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reflectorCylindrical

Create cylindrical reflector-backed antenna

Since R2020b

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Description

The default reflectorCylindrical object creates a cylindrical reflector-backed antenna resonating around 1 GHz. The cylindrical shape of the reflector allows you to focus the signal to the antenna surface. Cylindrical reflectors are widely used as high-gain apertures fed with line sources and in airborne navigational antennas where sharp azimuthal beams and wide-angle vertical coverage is required.

Cylindrical reflector antenna geometry, default radiation pattern, and impedance plot.

Creation

Syntax

ant = reflectorCylindrical
ant = reflectorCylindrical(Name=Value)

Description

ant = reflectorCylindrical creates a cylindrical reflector-backed antenna with default property values. The default cylindrical reflector antenna object has a center-fed dipole on the xy-plane as an exciter. The default dimensions are chosen for an operating frequency of around 1 GHz.

example

ant = reflectorCylindrical(Name=Value) sets properties using one or more name–value arguments. Name is the property name and Value is the corresponding value. You can specify several name-value arguments in any order as Name1=Value1,...,NameN=ValueN. Properties that you do not specify, retain their default values.

For example, reflectorCylindrical(GroundPlaneWidth=0.21) creates a cylindrical reflector with a width of 0.21 meters.

example

Properties

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Exciter antenna or array type, specified as either:

  • Antenna object from the catalog (except reflector type, cavity type and platform-installed antennas)

  • Array object from the catalog (except conformal and infinite arrays)

  • Custom antennas: customAntennaGeometry, customAntennaMesh, customAntenna

  • Empty array

To create the reflector backing structure without an exciter, specify this property as an empty array.

Example: dipole

Example: linearArray(Element=patchMicrostrip)

Example: customAntenna

Example: []

Reflector length along X-axis, specified as a positive scalar in meters.

Example: 0.6

Data Types: double

Reflector width along Y-axis, specified as a positive scalar in meters.

Example: 0.4

Data Types: double

Distance between reflector and exciter, specified as a scalar in meters.

Example: 0.059

Data Types: double

Perpendicular distance between the ground plane and the aperture of the cylindrical reflector, specified as a positive scalar in meters.

Example: 0.09

Note

Depth should be less than or equal to half of the GroundPlaneLength.

Data Types: double

Flag to enable the probe feed, specified as 0 or 1. Setting the flag to 0 disables the probe feed, and setting the flag to 1 enables it.

Example: 1

Data Types: double

Type of the metal used as a conductor, specified as a metal material object. You can choose any metal from the MetalCatalog or specify a metal of your choice. For more information, see metal. For more information on metal conductor meshing, see Meshing.

Example: metal("Copper")

Tilt angle of the antenna in degrees, specified as a scalar or vector. For more information, see Rotate Antennas and Arrays.

Example: 90

Example: Tilt=[90 90],TiltAxis=[0 1 0;0 1 1] tilts the antenna at 90 degrees about the two axes defined by the vectors.

Data Types: double

Tilt axis of the antenna, specified as one of these values:

  • Three-element vector of Cartesian coordinates in meters. In this case, each coordinate in the vector starts at the origin and lies along the specified points on the x-, y-, and z-axes.

  • Two points in space, specified as a 2-by-3 matrix corresponding to two three-element vectors of Cartesian coordinates. In this case, the antenna rotates around the line joining the two points.

  • "x", "y", or "z" to describe a rotation about the x-, y-, or z-axis, respectively.

For more information, see Rotate Antennas and Arrays.

Example: [0 1 0]

Example: [0 0 0;0 1 0]

Example: "Z"

Data Types: double | string

Lumped elements added to the antenna feed, specified as a lumpedElement object. You can add a load anywhere on the surface of the antenna. By default, the load is at the feed. For more information, see lumpedElement.

Example: Load=lumpedelements, where lumpedelements is the load added to the antenna feed.

Example: lumpedElement(Impedance=75)

Object Functions

axialRatioCalculate and plot axial ratio of antenna or array
bandwidthCalculate and plot absolute bandwidth of antenna or array
beamwidthBeamwidth of antenna
currentCurrent distribution on antenna or array surface
chargeCharge distribution on antenna or array surface
designDesign prototype antenna or arrays for resonance around specified frequency or create AI-based antenna from antenna catalog objects
efficiencyCalculate and plot radiation efficiency of antenna or array
EHfieldsElectric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays
feedCurrentCalculate current at feed for antenna or array
impedanceCalculate and plot input impedance of antenna or scan impedance of array
infoDisplay information about antenna, array, or platform
memoryEstimateEstimate memory required to solve antenna or array mesh
meshMesh properties of metal, dielectric antenna, or array structure
meshconfigChange meshing mode of antenna, array, custom antenna, custom array, or custom geometry
msiwriteWrite antenna or array analysis data to MSI planet file
optimizeOptimize antenna or array using SADEA optimizer
patternPlot radiation pattern and phase of antenna or array or embedded pattern of antenna element in array
patternAzimuthAzimuth plane radiation pattern of antenna or array
patternElevationElevation plane radiation pattern of antenna or array
peakRadiationCalculate and mark maximum radiation points of antenna or array on radiation pattern
rcsCalculate and plot monostatic and bistatic radar cross section (RCS) of platform, antenna, or array
resonantFrequencyCalculate and plot resonant frequency of antenna
returnLossCalculate and plot return loss of antenna or scan return loss of array
showDisplay antenna, array structures, shapes, or platform
sparametersCalculate S-parameters for antenna or array
stlwriteWrite mesh information to STL file
vswrCalculate and plot voltage standing wave ratio (VSWR) of antenna or array element

