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reflectorGrid

Create grid reflector-backed antenna

Description

The reflectorGrid object creates a grid reflector-backed antenna. The grid reflector uses a grid of parallel wires or bars oriented in one direction. Grid reflectors can be used as high-gain antennas in point-to-point communications.

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

Creation

Description

example

ant = reflectorGrid creates a grid reflector-backed antenna. The default antenna object has an exciter as a dipole with the feed point located at the origin on the X-Y plane, and the antenna dimensions are chosen for an operating frequency of 1 GHz.

example

ant = reflectorGrid(Name,Value) sets Properties using name-value pairs. For example, reflectorGrid('GroundPlaneWidth',0.6) creates a grid reflector with a width of 0.6 meters. You can specify multiple name-value pairs. Enclose each property name in quotes. Properties not specified retain their default values.

Properties

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Antenna type used as an exciter, specified as any single-element antenna object. Except reflector and cavity antenna elements, you can use any of the antenna elements or array elements in the Antenna Toolbox™ as an exciter.

Example: 'Exciter',horn

Example: ant.Exciter = horn

Example: ant.Exciter = linearArray('patchMicrostrip')

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

Example: 'Spacing',0.259

Example: ant.Spacing = 0.195

Data Types: double

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

Example: 'GroundPlaneLength',0.6

Example: ant.GroundPlaneLength = 0.18

Data Types: double

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

Example: 'GroundPlaneWidth',0.6

Example: ant.GroundPlaneWidth = 0.18

Data Types: double

Type of the grid used in the reflector, specified as either one of the following:

  • 'H' — grids are arranged horizontally in the reflector.

  • 'V' — grids are arranged vertically in the reflector.

  • 'HV' or 'VH' — grids are arranged both horizontally and vertically in the reflector.

Example: 'GridType','H'

Example: ant.GridType = 'V'

Data Types: char

Distance between the two grid cells, specified as a positive scalar in meters.

Example: 'GridSpacing',0.018

Example: ant.GridSpacing = 0.014

Data Types: double

Width of each grid cell, specified as a positive scalar in meters.

Example: 'GridWidth',0.3

Example: ant.GridWidth = 0.28

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: m = metal('Copper'); 'Conductor',m

Example: m = metal('Copper'); ant.Conductor = m

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

Example: 'Tilt',90

Example: ant.Tilt = 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.

Note

The wireStack antenna object only accepts the dot method to change its properties.

Data Types: double

Tilt axis of the antenna, specified as:

  • 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, each specified as three-element vectors of Cartesian coordinates. In this case, the antenna rotates around the line joining the two points in space.

  • A string input describing simple rotations around one of the principal axes, 'X', 'Y', or 'Z'.

For more information, see Rotate Antennas and Arrays.

Example: 'TiltAxis',[0 1 0]

Example: 'TiltAxis',[0 0 0;0 1 0]

Example: ant.TiltAxis = 'Z'

Note

The wireStack antenna object only accepts the dot method to change its properties.

Data Types: double

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: ant.Load = lumpedElement('Impedance',75)

Object Functions

showDisplay antenna or array structure; display shape as filled patch
impedanceInput impedance of antenna; scan impedance of array
sparametersS-parameter object
returnLossReturn loss of antenna; scan return loss of array
vswrVoltage standing wave ratio of antenna
patternRadiation pattern and phase of antenna or array; Embedded pattern of antenna element in array
patternAzimuthAzimuth pattern of antenna or array
patternElevationElevation pattern of antenna or array
axialRatioAxial ratio of antenna
beamwidthBeamwidth of antenna
currentCurrent distribution on metal or dielectric antenna or array surface
chargeCharge distribution on metal or dielectric antenna or array surface
efficiencyRadiation efficiency of antenna
EHfieldsElectric and magnetic fields of antennas; Embedded electric and magnetic fields of antenna element in arrays
meshMesh properties of metal or dielectric antenna or array structure
optimizeOptimize antenna or array using SADEA optimizer
designDesign prototype antenna or arrays for resonance at specified frequency
rcsCalculate and plot radar cross section (RCS) of platform, antenna, or array
numGridsToSpacingCalculate grid spacing in grid for reflectorGrid object

Examples

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Create and view a grid reflector-backed antenna object with default properties.

ant = reflectorGrid;
show(ant)

Figure contains an axes. The axes with title reflectorGrid antenna element contains 5 objects of type patch, surface. These objects represent PEC, feed.

Plot the radiation pattern of the antenna at 1 GHz.

pattern(ant,1e9)

Figure contains an axes and other objects of type uicontrol. The axes contains 5 objects of type patch, surface.

Create and view a grid reflector-backed biquad antenna with an arm length of 0.01 meters.

d = biquad('ArmLength',0.01);
h = reflectorGrid('Exciter',d);
show(h)

Figure contains an axes. The axes with title reflectorGrid antenna element contains 5 objects of type patch, surface. These objects represent PEC, feed.

Plot the radiation pattern of the antenna at 0.6 GHz.

pattern(h,0.6e9)

Figure contains an axes and other objects of type uicontrol. The axes contains 5 objects of type patch, surface.

Create and view grid reflector-baked dipole blade antenna.

d = dipoleBlade('Length',0.1,'TaperLength',0.05,'FeedGap',0.002);
h = reflectorGrid('Exciter',d);
show(h)

Figure contains an axes. The axes with title reflectorGrid antenna element contains 5 objects of type patch, surface. These objects represent PEC, feed.

Change the grid type from 'HV' to 'H'.

h.GridType = 'H';

View the antenna with grid type 'H'.

show(h)

Figure contains an axes. The axes with title reflectorGrid antenna element contains 5 objects of type patch, surface. These objects represent PEC, feed.

Plot the radiation pattern at 1 GHz.

pattern(h,1e9)

Figure contains an axes and other objects of type uicontrol. The axes contains 5 objects of type patch, surface.

Create a rectangular array of cylindrical dipole antennas.

d = dipoleCylindrical('Length',0.2,'Radius',0.005);
arr = rectangularArray('Element',d,'Size',[4 4],'RowSpacing',0.029,'ColumnSpacing',0.029);

Create a grid reflector-backed rectangular array.

ant = reflectorGrid('Exciter',arr,'Spacing',0.2)
ant = 
  reflectorGrid with properties:

              Exciter: [1x1 rectangularArray]
              Spacing: 0.2000
    GroundPlaneLength: 0.2000
     GroundPlaneWidth: 0.2000
             GridType: 'HV'
          GridSpacing: 0.0180
            GridWidth: 0.0220
            Conductor: [1x1 metal]
                 Tilt: 0
             TiltAxis: [1 0 0]
                 Load: [1x1 lumpedElement]

show(ant)

Figure contains an axes. The axes with title reflectorGrid antenna element contains 35 objects of type patch, surface. These objects represent PEC, feed.

References

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

Introduced in R2020b