WAVEGUIDE OR SLOT RADIATOR FOR WIDE E-PLANE RADIATION PATTERN BEAMWIDTH WITH ADDITIONAL STRUCTURES FOR DUAL POLARIZED OPERATION AND BEAMWIDTH CONTROL
An apparatus and method are provided for producing a wide E-plane half power beamwidth. The apparatus can include a dipole antenna and a complimentary slot antenna in an infinite ground plane. The apparatus can also include a waveguide with surrounding structure that can be adjusted to produce the desired half power beamwidth.
1 . An apparatus comprising:
a dipole antenna; and
a slot antenna complimentary to the dipole antenna, wherein the slot antenna is disposed in a ground plane, wherein dimensions of the dipole antenna are substantially equal to dimensions of the slot antenna, and wherein radiation emitted from slot antenna includes a wide E-plane half power beamwidth.
2 . The apparatus of claim 1 wherein a dominant axis of the dipole antenna is parallel to the E-plane of the radiation.
3 . The apparatus of claim 1 wherein a dominant axis of the slot antenna is orthogonal to the E-plane of the radiation.
4 . The apparatus of claim 1 wherein the dipole antenna emits a first radiation pattern, wherein the slot antenna emits a second radiation pattern, and wherein the first and second radiation patterns are substantially equal.
5 . The apparatus of claim 1 wherein a polarization of the dipole antenna is orthogonal to a polarization of the slot antenna.
6 . An apparatus comprising:
a waveguide defined by a plurality of waveguide walls;
a back plane connected to one end of each of the plurality of waveguide walls to short the waveguide; and
a plurality of adjustable plates connected to open ends of at least some of the plurality of waveguide walls at an angle θ, wherein radiation emitted from the waveguide includes a wide E-plane half power beamwidth.
7 . The apparatus of claim 6 wherein the waveguide is rectangular.
8 . The apparatus of claim 6 wherein at least some of the back plane and the plurality of waveguide walls are metal.
9 . The apparatus of claim 6 wherein the plurality of waveguide walls define an internal dimension α.
10 . The apparatus of claim 9 further comprising an E-plane probe mechanically supported within the waveguide to excite a fundamental mode of the waveguide, wherein the internal dimension α allows the radiation to propagate.
11 . The apparatus of claim 6 wherein a first of the plurality of waveguide walls defines a first side of the waveguide, wherein a second of the plurality of waveguide walls defines a second side of the waveguide, wherein a third of the plurality of waveguide walls defines a third side of the waveguide, and wherein a fourth of the plurality of waveguide walls defines a fourth side of the waveguide.
12 . The apparatus of claim 11 wherein a first of the plurality of adjustable plates is adjustably connected to an open end of the fourth of the plurality of waveguide walls, and wherein a second of the plurality of plates is adjustably connected to an open end of the second of the plurality of waveguide walls.
13 . The apparatus of claim 12 wherein the angle θ is an angle between the second of the plurality of adjustable plates and the first of the plurality of waveguide walls.
14 . The apparatus of claim 13 wherein each of the plurality of adjustable plates includes a length L.
15 . The apparatus of claim 14 wherein the length L and the angle θ are capable of being adjusted to produce a desired impedance and the wide E-plane wide half power beamwidth.
16 . The apparatus of claim 15 wherein, when the angle θ is approximately 35 degrees, the length L is capable of being adjusted from 0 to approximately 1.3 inches to achieve the wide E-plane half power beamwidth of approximately 60 degrees to approximately 165 degrees.
17 . The apparatus of claim 6 further comprising a dipole disposed over an approximate center of the waveguide.
18 . The apparatus of claim 17 wherein a polarization of radiation emitted from the dipole is orthogonal to a polarization of the radiation emitted from the waveguide.
19 . The apparatus of claim 18 further comprising a balun and an impedance transformer deposited on a printed circuit board, wherein the waveguide is disposed on a first side of the back plane, and wherein the printed circuit board is disposed on a second the back plane.
20 . A method comprising:
defining a waveguide with a plurality of waveguide walls;
shorting the waveguide with a back plane connected to one end of each of the plurality of waveguide walls;
providing a plurality of adjustable plates connected to open ends of at least some of the plurality of waveguide walls at an angle θ, each of the plurality of adjustable plates including a length L; and
adjusting the length L and the angle θ to produce a desired impedance and an E-plane half power beamwidth of radiation emitted from the waveguide.