPC Class Codes: H01Q 3/24 varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
• CPC Class Codes: H01Q 9/26 with folded element or elements, the folded parts being spaced apart a small fraction of operating wavelength resonant loop antennas H01Q7/00

Abstract

A broadband folded dipole antenna has a pair of load resistors in the vicinity of the edges of the antenna element for obtaining a unidirectional beam pattern.

Claims

1. A broadband antenna comprising:

a closely-spaced pair of elongated conductors, each one of said conductors having a length substantially less than half the wave length of a receiving frequency;

a pair of load means each having a respective resistance value for coupling the ends of one of said conductors to the respective ends of the other conductor for providing a unidirectional beam pattern; and

a feed point being located substantially at the center of one of said conductors.

2. The broadband antenna of claim 1 wherein:

the total resistance value of said pair of load means is substantially greater than the total radiation resistance of said pair of conductors at said receiving frequency.

3. The broadband antenna of claim 1 wherein:

said elongated conductors are spaced apart a distance substantially equal to or less than a quarter of the wave length of said receiving frequency.