Main Content

dipoleCylindrical

Create cylindrical dipole antenna

expand all in page

    Description

    ThedipoleCylindricalobject creates a cylindrical dipole antenna. The length of the cylindrical dipole corresponds to half of the wavelength at the operating frequency. These antennas are used in designing thicker dipole antennas. These antennas are mostly used in wireless communications due to their simple design.

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

    Creation

    Syntax

    ant = dipoleCylindrical
    ant = dipoleCylindrical(Name,Value)

    Description

    example

    ant= dipoleCylindricalcreates a cylindrical dipole antenna object with default dimensions for an operating frequency of 70 MHz. The default dipole is center fed, with the feedpoint at the origin located on they-zplane.

    example

    ant= dipoleCylindrical(Name,Value)setsPropertiesusing one or more name-value pairs. For example,ant = dipoleCylindrical('Radius',0.04)creates a cylindrical dipole antenna with radius of 0.04 meters.

    Properties

    expand all

    Length of the dipole, specified as a positive scalar in meters.

    Example:'Length',3

    Data Types:double

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

    Example:'Radius',0.05

    Data Types:double

    Signed distance from the center along Z-axis, specified as a real-valued scalar in meters.

    Example:'FeedOffset',-0.2

    Data Types:double

    Determine if the dipole ends are closed with a flat cap or left open, specified as0or1. Specify1for closed ends of the dipole and0for open ends.

    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 theMetalCatalogor specify a metal of your choice. For more information, seemetal. For more information on metal conductor meshing, seeMeshing.

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

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

    天线倾角,指定为一个标量or vector with each element unit in degrees. For more information, seeRotate 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, seeRotate 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 alumpedElementobject handle. You can add a load anywhere on the surface of the antenna. By default, the load is at the feed. For more information, seelumpedElement.

    Example:'Load',lumpedelement, wherelumpedelementis the load added to the antenna feed.

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

    Object Functions

    show Display antenna or array structure; display shape as filled patch
    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
    cylinder2strip 圆柱等效宽度近似
    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
    strip2cylinder Calculates equivalent radius approximation for strip
    vswr Voltage standing wave ratio of antenna

    Examples

    collapse all

    Open Live Script

    Create a cylindrical dipole antenna with default properties.

    ant = dipoleCylindrical
    ant = dipoleCylindrical with properties: Length: 2 Radius: 0.0250 FeedOffset: 0 ClosedEnd: 0 Conductor: [1x1 metal] Tilt: 0 TiltAxis: [1 0 0] Load: [1x1 lumpedElement]

    View the antenna using theshowfunction.

    show(ant)

    图包含一个坐标轴对象。坐标轴对象with title dipoleCylindrical antenna element contains 3 objects of type patch, surface. These objects represent PEC, feed.

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

    pattern(ant,70e6)

    Figure contains an axes object and other objects of type uicontrol. The axes object contains 3 objects of type patch, surface.

    Open Live Script

    Create a center-fed cylindrical dipole with a length of2m and a radius of0.06m.

    ant = dipoleCylindrical('Length',2,'Radius',0.06)
    ant = dipoleCylindrical with properties: Length: 2 Radius: 0.0600 FeedOffset: 0 ClosedEnd: 0 Conductor: [1x1 metal] Tilt: 0 TiltAxis: [1 0 0] Load: [1x1 lumpedElement]

    Plot the impedance over a frequency range of 50 MHz to 120 MHz.

    impedance(ant,linspace(50e6,120e6,51))

    图包含一个坐标轴对象。坐标轴对象with title Impedance contains 2 objects of type line. These objects represent Resistance, Reactance.

    Open Live Script

    Create a cylindrical dipole antenna with a open-ended top and closed-ended top respectively.

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

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

    I_OpenEnded = current(ant,70e6)
    I_OpenEnded =3×400 complex-0.0000 - 0.0002i -0.0000 - 0.0005i -0.0000 - 0.0007i -0.0000 - 0.0005i -0.0000 - 0.0002i 0.0000 + 0.0002i 0.0000 + 0.0005i 0.0000 + 0.0007i 0.0000 + 0.0005i 0.0000 + 0.0002i 0.0000 + 0.0003i 0.0000 + 0.0007i 0.0000 + 0.0009i 0.0000 + 0.0007i 0.0000 + 0.0003i -0.0000 - 0.0003i -0.0000 - 0.0007i -0.0000 - 0.0009i -0.0000 - 0.0007i -0.0000 - 0.0003i -0.0000 - 0.0001i -0.0000 - 0.0002i -0.0000 - 0.0002i -0.0000 - 0.0002i -0.0000 - 0.0001i 0.0000 + 0.0001i 0.0000 + 0.0002i 0.0000 + 0.0002i 0.0000 + 0.0002i 0.0000 + 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0001i 0.0001 + 0.0001i 0.0000 + 0.0001i 0.0000 + 0.0000i -0.0000 - 0.0000i -0.0000 - 0.0001i -0.0001 - 0.0001i -0.0000 - 0.0001i -0.0000 - 0.0000i -0.0000 - 0.0000i -0.0001 - 0.0001i -0.0001 - 0.0001i -0.0001 - 0.0001i -0.0000 - 0.0000i 0.0000 + 0.0000i 0.0001 + 0.0001i 0.0001 + 0.0001i 0.0001 + 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0006i 0.0000 + 0.0004i 0.0000 + 0.0000i -0.0000 - 0.0004i -0.0000 - 0.0006i -0.0000 - 0.0006i -0.0000 - 0.0004i 0.0000 + 0.0000i 0.0000 + 0.0004i 0.0000 + 0.0006i -0.0000 - 0.0008i -0.0000 - 0.0005i 0.0000 + 0.0000i 0.0000 + 0.0005i 0.0000 + 0.0008i 0.0000 + 0.0008i 0.0000 + 0.0005i 0.0000 + 0.0000i -0.0000 - 0.0005i -0.0000 - 0.0008i 0.0000 + 0.0002i 0.0000 + 0.0001i 0.0000 + 0.0000i -0.0000 - 0.0001i -0.0000 - 0.0002i -0.0000 - 0.0002i -0.0000 - 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0001i 0.0000 + 0.0002i -0.0001 - 0.0001i -0.0000 - 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0001i 0.0001 + 0.0001i 0.0001 + 0.0001i 0.0000 + 0.0001i 0.0000 + 0.0000i -0.0000 - 0.0001i -0.0001 - 0.0001i 0.0001 + 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0000i -0.0000 - 0.0000i -0.0001 - 0.0001i -0.0001 - 0.0001i -0.0000 - 0.0000i 0.0000 + 0.0000i 0.0000 + 0.0000i 0.0001 + 0.0001i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0191 - 0.0016i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0190 + 0.0033i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0189 + 0.0036i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0185 + 0.0046i -0.0183 + 0.0049i -0.0183 + 0.0049i -0.0183 + 0.0049i -0.0183 + 0.0049i -0.0183 + 0.0049i -0.0183 + 0.0049i -0.0183 + 0.0049i -0.0183 + 0.0049i -0.0183 + 0.0049i -0.0183 + 0.0049i
    current(ant,70e6)

