dipoleCycloid

Create cycloid dipole antenna

Description

The dipoleCycloid object is a half-wavelength cycloid dipole antenna. For the default cycloid dipole, the feed point is on the loop section. The default length is for an operating frequency of 48 MHz.

The width of the dipole is related to the circular cross-section by the equation

$$w=2d=4r$$

, where:

• d is the diameter of equivalent cylindrical pole

• r is the radius of equivalent cylindrical pole

For a given cylinder radius, use the cylinder2strip utility function to calculate the equivalent width.

Creation

Syntax

dc = dipoleCycloid

dc = dipoleCycloid(Name,Value)

Description

dc = dipoleCycloid creates a half-wavelength cycloid dipole antenna oriented along Z-axis.

dc = dipoleCycloid(Name,Value) creates a half-wavelength cycloid dipole antenna, with additional properties specified by one or more name-value pair arguments. Name is the property name and Value is the corresponding value. You can specify several name-value pair arguments in any order as Name1, Value1, ..., NameN, ValueN. Properties not specified retain their default values.

Properties

Length — Dipole length along z-axis

1.2200 (default) | scalar

Dipole length along z-axis, specified as a scalar in meters. By default, the length is for an operating frequency of 48 MHz.

Example: 'Length',0.9

Data Types: double

Width — Dipole width

0.0508 (default) | scalar

Dipole width, specified as a scalar in meters.

Example: 'Width',0.09

Data Types: double

LoopRadius — Circular loop radius in xy- plane

0.3100 (default) | scalar

Circular loop radius in xy- plane, specified as a scalar in meters.

Example: 'LoopRadius',0.500

Data Types: double

Gap — Gap of loop in xy- plane

0.0400 (default) | scalar

Gap of loop in xy- plane, specified as a scalar in meters.

Example: 'Gap',0.006

Data Types: double

Conductor — Type of metal material

'PEC' (default) | metal object

Type of the metal used as a conductor, specified as a 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: m = metal('Copper'); 'Conductor',m

Example: m = metal('Copper'); ant.Conductor = m

Load — Lumped elements

[1x1 LumpedElement] (default) | lumped element object

Lumped elements added to the antenna feed, specified as the comma-separated pair consisting of 'Load' and a lumped element object. For more information, see lumpedElement.

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

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

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
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
design	Design prototype antenna or arrays for resonance around specified frequency
efficiency	Radiation efficiency of antenna
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
optimize	Optimize antenna or array using SADEA optimizer
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
rcs	Calculate and plot radar cross section (RCS) of platform, 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 Cycloid Dipole

Create a default cycloid dipole antenna using the dipoleCycloid object and view it.

dc = dipoleCycloid

dc = 
  dipoleCycloid with properties:

        Length: 1.2200
         Width: 0.0508
    LoopRadius: 0.3100
           Gap: 0.0400
     Conductor: [1x1 metal]
          Tilt: 0
      TiltAxis: [1 0 0]
          Load: [1x1 lumpedElement]

show(dc)

Impedance of Cycloid Dipole

Calculate the impedance of a cycloid dipole of width, 0.05 m, over a frequency span of 50 MHz - 100 MHz.

d = dipoleCycloid('Width',0.05);
impedance(d,linspace(50e6,100e6,51))

Radiation Pattern of Cycloid Dipole

Plot the radiation pattern of a cycloid dipole of width,0.05 m, at a frequency of 48 MHz.

d = dipoleCycloid('Width',0.05)

d = 
  dipoleCycloid with properties:

        Length: 1.2200
         Width: 0.0500
    LoopRadius: 0.3100
           Gap: 0.0400
     Conductor: [1x1 metal]
          Tilt: 0
      TiltAxis: [1 0 0]
          Load: [1x1 lumpedElement]

pattern(d,48e6)

References

[1] Balanis, C.A. Antenna Theory: Analysis and Design. 3rd Ed. New York: Wiley, 2005.

[2] Volakis, John. Antenna Engineering Handbook. 4th Ed. New York: McGraw-Hill, 2007.

Version History

Introduced in R2017a