Patent · US Expired

Low profile tri-filar, single feed, circularly polarized helical antenna

US6816127B2 · kind B2 · utility

9Cited by
3References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 15, 2003
Grant dateNov 9, 2004
Priority date
Expiry dateJul 15, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01Q9/42
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A low-profile, tri-filar, helix antenna having circular polarization (CP) includes a single feed, in the absence of an internal feed network. The antenna includes three metal, bent, quarter-wave monopoles that are physically positioned at 0, 120, and 240 degrees, respectively, on a top flat surface of the antenna. One of the monopoles is directly-fed, and the other two monopoles are parasitically coupled to the directly-fed monopole. Metal perturbations on one or both of the two parasitic monopoles control their coupling-phase to the directly-fed monopole. One of the parasitic monopoles couples at positive 120 degrees to the directly-fed monopole, and the other parasitic monopole couples at negative 120 degrees to the directly-fed monopole. Various perturbation options generate this CP phasing. One of the parasitic monopoles can have a capacitive shunt, and the other parasitic monopole can have a series inductance, or only one parasitic monopole can include a perturbation, either capacitive or inductive, depending on the sense of the CP that is desired. The three monopoles are supported by a dielectric substrate, or they are free-standing. A ground plane is provided directly under …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.