Quadri-filar helix antenna structure
The present invention discloses a quadri-filar helix antenna structure, which comprises a cylindrical body made of a dielectric material with a relative dielectric constant ∈ r greater than 4, and four radiating metal plates disposed on a distal end surface of the cylindrical body and extended along the radial direction of the center of the cylindrical body to its periphery and then along the radial direction in a spiral course on the circumferential surface thereof to its periphery on the other end respectively, wherein the ends of every two adjacent radiating metal plates are coupled with each other to constitute two sets of antenna structures, a penetrating hole is disposed at the central position of the cylindrical body and is precisely embedded into a coaxial cable, and a shield cable disposed at the periphery on one end of the coaxial cable is coupled to an end of another set of antenna structure. Therefore, the antenna not only reduces the overall volume, but also greatly lowers its production costs.
1. A quadri-filar helix antenna, comprising:
a cylindrical body, being made of a dielectric material with a relative dielectric constant ∈ r greater than 4 , and a penetrating hole disposed at its central position;
four radiating metal plates, and an end of said each radiating metal plate being disposed at an end surface of said cylindrical body and extended along the radial direction from the center of said cylindrical body to the periphery of said cylindrical body and then extended in a spiral course along the axial direction from the circumferential surface of said cylindrical body to the periphery at another end of said cylindrical body, and the facing ends of every two adjacent radiating metal plates disposed on one end surface of said cylindrical body being coupled with each other to constitute two sets of antenna structures;
a coaxial cable including an insulator, an electrically conductive shield layer covering said outer surface of the insulator, and a feeder conductor disposed at a central position within said insulator, said coaxial cable including said insulator, electrically conductive shield layer and said feeder conductor being embedded in said penetrating hole of the cylindrical body and both facing ends of said sets of antenna structures being protruded from both ends of said penetrating hole and one end of said electrically conductive shield layer being coupled to one end of one said set of antenna structures and one end of said feeder conductor being coupled to one end of another said set of antenna structures.
2. The quadri-filar helix antenna of claim 1 , wherein said feeder conductor having one end coupled with said another said set of antenna structures passes through said penetrating hole and keeps an insulating gap from said electrically conductive shield layer and is coupled to another end of said electrically conductive shield layer when protruding from another end surface of said cylindrical body.
3. The quadri-filar helix antenna of claim 1 further comprising a through hole disposed on said cylindrical body at a position parallel to said penetrating hole for allowing an end of said feeder conductor to pass through after being coupled to one end of said another said set of antenna structure, and then is protruded from another end surface of said cylindrical body, and said electrically conductive shield layer being coupled to another end of said feeder conductor acting as a feed end of said antenna structure.
4. The quadri-filar helix antenna of claim 2 , wherein said antenna structure has at least one of said radiating metal plates being extended spirally in a meandering course on a circumferential surface of said cylindrical body from a distal end surface of said cylindrical body to another distal end surface of said cylindrical body and surrounding said cylindrical body with a length substantially equal to a quarter of its wavelength.
5. The quadri-filar helix antenna of claim 3 , wherein said antenna structure has at least one of said radiating metal plates being extended spirally in a meandering course on a circumferential surface of said cylindrical body from a distal end surface of said cylindrical body to another distal end surface of said cylindrical body and surrounding said cylindrical body with a length substantially equal to a quarter of its wavelength.
6. The quadri-filar helix antenna of claim 2 , wherein said antenna structure has at least one of said radiating metal plates being extended spirally in a linear course on a circumferential surface of said cylindrical body from a distal end surface of said cylindrical body to another distal end surface of said cylindrical body and surrounding said cylindrical body with a length substantially equal to a quarter of its wavelength.
7. The quadri-filar helix antenna of claim 3 , wherein said antenna structure has at least one of said radiating metal plates being extended spirally in a linear course on a circumferential surface of said cylindrical body from a distal end surface of said cylindrical body to another distal end surface of said cylindrical body and surrounding said cylindrical body with a length substantially equal to a quarter of its wavelength.