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patchMicrostripCircular

Create regular or AI-based probe-fed circular microstrip patch antenna

Description

Use the patchMicrostripCircular object to create a probe-fed circular microstrip patch antenna. By default, the patch is centered at the origin with feed point along the radius and the ground plane on the xy- plane at z = 0.

Circular microstrip antennas are used as low-profile antennas in airborne and spacecraft applications. These antennas also find use in portable wireless applications because they are lightweight, low cost, and easily manufacturable.

You can perform full-wave EM solver based analysis on the regular patchMicrostripCircular antenna or you can create a patchMicrostripCircular type AIAntenna and explore the design space to tune the antenna for your application using AI-based analysis.

Circular microstrip patch antenna

Creation

Description

example

circularpatch = patchMicrostripCircular creates a probe-fed circular microstrip patch antenna.

example

circularpatch = patchMicrostripCircular(Name=Value) sets additional Properties using one or more name-value arguments. Name is the property name and Value is the corresponding value. You can specify several name-value arguments in any order as Name1=Value1, ..., NameN=ValueN. Properties that you do not specify retain their default values.

For example, circularpatch = patchMicrostripCircular(Radius=0.2) creates a circular patch of radius 0.2 m.

  • You can also create a patchMicrostripCircular antenna resonating at a desired frequency using the design function.

  • You can also create a patchMicrostripCircular antenna from a microstrip patch type AIAntenna object using the exportAntenna function.

  • A patchMicrostripCircular type AIAntenna has some common tunable properties with a regular patchMicrostripCircular antenna for AI-based analysis. Other properties of the regular patchMicrostripCircular antenna are retained as read-only in its AIAntenna equivalent. To find the upper and lower bounds of the tunable properties, use tunableRanges function.

Properties

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Patch radius, specified as a scalar in meters. The default radius is for an operating frequency of 1 GHz. This property is tunable for patchMicrostripCircular type AIAntenna object created using the design function.

Example: 0.2

Data Types: double

Height of patch above the ground plane along the z-axis, specified as a scalar in meters. This property is tunable for patchMicrostripCircular type AIAntenna object created using the design function.

Example: 0.001

Data Types: double

Ground plane length along the x-axis, specified as a scalar in meters. Setting 'GroundPlaneLength' to Inf, uses the infinite ground plane technique for antenna analysis.

Example: 120e-3

Data Types: double

Ground plane width along the y-axis, specified as a scalar in meters. Setting 'GroundPlaneWidth' to Inf, uses the infinite ground plane technique for antenna analysis.

Example: 120e-3

Data Types: double

Type of dielectric material used as a substrate, specified as a dielectric material object. You can choose any material from the DielectricCatalog or use your own dielectric material. For more information, see dielectric. For more information on dielectric substrate meshing, see Meshing.

Note

The substrate dimensions must be less than the ground plane dimensions.

Example: dielectric("FR4")

Signed distance from center along length and width of ground plane, specified as a two-element real vector with each element unit in meters. Use this property to adjust the location of the patch relative to the ground plane.

Example: [0.01 0.01]

Data Types: double

Signed distance from center along length and width of ground plane, specified as a two-element real vector with each element unit in meters. Use this property to adjust the location of the feedpoint relative to the ground plane and patch.

Example: [0.01 0.01]

Data Types: double

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: 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. For more information, see lumpedElement.

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

showDisplay antenna, array structures, shapes, or platform
axialRatioAxial ratio of antenna
beamwidthBeamwidth of antenna
chargeCharge distribution on antenna or array surface
currentCurrent distribution on antenna or array surface
designDesign prototype antenna or arrays for resonance around specified frequency or create AI-based antenna from antenna catalog objects
efficiencyRadiation efficiency of antenna
EHfieldsElectric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays
impedanceInput impedance of antenna or scan impedance of array
meshMesh properties of metal, dielectric antenna, or array structure
meshconfigChange meshing mode of antenna, array, custom antenna, custom array, or custom geometry
optimizeOptimize antenna or array using SADEA optimizer
patternPlot radiation pattern and phase of antenna or array or embedded pattern of antenna element in array
patternAzimuthAzimuth plane radiation pattern of antenna or array
patternElevationElevation plane radiation pattern of antenna or array
rcsCalculate and plot radar cross section (RCS) of platform, antenna, or array
returnLossReturn loss of antenna or scan return loss of array
sparametersCalculate S-parameters for antennas and antenna arrays
vswrVoltage standing wave ratio (VSWR) of antenna or array element

Examples

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Create and view a default circular microstrip patch.

cp = patchMicrostripCircular
cp = 
  patchMicrostripCircular with properties:

               Radius: 0.0798
               Height: 0.0060
            Substrate: [1x1 dielectric]
    GroundPlaneLength: 0.3000
     GroundPlaneWidth: 0.3000
    PatchCenterOffset: [0 0]
           FeedOffset: [-0.0525 0]
            Conductor: [1x1 metal]
                 Tilt: 0
             TiltAxis: [1 0 0]
                 Load: [1x1 lumpedElement]

show(cp)

Figure contains an axes object. The axes object with title patchMicrostripCircular antenna element, xlabel x (mm), ylabel y (mm) contains 5 objects of type patch, surface. These objects represent PEC, feed.

Create a circular patch antenna using given values. Display the antenna.

cp = patchMicrostripCircular(Radius=0.0798, Height=6e-3,...
        GroundPlaneLength=0.3, GroundPlaneWidth=0.3,...
        FeedOffset=[-0.0525 0]);
show(cp)   

Figure contains an axes object. The axes object with title patchMicrostripCircular antenna element, xlabel x (mm), ylabel y (mm) contains 5 objects of type patch, surface. These objects represent PEC, feed.

Plot the pattern of the patch antenna at 1GHz.

pattern(cp,1e9);

Figure contains an axes object and other objects of type uicontrol. The axes object contains 5 objects of type patch, surface.

Calculate the impedance of the antenna over a frequency span of 0.5 GHz to 1.5 GHz.

f = linspace(0.5e9,1.5e9,61);
impedance(cp,f);

Figure contains an axes object. The axes object with title Impedance, xlabel Frequency (GHz), ylabel Impedance (ohms) contains 2 objects of type line. These objects represent Resistance, Reactance.

This example shows how to create an AI model based circular microstrip patch antenna at 1GHz and calculate its resonant frequency.

pAI = design(patchMicrostripCircular,1e9,ForAI=true)
pAI = 
  AIAntenna with properties:

   Antenna Info
               AntennaType: 'patchMicrostripCircular'
    InitialDesignFrequency: 1.0000e+09

   Tunable Parameters
                    Radius: 0.0884
                    Height: 0.0060

Use 'showReadOnlyProperties(pAI)' to show read-only properties

Vary its radius and height and calculate its resonant frequency.

pAI.Radius = 0.084;
pAI.Height = 0.006;
resonantFrequency(pAI)
ans = 1.0032e+09

Convert the AIAntenna to a regular circular microstrip patch antenna.

pmC = exportAntenna(pAI)
pmC = 
  patchMicrostripCircular with properties:

               Radius: 0.0840
               Height: 0.0060
            Substrate: [1x1 dielectric]
    GroundPlaneLength: 0.2998
     GroundPlaneWidth: 0.2998
    PatchCenterOffset: [0 0]
           FeedOffset: [-0.0442 0]
            Conductor: [1x1 metal]
                 Tilt: 0
             TiltAxis: [1 0 0]
                 Load: [1x1 lumpedElement]

Version History

Introduced in R2017b

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