Omnidirectional broadband antennas

Patent metadata

Field	Value
Publication number	US-2016226145-A1
Application number	US-201615096477-A
Country	US
Kind code	A1
Filing date	Apr 12, 2016
Priority date	Nov 7, 2013
Publication date	Aug 4, 2016
Grant date	—

Abstract

Disclosed are exemplary embodiments of omnidirectional broadband antennas. In an exemplary embodiment, an antenna generally includes a ground element, an antenna element, and an annular patch element. The antenna element may be electrically isolated from the ground element. The antenna element may include at least one portion that is substantially conical, substantially pyramidal, and/or that tapers in a longitudinal direction. The annular patch element is electrically grounded to the ground element. The annular patch element surrounds at least a portion of the antenna element and is parasitically coupled to the antenna element.

First claim

What is claimed is:

1 . An omnidirectional broadband antenna comprising:
a ground element; an antenna element electrically isolated from the ground element, the antenna element having at least one portion that is substantially conical, that is substantially pyramidal, and/or that tapers in a longitudinal direction; and an annular patch element electrically grounded to the ground element, the annular patch element surrounding at least a portion of the antenna element and parasitically coupled to the antenna element.

2 . The antenna of any one of claim 1 , wherein:
the annular patch element is configured to radiate a vertically polarized wave omnidirectionally in the azimuth plane in a first lower frequency band from 380 to 520 MHz, such that the directional gain of the antenna is substantial in the azimuth plane, while the ripple of the radiation pattern is very low in the azimuth plane and without disturbing an omnidirectional radiation pattern emanating from the antenna element at a second higher frequency band from 700 to 6000 MHz; and/or the presence of the annular patch element makes the antenna electrically small for the first lower frequency band; and/or the annular patch element makes the electrical fields be uniform and of about equal strength for all angles in the azimuth plane for an entire operating band of the antenna.

3 . The antenna of claim 1 , wherein the annular patch element is an electrically-conductive ring having an opening in which is positioned the at least a portion of the antenna element.

4 . The antenna of claim 1 , wherein:
the antenna element has an exponentially tapered form; and/or the antenna element has sides that are outwardly curved or convex sides such that a separation of the sides increases as an exponential function of length.

5 . The antenna of claim 1 , wherein the entire antenna element has a cone shape.

6 . The antenna of claim 1 , wherein the at least one portion of the antenna element conically widens in a longitudinal direction

7 . The antenna of claim 1 , wherein the at least one portion of the antenna element has a cone shape.

8 . The antenna of claim 1 , wherein the at least one portion of the antenna element has a pyramid shape.

9 . The antenna of claim 1 , wherein the at least one portion of the antenna element has sides that taper in the longitudinal direction to a point.

10 . The antenna of claim 1 , wherein the at least one portion of the antenna element is conical, and the antenna element includes another portion that is frustoconical.

11 . The antenna of claim 1 , wherein the at least one portion of the antenna element is conical, and the antenna element includes another portion that is cylindrical.

12 . The antenna of claim 1 , wherein the at least one portion of the antenna element has a hexagonal pyramidal shape, and the antenna element includes another portion that has a hexagonal shape.

13 . The antenna of claim 1 , wherein the entire antenna element has a cone shape having a circular base and sides that conically taper from the circular base to a point.

14 . The antenna of claim 1 , further comprising an antenna element holder connected to the ground element, the antenna element holder operable for holding the antenna element in place such that that antenna element is electrically isolated from the ground element.

15 . The antenna of claim 1 , wherein:
the antenna further comprises a coaxial plug element having an inner conductor and an outer conductor; the ground element has an opening; the outer conductor is electrically coupled to the ground element; and the inner conductor passes through the opening and is electrically coupled to the antenna element.

16 . The antenna of claim 1 , further comprising a radome coupled to the ground element, wherein the antenna element and annular patch element are within an internal space cooperatively defined between the radome and the ground element.

17 . The antenna of claim 1 , further comprising one or more grounding pins connected between the annular patch element and the ground element for electrically grounding the annular patch element to the ground element.

18 . The antenna of claim 1 , further comprising one or more support pins connected between the annular patch element and the ground element for supporting the annular patch element such that the annular patch element is spaced apart from and generally parallel to the ground element.

19 . The antenna of claim 1 , wherein:
the antenna is configured for mounting to a ceiling inside of a building; and the antenna is vertically polarized and operable at a range of operating frequencies between about 380 MHz and about 6000 MHz, including the public safety frequency (TETRA), whereby the annular patch antenna element is configured to be operable as a λ/4 wave trap for an operating frequency band of 400 MHz to thereby broaden bandwidth.

20 . A distributed antenna system including the antenna of claim 1 .

Assignees

• Laird Technologies Inc

Inventors

• Xu Yuan
• Petropoulos Athanasios
• Johnson Shawn Wayne

Classifications

• H01Q21/24

  Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction {(circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001)} · CPC title

• H01Q9/28

  Conical, cylindrical, cage, strip, gauze, or like elements having an extended radiating surface; Elements comprising two conical surfaces having collinear axes and adjacent apices and fed by two-conductor transmission lines (waveguide horns or mouths H01Q13/00; slot antennas H01Q13/00) · CPC title

• H01Q19/005

  Patch antenna using one or more coplanar parasitic elements · CPC title

• H01Q9/40

  Element having extended radiating surface · CPC title

• H01Q9/02

  Non-resonant antennas · CPC title