customAntennaGeometry

Create antenna represented by 2-D custom geometry

Description

The customAntennaGeometry object is an antenna represented by a 2-D custom geometry on the xy- plane. Using customAntennaGeometry, you can import a planar mesh, define the feed for this mesh to create an antenna, analyze the antenna, and use it in finite or infinite arrays. The image shown is a custom slot antenna.

Creation

Syntax

ca = customAntennaGeometry

ca = customAntennaGeometry(Name,Value)

Description

ca = customAntennaGeometry creates a 2-D antenna represented by a custom geometry, based on the specified boundary.

ca = customAntennaGeometry(Name,Value) creates a 2-D planar antenna geometry, with additional properties specified by one or more name-value pair arguments. Name is the property name and Value is the corresponding value. You can specify several name-value pair arguments in any order as Name1, Value1, ..., NameN, ValueN. Properties not specified retain their default values.

Properties

Boundary — Boundary information in Cartesian coordinates

cell array

Boundary information in Cartesian coordinates, specified as a cell array in meters.

Data Types: double

Operation — Boolean operation performed on boundary list

'P1' (default) | character vector

Boolean operation performed on the boundary list, specified as a character vector.

Example: 'Operation','P1-P2'

Data Types: double

FeedLocation — Antenna feed location in Cartesian coordinates

[0 0 0] (default) | three-element vector

Antenna feed location in Cartesian coordinates, specified as a three-element vector. The three-element vector is the x, y, and z coordinates respectively.

Example: 'FeedLocation', [0 0.2 0]

Data Types: double

FeedWidth — Width of feed section

0.0100 (default) | scalar

Width of feed section, specified as a scalar in meters.

Example: 'FeedWidth',0.05

Data Types: double

Conductor — Type of metal material

'PEC' (default) | metal object

Type of the metal used as a conductor, specified in the 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

Load — Lumped elements

[1x1 lumpedElement] (default) | lumped element object

Lumped elements added to the antenna feed, specified a lumped element object. For more information, see lumpedElement.

Example: 'Load', lumpedelement. lumpedelement is the object for the load created using lumpedElement.

Tilt — Tilt angle of antenna

0 (default) | scalar | vector

Tilt angle of antenna, specified as a scalar or vector with each element unit in degrees.

Example: 'Tilt',90

Example: 'Tilt',[90 90 0]

Data Types: double

Tilt — Tilt angle of antenna

0 (default) | scalar | vector

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: 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

TiltAxis — Tilt axis of antenna

[1 0 0] (default) | three-element vector of Cartesian coordinates | two three-element vectors of Cartesian coordinates | 'X' | 'Y' | 'Z'

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: TiltAxis = 'Z'

Data Types: double

Object Functions

show	Display antenna, array structures or shapes
info	Display information about antenna or array
axialRatio	Axial ratio of antenna
beamwidth	Beamwidth of antenna
charge	Charge distribution on antenna or array surface
current	Current distribution on antenna or array surface
efficiency	Radiation efficiency of antenna
EHfields	Electric and magnetic fields of antennas; Embedded electric and magnetic fields of antenna element in arrays
impedance	Input impedance of antenna; scan impedance of array
mesh	Mesh properties of metal, dielectric antenna, or array structure
meshconfig	Change mesh mode of antenna structure
pattern	Radiation pattern and phase of antenna or array; Embedded pattern of antenna element in array
patternAzimuth	Azimuth pattern of antenna or array
patternElevation	Elevation pattern of antenna or array
returnLoss	Return loss of antenna; scan return loss of array
sparameters	Calculate S-parameter for antenna and antenna array objects
vswr	Voltage standing wave ratio of antenna
rcs	Calculate and plot radar cross section (RCS) of platform, antenna, or array

Examples

Custom Dipole Antenna

Create a custom dipole antenna and view it.

ca = customAntennaGeometry

ca = 
  customAntennaGeometry with properties:

        Boundary: {[4x3 double]}
       Operation: 'P1'
    FeedLocation: [0 0 0]
       FeedWidth: 0.0200
       Conductor: [1x1 metal]
            Tilt: 0
        TiltAxis: [1 0 0]
            Load: [1x1 lumpedElement]

show(ca)

Custom Slot Antenna

Create a custom slot antenna using three rectangles and a circle.

Create three rectangles of dimensions 0.5 m x 0.5 m, 0.02 m x 0.4 m and 0.03 m x 0.008 m.

pr = antenna.Rectangle('Length',0.5,'Width',0.5);
pr1 = antenna.Rectangle('Length',0.02,'Width',0.4);
pr2 = antenna.Rectangle('Length',0.03,'Width',0.008);

Create a circle of radius 0.05 m.

ph = antenna.Circle('Radius',0.05);

Translate the third rectangle to the X-Y plane using the coordinates [0 0.1 0].

pf = translate(pr2,[0 0.1 0]);

Create a custom slot antenna shape by performing add and subtract operations on the above shapes. Then assign this shape as a layer to the pcbStack object. Set the feed location and feed diameter.

s = pr-ph-pr1+pf;
c = pcbStack;
boardShape = antenna.Rectangle('Length',0.6,'Width',0.6);
c.BoardShape = boardShape;
c.Layers = {s}

c = 
  pcbStack with properties:

              Name: 'MyPCB'
          Revision: 'v1.0'
        BoardShape: [1x1 antenna.Rectangle]
    BoardThickness: 0.0100
            Layers: {[1x1 antenna.Polygon]}
     FeedLocations: [-0.0187 0 1 2]
      FeedDiameter: 1.0000e-03
      ViaLocations: []
       ViaDiameter: []
      FeedViaModel: 'strip'
       FeedVoltage: 1
         FeedPhase: 0
         Conductor: [1x1 metal]
              Tilt: 0
          TiltAxis: [1 0 0]
              Load: [1x1 lumpedElement]

c.FeedDiameter = 0.005;
c.FeedLocations = [0 0.1 1];
% View the antenna
figure;
show(c);

Analyze the impedance of the antenna from 300 MHz to 800 MHz.

figure;
impedance(c, linspace(300e6,800e6,51));

Analyze the current distribution of the antenna at 575 MHz.

figure;
current(c,575e6)

Plot the radiation pattern of the antenna at 575 MHz.

figure;
pattern(c,575e6)

References

[1] Balanis, C. A. Antenna Theory. Analysis and Design. 3rd Ed. Hoboken, NJ: John Wiley & Sons, 2005.

Version History

Introduced in R2016b