patchMicrostripCircular

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

Description

Use the default patchMicrostripCircular object to create a probe-fed circular microstrip patch antenna resonating around 1 GHz. 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.

Creation

Syntax

circularpatch = patchMicrostripCircular

circularpatch = patchMicrostripCircular(Name=Value)

Description

circularpatch = patchMicrostripCircular creates a probe-fed circular microstrip patch antenna with default property values. The default dimensions are chosen for an operating frequency of around 1 GHz.

circularpatch = patchMicrostripCircular(Name=Value)sets 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

Radius — Patch radius

0.0798 (default) | positive scalar | tunable for patchMicrostripCircular type AIAntenna

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 — Height of patch

0.0060 (default) | positive scalar | tunable for patchMicrostripCircular type AIAntenna

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

GroundPlaneLength — Ground plane length

0.3000 (default) | positive scalar

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

GroundPlaneWidth — Ground plane width

0.3000 (default) | positive scalar

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

Substrate — Type of dielectric material

dielectric("Air") (default) | dielectric object

Type of dielectric material used as a substrate, specified as a dielectric object. You can choose any dielectric material from the DielectricCatalog or specify a dielectric material of your choice. The substrate dimensions must be equal to the ground plane dimensions. For more information on dielectric substrate meshing, see Meshing.

Note

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

Example: Substrate=dielectric("FR4")

Example: antenna.Substrate = dielectric("FR4")

PatchCenterOffset — Signed distance from center along length and width of ground plane

[0 0] (default) | two-element real vector

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

FeedOffset — Signed distance from center along length and width of ground plane

[–0.0525 0] (default) | two-element real vector

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

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: metal("Copper")

Load — Lumped elements

[1x1 lumpedElement] (default) | lumpedElement object

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: Load=lumpedElement(Impedance=75)

Example: antenna.Load = lumpedElement(Impedance=75)

Tilt — Tilt angle of antenna

0 (default) | scalar | vector

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

TiltAxis — Tilt axis of antenna

[1 0 0] (default) | three-element vector | 2-by-3 matrix | "X" | "Y" | "Z"

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

axialRatio	Calculate and plot axial ratio of antenna or array
bandwidth	Calculate and plot absolute bandwidth of antenna or array
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 or create AI-based antenna from antenna catalog objects
efficiency	Calculate and plot radiation efficiency of antenna or array
EHfields	Electric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays
feedCurrent	Calculate current at feed for antenna or array
impedance	Calculate and plot input impedance of antenna or scan impedance of array
info	Display information about antenna, array, or platform
memoryEstimate	Estimate memory required to solve antenna or array mesh
mesh	Mesh properties of metal, dielectric antenna, or array structure
meshconfig	Change meshing mode of antenna, array, custom antenna, custom array, or custom geometry
msiwrite	Write antenna or array analysis data to MSI planet file
optimize	Optimize antenna or array using SADEA optimizer
pattern	Plot radiation pattern and phase of antenna or array or embedded pattern of antenna element in array
patternAzimuth	Azimuth plane radiation pattern of antenna or array
patternElevation	Elevation plane radiation pattern of antenna or array
peakRadiation	Calculate and mark maximum radiation points of antenna or array on radiation pattern
rcs	Calculate and plot monostatic and bistatic radar cross section (RCS) of platform, antenna, or array
resonantFrequency	Calculate and plot resonant frequency of antenna
returnLoss	Calculate and plot return loss of antenna or scan return loss of array
show	Display antenna, array structures, shapes, or platform
sparameters	Calculate S-parameters for antenna or array
stlwrite	Write mesh information to STL file
vswr	Calculate and plot voltage standing wave ratio (VSWR) of antenna or array element

Examples

Circular Microstrip Patch

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)

Radiation Pattern and Impedance of Circular Microstrip Patch

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)   

Plot the pattern of the patch antenna at 1GHz.

pattern(cp,1e9);

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);

Create AI Model Based Circular Microstrip Patch Antenna

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: 0.0814
                    Height: 0.0084

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

Vary its radius and height and calculate its resonant frequency.

pAI.Radius = 0.081;
pAI.Height = 0.0075;
resonantFrequency(pAI)

ans = 
1.0008e+09

Convert the AIAntenna to a regular circular microstrip patch antenna.

pmC = exportAntenna(pAI)

pmC = 
  patchMicrostripCircular with properties:

               Radius: 0.0810
               Height: 0.0075
            Substrate: [1x1 dielectric]
    GroundPlaneLength: 0.3038
     GroundPlaneWidth: 0.3038
    PatchCenterOffset: [0 0]
           FeedOffset: [-0.0095 0.0365]
            Conductor: [1x1 metal]
                 Tilt: 0
             TiltAxis: [1 0 0]
                 Load: [1x1 lumpedElement]

Version History

Introduced in R2017b

R2023b: AI model based antenna analysis

Design, tune, and analyze this antenna using an AI model. Using AI-based antenna models over conventional full-wave solvers significantly reduces the simulation time required to fine-tune the antenna to meet your design goals. Set the ForAI argument in the design function to true to create a patchMicrostripCircular type AIAntenna. To use this feature, you need license to the Statistics and Machine Learning Toolbox™ in addition to the Antenna Toolbox™.