wireStack

Create single or multifeed wire antenna

Since R2020a

Description

The wireStack object converts all applicable elements in the antenna library to wire antennas with single or multiple feeds. You can now create cylindrical thin-wire antennas and analyze them using with the existing antenna analysis functions.

Note

For some antennas, the wire geometry may be altered to allow the placement of the feed. Please use the show function to view the resulting antenna and verify its shape.

Creation

Syntax

ant = wireStack

ant = wireStack(libant)

Description

ant = wireStack creates a half-wavelength wire dipole antenna. The default wire dipole is center fed with the feedpoint at the origin, and it is located along the Z-axis. The antenna length is chosen for an operating frequency of 75 MHz.

ant = wireStack(libant) converts a strip-based antenna from the Antenna Toolbox™ library to a wire antenna for further analysis. Conversion is based on the equivalent radius using the strip2cylinder utility function.

Input Arguments

libant — Antenna elements

antenna element object

Antenna elements, specified as any one of the following antenna element objects: dipole, dipoleFolded, dipoleMeander, dipoleVee, dipoleHelix, dipoleJ, dipoleCycloid, dipoleCrossed, loopCircular, and loopRectangular.

Output Arguments

ant — Wire antenna

wireStack object (default)

Wire antenna, returned as a wireStack object.

Properties

Name — Name of wire antenna

'Dipole' (default) | string scalar

Name of the wire antenna, specified as a string scalar.

Example: ant.Name = 'monopole'

Data Types: string

FeedLocation — Antenna feed locations

[0 0 0] (default) | N-by-3 array of Cartesian coordinates

This property is read-only.

Antenna feed locations, specified as an N-by-3 array of Cartesian coordinates with each element unit in meters.

Example: ant.FeedLocation = [0 2 4]

Data Types: double

FeedVoltage — Magnitude of excitation voltage at each feed

1 (default) | 1-by-N array of doubles

Magnitude of excitation voltage at each feed, specified as a 1-by-N array of doubles.

Example: ant.FeedVoltage = 2

Data Types: double

FeedPhase — Phase shift applied to voltage at each feed

0 (default) | 1-by-M array of doubles

Phase shift applied to voltage at each feed, specified as a 1-by-M array of doubles.

Example: ant.FeedVoltage = 60

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
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
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

Examples

Default Wire Antenna

Create and view a default dipole wire antenna.

ant = wireStack

ant = 
  wireStack with properties:

            Name: 'Dipole'
    FeedLocation: [0 0 0]
     FeedVoltage: 1
       FeedPhase: 0
            Tilt: 0
        TiltAxis: [1 0 0]

show(ant)

Plot the radiation pattern of the antenna at the specified frequency.

pattern(ant,75e6)

Circular Loop Wire Antenna

Create and view a circular loop wire antenna.

ant = loopCircular('Radius',0.075,'Thickness',0.0005);
wireant = wireStack(ant)

wireant = 
  wireStack with properties:

            Name: 'Circular loop'
    FeedLocation: [3.1745e-16 0.0747 0]
     FeedVoltage: 1
       FeedPhase: 0
            Tilt: 0
        TiltAxis: [1 0 0]

show(wireant)

Plot the directivity pattern of the antenna at 1 GHz.

pattern(wireant,1e9);

Version History

Introduced in R2020a