    图包含一个坐标轴对象。坐标轴对象with title Current distribution contains 3 objects of type patch.

    I_ClosedEnded = current(ant_ClosedEnded,70e6)
    I_ClosedEnded =3×428 complex-0.0000 - 0.0002i -0.0000 - 0.0005i -0.0000 - 0.0007i -0.0000 - 0.0005i -0.0000 - 0.0002i 0.0000 + 0.0002i 0.0000 + 0.0005i 0.0000 + 0.0007i 0.0000 + 0.0005i 0.0000 + 0.0002i 0.0000 + 0.0003i 0.0000 + 0.0007i 0.0000 + 0.0008i 0.0000 + 0.0007i 0.0000 + 0.0003i -0.0000 - 0.0003i -0.0000 - 0.0007i -0.0000 - 0.0008i -0.0000 - 0.0007i -0.0000 - 0.0003i -0.0000 - 0.0001i -0.0000 - 0.0002i -0.0000 - 0.0002i -0.0000 - 0.0002i -0.0000 - 0.0001i 0.0000 + 0.0001i 0.0000 + 0.0002i 0.0000 + 0.0002i 0.0000 + 0.0002i 0.0000 + 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0001i 0.0001 + 0.0001i 0.0000 + 0.0001i 0.0000 + 0.0000i -0.0000 - 0.0000i -0.0000 - 0.0001i -0.0001 - 0.0001i -0.0000 - 0.0001i -0.0000 - 0.0000i -0.0000 - 0.0000i -0.0001 - 0.0001i -0.0001 - 0.0001i -0.0001 - 0.0001i -0.0000 - 0.0000i 0.0000 + 0.0000i 0.0001 + 0.0001i 0.0001 + 0.0001i 0.0001 + 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0006i 0.0000 + 0.0004i 0.0000 + 0.0000i -0.0000 - 0.0004i -0.0000 - 0.0006i -0.0000 - 0.0006i -0.0000 - 0.0004i 0.0000 + 0.0000i 0.0000 + 0.0004i 0.0000 + 0.0006i -0.0000 - 0.0008i -0.0000 - 0.0005i 0.0000 + 0.0000i 0.0000 + 0.0005i 0.0000 + 0.0008i 0.0000 + 0.0008i 0.0000 + 0.0005i 0.0000 + 0.0000i -0.0000 - 0.0005i -0.0000 - 0.0008i 0.0000 + 0.0002i 0.0000 + 0.0001i 0.0000 + 0.0000i -0.0000 - 0.0001i -0.0000 - 0.0002i -0.0000 - 0.0002i -0.0000 - 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0001i 0.0000 + 0.0002i -0.0001 - 0.0001i -0.0000 - 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0001i 0.0001 + 0.0001i 0.0001 + 0.0001i 0.0000 + 0.0001i 0.0000 + 0.0000i -0.0000 - 0.0001i -0.0001 - 0.0001i 0.0001 + 0.0001i 0.0000 + 0.0000i 0.0000 + 0.0000i -0.0000 - 0.0000i -0.0001 - 0.0001i -0.0001 - 0.0001i -0.0000 - 0.0000i 0.0000 + 0.0000i 0.0000 + 0.0000i 0.0001 + 0.0001i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0180 - 0.0011i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0179 + 0.0038i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0178 + 0.0041i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0175 + 0.0052i -0.0173 + 0.0055i -0.0173 + 0.0055i -0.0173 + 0.0055i -0.0173 + 0.0055i -0.0173 + 0.0055i -0.0173 + 0.0055i -0.0173 + 0.0055i -0.0173 + 0.0055i -0.0173 + 0.0055i -0.0173 + 0.0055i
    figure; current(ant_ClosedEnded,70e6)

    图包含一个坐标轴对象。坐标轴对象with title Current distribution contains 3 objects of type patch.

    More About

    expand all

    References

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

    See Also

    |

    Topics

    Introduced in R2021a

    Antenna Toolbox Documentation

    金宝app

    混合Beamforming for Massive MIMO Phased Array Systems

    混合Beamforming for Massive MIMO Phased Array Systems

    Download the white paper