monopoleCylindrical

Create cylindrical monopole antenna over rectangular ground plane

    Description

    The monopoleCylindrical object is a cylindrical monopole antenna mounted over a rectangular ground plane. This antenna is useful for designing thicker monopole antennas. These antennas are mostly used in wireless mobile communication due to their broadband characteristics and simple design.

    Cylindrical monopole antenna geometry, default radiation pattern, and impedance plot.

    Creation

    Description

    example

    ant = monopoleCylindrical creates a cylindrical monopole antenna object with default dimensions for an operating frequency of 70 MHz.

    example

    ant = monopoleCylindrical(Name,Value) sets Properties using one or more name-value pairs. For example, ant = monopoleCylindrical('Radius',0.04), creates a cylindrical monopole antenna with a radius of 0.04 meters.

    Properties

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    Height of the monopole along the z-axis, specified as a positive scalar in meters.

    Example: 'Height',3

    Data Types: double

    Radius of the monopole, specified as a positive scalar in meters.

    Example: 'Radius',0.05

    Data Types: double

    Ground plane length along x-axis, specified as a positive scalar in meters.

    Example: 'GroundPlaneLength',4

    Data Types: double

    Ground plane width along y-axis, specified as a positive scalar in meters.

    Example: 'GroundPlaneWidth',2.5

    Data Types: double

    Signed distance from the center along the length and the width of the ground plane, specified as a two-element vector in meters.

    Example: 'FeedOffset',[2 1]

    Data Types: double

    Determine if the monopole top is closed with a cap or left open, specified as 0 or 1. Specify 1 for a closed-top monopole, and 0 for an open-top monopole.

    Example: 'ClosedEnd',1

    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: m = metal('Copper'); 'Conductor',m

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

    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.

    Data Types: double

    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'

    Data Types: double

    Lumped elements added to the antenna feed, specified as a lumpedElement object handle. 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: 'Load',lumpedelement, where lumpedelement is the load added to the antenna feed.

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

    Object Functions

    showDisplay antenna or array structure; display shape as filled patch
    axialRatioAxial ratio of antenna
    beamwidthBeamwidth of antenna
    chargeCharge distribution on metal or dielectric antenna or array surface
    currentCurrent distribution on metal or dielectric antenna or array surface
    cylinder2stripCylinder equivalent width approximation
    designDesign prototype antenna or arrays for resonance at specified frequency
    efficiencyRadiation efficiency of antenna
    EHfieldsElectric and magnetic fields of antennas; Embedded electric and magnetic fields of antenna element in arrays
    impedanceInput impedance of antenna; scan impedance of array
    meshMesh properties of metal or dielectric antenna or array structure
    meshconfigChange mesh mode of antenna structure
    optimizeOptimize antenna or array using SADEA optimizer
    patternRadiation pattern and phase of antenna or array; Embedded pattern of antenna element in array
    patternAzimuthAzimuth pattern of antenna or array
    patternElevationElevation pattern of antenna or array
    rcsCalculate and plot radar cross section (RCS) of platform, antenna, or array
    returnLossReturn loss of antenna; scan return loss of array
    sparametersS-parameter object
    strip2cylinderCalculates equivalent radius approximation for strip
    vswrVoltage standing wave ratio of antenna

    Examples

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    Create a cylindrical monopole antenna with default properties.

    ant = monopoleCylindrical
    ant = 
      monopoleCylindrical with properties:
    
                   Height: 1
                   Radius: 0.0400
        GroundPlaneLength: 2
         GroundPlaneWidth: 2
               FeedOffset: [0 0]
                ClosedEnd: 0
                Conductor: [1x1 metal]
                     Tilt: 0
                 TiltAxis: [1 0 0]
                     Load: [1x1 lumpedElement]
    
    

    View the antenna using the show function.

    show(ant)

    Figure contains an axes. The axes with title monopoleCylindrical antenna element contains 4 objects of type patch, surface. These objects represent PEC, feed.

    Plot the radiation pattern of cylindrical monopole antenna at a frequency of 70 MHz.

    pattern(ant,70e6)

    Figure contains an axes and other objects of type uicontrol. The axes contains 4 objects of type patch, surface.