Examples

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Open Live Script

Create a cylindrical reflector antenna object with default properties.

ant = reflectorCylindrical;

View the antenna object.

show(ant)

Figure contains an axes object. The axes object with title reflectorCylindrical antenna element, xlabel x (mm), ylabel y (mm) contains 5 objects of type patch, surface. These objects represent PEC, feed.

Open Live Script

Create a reflectorCylindrical antenna object with a rounded bow-tie dipole antenna as an exciter.

b = bowtieRounded(Length=96e-3,Tilt=90,TiltAxis=[0 1 0]);
r = reflectorCylindrical(Exciter=b,Spacing=100e-3);

View the antenna object.

figure
show(r)

Figure contains an axes object. The axes object with title reflectorCylindrical antenna element, xlabel x (mm), ylabel y (mm) contains 5 objects of type patch, surface. These objects represent PEC, feed.

Plot the radiation pattern at 1.5 GHz.

figure
pattern(r,1.5e9)

Figure contains 2 axes objects and other objects of type uicontrol. Axes object 1 contains 5 objects of type patch, surface. Hidden axes object 2 contains 18 objects of type surface, line, text, patch.

Enable the probe feed for the reflectorCylindrical antenna object.

re = reflectorCylindrical(Exciter=b,Spacing=100e-3,EnableProbeFeed=1);

View the antenna object with the probe feed enabled.

figure
show(re)

Figure contains an axes object. The axes object with title reflectorCylindrical antenna element, xlabel x (mm), ylabel y (mm) contains 5 objects of type patch, surface. These objects represent PEC, feed.

Plot the radiation pattern of the antenna object at 1.5 GHz with the probe feed enabled.

figure
pattern(re,1.5e9)

Figure contains 2 axes objects and other objects of type uicontrol. Axes object 1 contains 5 objects of type patch, surface. Hidden axes object 2 contains 17 objects of type surface, line, text, patch.

Open Live Script

Create a linear array of crossed dipole antenna.

d = dipoleCrossed(Tilt=90,TiltAxis=[0 1 0]);
la = linearArray(Element=d,NumElements=4,ElementSpacing=0.05,Tilt=90,TiltAxis=[0 0 1]);

Create a cylindrical reflector backed array.

ant = reflectorCylindrical(Exciter=la,Tilt=90)
ant = 
  reflectorCylindrical with properties:

              Exciter: [1x1 linearArray]
    GroundPlaneLength: 0.2000
     GroundPlaneWidth: 0.2000
              Spacing: 0.0750
                Depth: 0.0750
      EnableProbeFeed: 0
            Conductor: [1x1 metal]
                 Tilt: 90
             TiltAxis: [1 0 0]
                 Load: [1x1 lumpedElement]


show(ant)

Figure contains an axes object. The axes object with title reflectorCylindrical antenna element, xlabel x (mm), ylabel y (mm) contains 19 objects of type patch, surface. These objects represent PEC, feed.

Open Live Script

Create a cylindrical reflector-backed Minkowski's loop fractal antenna.

e = fractalIsland(Substrate=dielectric("Teflon"),Tilt=90,TiltAxis=[0 0 1]);
ant = reflectorCylindrical(Exciter=e)
ant = 
  reflectorCylindrical with properties:

              Exciter: [1x1 fractalIsland]
    GroundPlaneLength: 0.2000
     GroundPlaneWidth: 0.2000
              Spacing: 0.0750
                Depth: 0.0750
      EnableProbeFeed: 0
            Conductor: [1x1 metal]
                 Tilt: 0
             TiltAxis: [1 0 0]
                 Load: [1x1 lumpedElement]


show(ant)

Figure contains an axes object. The axes object with title reflectorCylindrical antenna element, xlabel x (mm), ylabel y (mm) contains 7 objects of type patch, surface. These objects represent PEC, feed, Teflon.

References

[1] Balanis, Constantine A. Antenna Theory: Analysis and Design. 3rd ed. Hoboken, NJ: John Wiley, 2005.

Version History

Introduced in R2020b

See Also

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