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rhombic

Create a rhombic antenna

Since R2020b

Description

The default rhombic object creates a rhombic antenna resonating around 510 MHz. It consists of a rhombus with a feed at one acute angles and a termination resistor at the other acute angle. It has a simple design and is highly directional. These antennas are used in shortwave radio broadcasting and point-to-point communications.

Creation

Description

ant = rhombic creates a rhombic antenna with default property values. The default dimensions are chosen for an operating frequency of around 510 MHz. The default rhombic antenna is fed at one acute angle and the other acute angle is terminated with a load of 500 ohms.

example

ant = rhombic(PropertyName=Value) sets properties using one or more name-value arguments. PropertyName is the property name and Value is the corresponding value. You can specify several name-value arguments in any order as PropertyName1=Value1,...,PropertyNameN=ValueN. Properties that you do not specify, retain their default values.

For example, ant = rhombic(ArmLength=3) creates a rhombic antenna with an arm of length 3 meters.

Properties

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Length of each of the rhombus, specified as a scalar in meters.

Example: 4

Data Types: double

The acute angle between the adjacent arms at the feed location, specified as a scalar in degrees.

Example: 40

Data Types: double

Width of the arm of the rhombus, specified as a scalar in meters.

Example: 0.3

Data Types: double

Type of the metal used as a conductor, specified as a metal object. You can choose any metal from the MetalCatalog or specify a metal of your choice. For more information on metal conductor meshing, see Meshing.

Example: metal("Copper")

Lumped elements added to the antenna feed, specified as a lumpedElement object. You can add a load anywhere on the surface of the antenna. By default, the load is at the feed.

Example: lumpedElement(Impedance=75)

Tilt angle of the antenna in degrees, specified as a scalar or vector. For more information, see Rotate Antennas and Arrays.

Example: 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.

Data Types: double

Tilt axis of the antenna, specified as one of these values:

  • 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, specified as a 2-by-3 matrix corresponding to two three-element vectors of Cartesian coordinates. In this case, the antenna rotates around the line joining the two points.

  • "x", "y", or "z" to describe a rotation about the x-, y-, or z-axis, respectively.

For more information, see Rotate Antennas and Arrays.

Example: [0 1 0]

Example: [0 0 0;0 1 0]

Example: "Z"

Data Types: double | string

Object Functions

axialRatioCalculate and plot axial ratio of antenna or array
bandwidthCalculate and plot absolute bandwidth of antenna or array
beamwidthBeamwidth of antenna
chargeCharge distribution on antenna or array surface
currentCurrent distribution on antenna or array surface
designCreate antenna, array, or AI-based antenna resonating at specified frequency
efficiencyCalculate and plot radiation efficiency of antenna or array
EHfieldsElectric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays
feedCurrentCalculate current at feed for antenna or array
impedanceCalculate and plot input impedance of antenna or scan impedance of array
infoDisplay information about antenna, array, or platform
memoryEstimateEstimate memory required to solve antenna or array mesh
meshGenerate and view mesh for antennas, arrays, and custom shapes
meshconfigChange meshing mode of antenna, array, custom antenna, custom array, or custom geometry
msiwriteWrite antenna or array analysis data to MSI planet file
optimizeOptimize antenna and array catalog elements using SADEA or TR-SADEA algorithm
patternPlot radiation pattern of antenna, array, or embedded element of array
patternAzimuthAzimuth plane radiation pattern of antenna or array
patternElevationElevation plane radiation pattern of antenna or array
peakRadiationCalculate and mark maximum radiation points of antenna or array on radiation pattern
rcsCalculate and plot monostatic and bistatic radar cross section (RCS) of platform, antenna, or array
resonantFrequencyCalculate and plot resonant frequency of antenna
returnLossCalculate and plot return loss of antenna or scan return loss of array
showDisplay antenna, array structures, shapes, or platform
sparametersCalculate S-parameters for antenna or array
stlwriteWrite mesh information to STL file
vswrCalculate and plot voltage standing wave ratio (VSWR) of antenna or array element

Examples

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Create a default rhombic antenna.

ant = rhombic
ant = 
  rhombic with properties:

       ArmLength: 2
    ArmElevation: 20
           Width: 0.1000
       Conductor: [1×1 metal]
            Tilt: 0
        TiltAxis: [1 0 0]
            Load: [1×1 lumpedElement]

View the antenna using the show function.

show(ant);

Figure contains an axes object. The axes object with title rhombic antenna element, xlabel x (m), ylabel y (m) contains 4 objects of type patch, surface. These objects represent PEC, feed, load.

Plot the radiation pattern of the antenna at 510 MHz.

pattern(ant, 510e6);

Figure contains 2 axes objects and other objects of type uicontrol. Axes object 1 contains 3 objects of type patch, surface. Hidden axes object 2 contains 17 objects of type surface, line, text, patch.

References

[1] Decker, R. “The Influence of Gain and Current Attenuation on the Design of the Rhombic Antenna.” IRE Transactions on Antennas and Propagation 7, no. 2 (April 1959): 188–196.

Version History

Introduced in R2020b