    Create a cylindrical monopole antenna with length and radius as 1 m and 50 mm respectively.

    ant = monopoleCylindrical;
    ant.Height = 1;
    ant.Radius = 50e-3
    ant = 
      monopoleCylindrical with properties:
    
                   Height: 1
                   Radius: 0.0500
        GroundPlaneLength: 2
         GroundPlaneWidth: 2
               FeedOffset: [0 0]
                ClosedEnd: 0
                Conductor: [1x1 metal]
                     Tilt: 0
                 TiltAxis: [1 0 0]
                     Load: [1x1 lumpedElement]
    
    

    Visualize the antenna using show function.

    show(ant)

    Figure contains an axes. The axes with title monopoleCylindrical antenna element contains 4 objects of type patch, surface. These objects represent PEC, feed.

    Plot the S-parameters over a frequency range of 30 MHz to 120 MHz.

    s = sparameters(ant,linspace(30e6,120e6,51));
    rfplot(s)

    Figure contains an axes. The axes contains an object of type line. This object represents dB(S_{11}).

    Create cylindrical monopole antennas with an open-ended top and a closed-ended top respectively.

    ant = monopoleCylindrical("Radius",0.1);
    ant_ClosedEnded = monopoleCylindrical("Radius",0.1,"ClosedEnd",1);

    Calculate and plot the current distribution for a cylindrical monopole antennas at 70 MHz frequency.

    I_OpenEnded = current(ant,70e6)
    I_OpenEnded = 3×334 complex
    
      -0.0105 + 0.0033i  -0.0001 + 0.0000i   0.0063 - 0.0024i  -0.0008 + 0.0004i   0.0222 - 0.0056i  -0.0013 + 0.0005i  -0.0575 + 0.0053i  -0.0037 + 0.0017i   0.0013 - 0.0005i   0.0120 - 0.0039i   0.0005 - 0.0002i   0.0111 - 0.0034i   0.0083 - 0.0029i  -0.0346 + 0.0034i  -0.0021 + 0.0010i  -0.0108 + 0.0034i  -0.0129 + 0.0033i  -0.0011 + 0.0002i  -0.0007 + 0.0003i  -0.0061 + 0.0023i   0.0038 - 0.0010i  -0.0034 + 0.0011i  -0.0064 + 0.0023i  -0.0059 + 0.0022i  -0.0040 + 0.0019i  -0.0226 + 0.0061i  -0.0216 + 0.0059i  -0.0084 + 0.0029i   0.0022 - 0.0012i  -0.0383 + 0.0074i  -0.0084 + 0.0029i  -0.0034 + 0.0017i   0.0224 - 0.0061i   0.0582 - 0.0050i   0.0155 - 0.0042i  -0.0137 + 0.0044i   0.0008 + 0.0003i  -0.0140 + 0.0043i   0.0580 - 0.0052i  -0.0367 + 0.0032i   0.0008 - 0.0004i   0.0312 - 0.0062i   0.0007 - 0.0003i   0.0123 - 0.0020i   0.0032 - 0.0014i   0.0009 - 0.0005i  -0.0112 + 0.0037i  -0.0037 + 0.0017i   0.0019 - 0.0007i  -0.0002 - 0.0002i
       0.0096 - 0.0028i   0.0053 - 0.0020i   0.0030 - 0.0013i   0.0039 - 0.0019i   0.0073 - 0.0018i   0.0084 - 0.0030i   0.0207 - 0.0015i   0.0007 - 0.0003i   0.0081 - 0.0029i   0.0054 - 0.0018i   0.0247 - 0.0062i   0.0081 - 0.0025i   0.0027 - 0.0009i   0.0505 - 0.0044i   0.0034 - 0.0017i  -0.0084 + 0.0025i  -0.0189 + 0.0048i  -0.0240 + 0.0061i  -0.0037 + 0.0017i  -0.0065 + 0.0023i   0.0246 - 0.0065i   0.0085 - 0.0030i   0.0061 - 0.0023i   0.0062 - 0.0022i   0.0008 - 0.0004i  -0.0061 + 0.0017i   0.0059 - 0.0017i   0.0026 - 0.0009i  -0.0009 + 0.0005i   0.0003 + 0.0001i  -0.0027 + 0.0009i   0.0021 - 0.0010i   0.0058 - 0.0016i   0.0181 - 0.0018i  -0.0174 + 0.0047i  -0.0001 + 0.0000i   0.0620 - 0.0054i   0.0007 - 0.0002i  -0.0187 + 0.0014i  -0.0496 + 0.0046i  -0.0039 + 0.0019i  -0.0227 + 0.0040i   0.0037 - 0.0017i   0.0374 - 0.0072i   0.0039 - 0.0018i   0.0022 - 0.0011i   0.0044 - 0.0016i  -0.0007 + 0.0003i   0.0084 - 0.0029i  -0.0619 + 0.0056i
       0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
    
    
    current(ant,70e6)

    Figure contains an axes. The axes with title Current distribution contains 4 objects of type patch.

