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 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 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: 'P1-P2'

Data Types: char

FeedLocation — Cartesian coordinates of antenna feed point

[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: [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: 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: metal("Copper")

Load — Lumped elements

[1x1 lumpedElement] (default) | lumpedElement object

Lumped elements added to the antenna feed, specified a lumpedElement object.

Example: lumpedElement(Impedance=75)

Tilt — Tilt angle of antenna

0 (default) | scalar | vector

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

TiltAxis — Tilt axis of antenna

[1 0 0] (default) | three-element vector | 2-by-3 matrix | "X" | "Y" | "Z"

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

Object Functions

show	Display antenna, array structures, shapes, or platform
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 or embedded electric and magnetic fields of antenna element in arrays
impedance	Input impedance of antenna or scan impedance of array
mesh	Mesh properties of metal, dielectric antenna, or array structure
meshconfig	Change meshing mode of antenna, array, custom antenna, custom array, or custom geometry
pattern	Plot radiation pattern and phase of antenna or array or embedded pattern of antenna element in array
patternAzimuth	Azimuth plane radiation pattern of antenna or array
patternElevation	Elevation plane radiation pattern of antenna or array
rcs	Calculate and plot radar cross section (RCS) of platform, antenna, or array
returnLoss	Return loss of antenna or scan return loss of array
sparameters	Calculate S-parameters for antennas and antenna arrays
vswr	Voltage standing wave ratio (VSWR) of antenna or array element

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)

Design 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 and get the coordinates of their vertices.

pr = antenna.Rectangle(Length=0.5,Width=0.5);
boundary_1 = getShapeVertices(pr);

pr1 = antenna.Rectangle(Length=0.02,Width=0.4);
boundary_2 = getShapeVertices(pr1);

pr2 = antenna.Rectangle(Length=0.03,Width=0.008);

Create a circle of radius 0.05 m.

ph = antenna.Circle(Radius=0.05);
boundary_4 = getShapeVertices(ph);

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

pf = translate(pr2,[0 0.1 0]);
boundary_3 = getShapeVertices(pf);

Use customAntennaGeometry object to create a custom slot antenna shape. Specify the shape boundaries and add/subtract operations to get the desired shape. Set the feed location and feed width. View the custom slot antenna.

c = customAntennaGeometry;
c.Boundary = {boundary_1, boundary_2, boundary_3, boundary_4};
c.Operation = 'P1-P2-P4+P3';
c.FeedWidth = 0.01;
c.FeedLocation = [0 0.1 0];
figure
show(c)

Analyze the impedance of the antenna in 300 MHz to 800 MHz frequency range.

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