fractalCarpet

Create Sierpinski's carpet fractal antenna

Description

The fractalCarpet object creates a Sierpinski's carpet fractal antenna. These fractal antennas are used in mobile phone and Wi-Fi® communications.

A fractal antenna uses a self-similar design to maximize the length or increase the perimeter of a material that transmits or receives electromagnetic radiation within a given volume or area. The main advantage of fractal antennas is that they are compact, which is an important requirement for small and complex circuits. Fractal antennas also have more input impedance or resistance due to increased length or perimeter.

All fractal antennas are printed structures that are etched on a dielectric substrate.

Creation

Description

example

ant = fractalCarpet creates a Sierpinski’s carpet fractal antenna. The default fractal is centered at the origin, and the number of iterations is set to 2. The length of the fractal is for an operating frequency of 5.45 GHz.

example

ant = fractalCarpet(Name,Value) sets properties using one or more name-value pairs. For example, ant = fractalCarpet('Numiterations',4) creates a Sierpinski's carpet with four iterations.

Output Arguments

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Sierpinski's carpet fractal antenna, returned as a fractalCarpet object.

Properties

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Number of iterations performed on the fractal antenna, specified as a scalar integer.

Example: 'NumIterations',4

Example: ant.NumIterations = 4

Data Types: double

Length of the fractal carpet along the X-axis, specified as a positive scalar integer in meters.

Example: 'Length',0.5000

Example: ant.Length = 0.5000

Data Types: double

Width of the fractal carpet along the Y-axis, specified as a positive scalar integer in meters.

Example: 'Width',0.0050

Example: ant.Width = 0.0050

Data Types: double

Height of the fractal carpet above the ground plane along the Z-axis, specified as a positive scalar integer in meters.

Example: 'Height',0.0034

Example: ant.Height = 0.0034

Data Types: double

Width of the feeding strip line, specified as a positive scalar integer in meters.

Example: 'StripLineWidth',0.0050

Example: ant.StripLineWidth = 0.0050

Data Types: double

Type of dielectric material used as a substrate, specified as a dielectric object. For more information, see dielectric.

Example: d = dielectric('FR4'); ant = fractalCarpet('Substrate',d)

Example: d = dielectric('FR4'); ant = fractalCarpet; ant.Substrate = d;

Data Types: string | char

Length of the ground plane, specified as a positive scalar integer in meters.

Example: 'GroundPlaneLength',0.0550

Example: ant.GroundPlaneLength = 0.0550

Data Types: double

Width of the ground plane, specified as a positive scalar integer in meters.

Example: 'GroundPlaneWidth',0.0550

Example: ant.GroundPlaneWidth = 0.0550

Data Types: double

Signed distance of the fractal carpet center from the origin, specified as a two-element real-valued vector with each element unit in meters.

Example: 'FractalCenterOffset',[0 0.080]

Example: ant.FractalCenterOffset = [0 0.080]

Data Types: double

Signed distance of the feed from the origin, specified as a two-element real-valued vector with each element unit in meters.

Example: 'FeedOffset',[0 0.080]

Example: ant.FeedOffset = [0 0.080]

Data Types: double

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

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

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

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 degree about two axes, defined by vectors.

Data Types: double

Tilt axis of the antenna, specified as:

  • Three-element vectors of Cartesian coordinates in meters. In this case, each 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'

Object Functions

showDisplay antenna or array structure; Display shape as filled patch
axialRatioAxial ratio of antenna
beamwidthBeamwidth of antenna
chargeCharge distribution on metal or dielectric antenna or array surface
currentCurrent distribution on metal or dielectric antenna or array surface
designDesign prototype antenna or arrays for resonance at specified frequency
EHfieldsElectric and magnetic fields of antennas; Embedded electric and magnetic fields of antenna element in arrays
impedanceInput impedance of antenna; scan impedance of array
meshMesh properties of metal or dielectric antenna or array structure
meshconfigChange mesh mode of antenna structure
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
returnLossReturn loss of antenna; scan return loss of array
sparametersS-parameter object
vswrVoltage standing wave ratio of antenna

Examples

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Create and view a Sierpinski's carpet fractal antenna with default property values.

ant = fractalCarpet
ant = 
  fractalCarpet with properties:

          NumIterations: 2
                 Length: 0.0280
                  Width: 0.0370
         StripLineWidth: 0.0030
             FeedOffset: [-0.0240 -0.0020]
                 Height: 0.0016
              Substrate: [1x1 dielectric]
      GroundPlaneLength: 0.0480
       GroundPlaneWidth: 0.0480
    FractalCenterOffset: [0 0]
                   Tilt: 0
               TiltAxis: [1 0 0]
                   Load: [1x1 lumpedElement]

show(ant)

Create and view a Sierpinski's carpet fractal antenna on FR4 substrate.

ant = fractalCarpet('Substrate',dielectric('FR4'));
show(ant);

Plot the radiation pattern of the antenna at 5.45 GHz.

pattern(ant,5.45e9)

Introduced in R2019a