reflectorParabolic

Create parabolic reflector antenna

Description

The reflectorParabolic object creates a parabolic reflector antenna. Parabolic reflector antennas are electrically large structures and are at least 10 wavelengths in diameter. These reflectors are used in TV antennas and satellite communications, for example.

Creation

Syntax

ant = reflectorParabolic

ant = reflectorParabolic(Name,Value)

Description

ant = reflectorParabolic creates a dipole-fed parabolic reflector antenna. The default antenna exciter operates at 10 GHz. The reflector is 10λ in diameter, where λ corresponds to the value of wavelength.

ant = reflectorParabolic(Name,Value) sets properties using one or more name-value pairs. For example, ant = reflectorParabolic('FocalLength',0.5) creates a parabolic reflector antenna of focal length 0.5 meters.

Properties

Exciter — Antenna or array type used as exciter

dipole (default) | antenna object | array object

Antenna type used as an exciter, specified as any single-element antenna object. Except reflector and cavity antenna elements, you can use any of the antenna elements or array elements in the Antenna Toolbox™ as an exciter.

Example: 'Exciter',horn

Example: ant.Exciter = horn

Example: ant.Exciter = linearArray('patchMicrostrip')

Radius — Radius of parabolic reflector

0.1500 (default) | positive scalar integer

Radius of the parabolic reflector, specified as a positive scalar integer in meters.

Example: 'Radius',0.22

Example: ant.Radius = 0.22

Data Types: double

FocalLength — Focal length of parabolic dish

0.0750 (default) | positive scalar integer

Focal length of the parabolic dish, specified as a positive scalar integer in meters.

Example: 'FocalLength',0.0850

Example: ant.FocalLength = 0.0850

Data Types: double

FeedOffset — Signed distance from focus

[0 0 0] (default) | three-element vector

Signed distance from the focus of the parabolic dish, specified as a three-element vector in meters. By default, the antenna exciter is at the focus of the parabola. Using the FeedOffset property, you can place the exciter anywhere on the parabola.

Example: 'FeedOffset',[0.0850 0 0]

Example: ant.FeedOffset = [0.0850 0 0]

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 a lumped element object. For more information, see lumpedElement.

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

Example: ant.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: ant.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: ant.TiltAxis = 'Z'

Note

The wireStack antenna object only accepts the dot method to change its properties.

Data Types: double

SolverType — Solver for antenna analysis

'MoM-PO' (default) | 'MoM' | 'FMM'

Solver for antenna analysis, specified as the comma-separated pair consisting of 'SolverType' and 'MoM-PO' or 'MoM' (Method of Moments) or 'FMM' (Fast Multipole Method).

Example: 'SolverType','MOM'

Data Types: char

Object Functions

show	Display antenna or array structure; display shape as filled patch
solver	Access FMM solver for electromagnetic analysis
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 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 or 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 Parabolic Reflector and Radiation Pattern

Create and view a default parabolic reflector antenna.

ant = reflectorParabolic

ant = 
  reflectorParabolic with properties:

        Exciter: [1x1 dipole]
         Radius: 0.1500
    FocalLength: 0.0750
     FeedOffset: [0 0 0]
           Tilt: 0
       TiltAxis: [1 0 0]
           Load: [1x1 lumpedElement]
     SolverType: 'MoM-PO'

show(ant)

Plot the radiation pattern of the parabolic reflector at 10 GHz.

pattern(ant,10e9)

Create Parabolic Reflector-Backed Circular Array of Equiangular Spiral Antenna

Create a circular array of equiangular spiral antennas.

circA = circularArray('Element',spiralEquiangular,'Radius',0.1);

Create a parabolic reflector-backed antenna.

ant = reflectorParabolic('Exciter',circA)

ant = 
  reflectorParabolic with properties:

        Exciter: [1x1 circularArray]
         Radius: 0.1500
    FocalLength: 0.0750
     FeedOffset: [0 0 0]
           Tilt: 0
       TiltAxis: [1 0 0]
           Load: [1x1 lumpedElement]
     SolverType: 'MoM-PO'

show(ant)

Version History

Introduced in R2018b