    I_ClosedEnded = current(ant_ClosedEnded,70e6)
    I_ClosedEnded = 3×342 complex
    
      -0.0095 + 0.0039i  -0.0001 + 0.0000i   0.0057 - 0.0027i  -0.0007 + 0.0004i   0.0201 - 0.0069i  -0.0012 + 0.0006i  -0.0522 + 0.0084i  -0.0034 + 0.0019i   0.0012 - 0.0006i   0.0109 - 0.0045i   0.0005 - 0.0003i   0.0101 - 0.0041i   0.0076 - 0.0034i  -0.0314 + 0.0053i  -0.0019 + 0.0011i  -0.0098 + 0.0040i  -0.0117 + 0.0041i  -0.0010 + 0.0003i  -0.0006 + 0.0003i  -0.0056 + 0.0026i   0.0035 - 0.0012i  -0.0031 + 0.0013i  -0.0059 + 0.0026i  -0.0054 + 0.0025i  -0.0036 + 0.0021i  -0.0206 + 0.0074i  -0.0197 + 0.0071i  -0.0076 + 0.0034i   0.0020 - 0.0013i  -0.0348 + 0.0095i  -0.0076 + 0.0034i  -0.0031 + 0.0019i   0.0204 - 0.0073i   0.0528 - 0.0082i   0.0141 - 0.0050i  -0.0125 + 0.0052i   0.0007 + 0.0003i  -0.0127 + 0.0050i   0.0526 - 0.0084i  -0.0333 + 0.0052i   0.0007 - 0.0004i   0.0283 - 0.0079i   0.0006 - 0.0003i   0.0112 - 0.0027i   0.0029 - 0.0016i   0.0008 - 0.0005i  -0.0102 + 0.0043i  -0.0034 + 0.0019i   0.0018 - 0.0008i  -0.0002 - 0.0002i
       0.0087 - 0.0034i   0.0048 - 0.0023i   0.0028 - 0.0014i   0.0036 - 0.0021i   0.0067 - 0.0022i   0.0076 - 0.0035i   0.0188 - 0.0026i   0.0006 - 0.0003i   0.0073 - 0.0034i   0.0049 - 0.0021i   0.0225 - 0.0075i   0.0074 - 0.0029i   0.0024 - 0.0011i   0.0458 - 0.0071i   0.0031 - 0.0019i  -0.0077 + 0.0030i  -0.0171 + 0.0058i  -0.0218 + 0.0074i  -0.0034 + 0.0019i  -0.0059 + 0.0027i   0.0224 - 0.0079i   0.0078 - 0.0034i   0.0056 - 0.0026i   0.0056 - 0.0025i   0.0007 - 0.0004i  -0.0055 + 0.0020i   0.0054 - 0.0020i   0.0023 - 0.0010i  -0.0008 + 0.0005i   0.0003 + 0.0001i  -0.0024 + 0.0011i   0.0019 - 0.0011i   0.0053 - 0.0019i   0.0164 - 0.0027i  -0.0158 + 0.0057i  -0.0001 + 0.0000i   0.0563 - 0.0089i   0.0006 - 0.0002i  -0.0170 + 0.0024i  -0.0450 + 0.0074i  -0.0036 + 0.0021i  -0.0206 + 0.0053i   0.0033 - 0.0019i   0.0340 - 0.0092i   0.0035 - 0.0021i   0.0020 - 0.0013i   0.0040 - 0.0018i  -0.0006 + 0.0003i   0.0077 - 0.0034i  -0.0562 + 0.0090i
       0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
    
    
    figure;
    current(ant_ClosedEnded,70e6)

    Figure contains an axes. The axes with title Current distribution contains 4 objects of type patch.

    More About

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    References

    [1] King, Ronald W.P. Characteristics of Cylindrical Dipoles and Monopoles. Boston, MA: Springer, 1971.

    Introduced in R2021a