fractalKoch

Create Koch curve fractal dipole or loop antenna on X-Y plane

Description

The fractalKoch object creates a Koch curve fractal dipole or loop antenna on an X-Y plane. These fractals are used in multiband and wideband applications like Global System for Mobile Communications (GSM), Universal Mobile Telecommunication Service (UMTS), and Bluetooth.

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, respectively.

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

Creation

Description

example

ant = fractalKoch creates a Koch curve fractal antenna on an X-Y plane. The default is a dipole with Koch curve length chosen for an operating frequency of 0.86 GHz.

example

ant = fractalKoch(Name,Value) sets properties using one or more name-value pairs. For example, ant = fractalKoch('Numiterations',4) creates a Koch curve fractal antenna with four iterations. Enclose each property name in quotes.

Output Arguments

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Koch curve fractal antenna, returned as a fractalKoch object.

Properties

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

Example: 'NumIterations',2

Example: ant.NumIterations = 2

Data Types: double

Length of the Koch curve 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 Koch curve along y-axis, specified as a positive scalar integer in meters.

Example: 'Width',0.0050

Example: ant.Width = 0.0050

Data Types: double

Type of Koch configuration, specified as 'dipole' or 'loop'.

Example: 'Type','loop'

Example: ant.Type = 'loop'

Data Types: char | string

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 default Koch curve fractal antenna.

ant = fractalKoch
ant = 
  fractalKoch with properties:

    NumIterations: 2
           Length: 0.0600
            Width: 1.0000e-03
             Type: 'dipole'
             Tilt: 0
         TiltAxis: [1 0 0]
             Load: [1x1 lumpedElement]

show(ant)

Create and view a Koch loop fractal antenna with three iterations.

ant = fractalKoch('NumIteration',3,'Type','loop');
show(ant)

Introduced in R2018b