cloverleaf

Create three-petal cloverleaf antenna

Description

Use the cloverleaf object to create a three-petal cloverleaf antenna. The default cloverleaf has 3 petals and operates at around 5.8 GHz. It has a wideband circular polarization and an omnidirectional antenna.

Creation

Syntax

cl = cloverleaf

cl = cloverleaf(Name,Value)

Description

cl = cloverleaf creates a three-petal cloverleaf antenna.

cl = cloverleaf(Name,Value) sets properties using one or more name-value pairs. For example, cl = cloverleaf('NumPetals',4) creates a five petal cloverleaf antenna. Enclose each property name in quotes.

Properties

NumPetals — Number of petals

3 (default) | scalar

Number of petals, specified as a scalar.

Example: 'NumPetals',4

Example: cl.NumPetals = 4

Data Types: double

PetalLength — Total length of leaf

0.0515 (default) | scalar

Total length of leaf, specified as a scalar in meters.

Example: 'PetalLength',0.0025

Example: cl.PetalLength = 0.0025

Data Types: double

PetalWidth — Leaf strip width

8.0000e-04 (default) | scalar

Leaf strip width, specified as a scalar in meters.

Example: 'PetalWidth',0.001

Example: cl.PetalWidth = 0.001

Data Types: double

FlareAngle — Leaf flare angle

105 (default) | scalar

Leaf flare angle, specified as a scalar in degrees.

Example: 'FlareAngle',100

Example: cl.FlareAngle = 100

Data Types: double

Load — Lumped elements

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

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, it is at the origin. For more information, see lumpedElement.

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

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

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 degree about two axes, defined by vectors.

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 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

show	Display antenna or array structure; Display shape as filled patch
info	Display information about antenna or array
axialRatio	Axial ratio of antenna
beamwidth	Beamwidth of antenna
charge	Charge distribution on metal or dielectric antenna or array surface
current	Current distribution on metal or dielectric antenna or array surface
design	Design prototype antenna or arrays for resonance at specified frequency
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 or 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	S-parameter object
vswr	Voltage standing wave ratio of antenna

Examples

Clover Leaf Antenna

Create and view a default cloverleaf antenna.

cl = cloverleaf

cl = 
  cloverleaf with properties:

      NumPetals: 3
    PetalLength: 0.0515
     PetalWidth: 8.0000e-04
     FlareAngle: 105
           Tilt: 0
       TiltAxis: [1 0 0]
           Load: [1x1 lumpedElement]

show(cl)

Axial Ratio of Cloverleaf Antenna

Create a cloverleaf antenna.

cl = cloverleaf;
show(cl);

Plot the axial ratio of the antenna from 5 GHz to 6 GHz.

freq = linspace(5e9,6e9,101);
axialRatio(cl,freq,0,0);

You can see from the axial ratio plot that the antenna supports circular polarization over the entire frequency range.