monocone

Create monocone antenna on circular ground plane

Since R2020a

Description

The monocone object creates a monocone antenna on a circular ground plane. A classical monocone antenna consists of a cone and a ground plane. To increase the bandwidth of the antenna, you can modify the antenna by merging the cone with a circular cylinder. By default, the monocone object creates the modified version.

Create a classical monocone antenna (without the cylinder on top) using one of these methods:

• Set the height of the antenna to equal the sum of the cone height and the feed height.

• Set the cone height to equal half of the difference between the total height and the feed height. Then set the radius at the aperture to twice the radius at the junction.

Creation

Syntax

ant = monocone

ant = monocone(Name,Value)

Description

ant = monocone creates a monocone antenna with the feedpoint at the center of the ground plane. The default dimensions are for a resonant frequency of 3.8 GHz.

ant = monocone(Name,Value) sets properties using one or more name-value pairs. For example, ant = monocone('Height',0.0560) creates a monocone antenna with a total height of 0.0560 meters.

Properties

Radii — Antenna radii

[5.0000e-04 0.0110 0.0110] (default) | three-element real vector

Antenna radii, specified as a three-element real vector with each element unit in meters.

• The first element represents the narrow radius of the cone.

• The second element represents the radius at the junction of the cone and the cylinder.

• The third element represents the radius at the top of the cylinder.

Example: 'Radii',[6.3300e-04 0.0546 0.0220]

Example: ant.Radii = [6.3300e-04 0.0546 0.0220]

Data Types: double

Height — Total height of antenna

0.0250 (default) | positive scalar

Total height of the antenna from the ground plane to the aperture of the antenna, specified as a positive scalar in meters.

Example: 'Height',0.0560

Example: ant.Height = 0.0560

Data Types: double

ConeHeight — Vertical height of cone

0.0115 (default) | positive scalar

Vertical height of the cone from the apex of the cone to the junction of the cone and the cylinder, specified as a positive scalar in meters.

Example: 'ConeHeight',0.02250

Example: ant.ConeHeight = 0.02250

Data Types: double

FeedHeight — Gap between cone and ground plane

5.0000e-04 (default) | positive scalar

Gap between the cone and the ground plane, specified as a positive scalar in meters.

Example: 'FeedHeight',0.0034

Example: ant.FeedHeight = 0.0034

Data Types: double

FeedWidth — Width of feed

5.0000e-04 (default) | positive scalar

Width of the feed, specified as a positive scalar in meters.

Example: 'FeedWidth',0.0050

Example: ant.FeedWidth = 0.0050

Data Types: double

GroundPlaneRadius — Radius of ground plane

0.0325 (default) | positive scalar

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

Example: 'GroundPlaneRadius',0.0050

Example: ant.GroundPlaneRadius = 0.050

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

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

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. For more information, see lumpedElement.

Example: 'Load',lumpedElement, where lumpedElement is load added to the antenna feed.

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

Tilt — Tilt angle of antenna

0 (default) | scalar | vector

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: Tilt=[90 90],TiltAxis=[0 1 0;0 1 1] tilts the antenna at 90 degrees about the two axes defined by the vectors.

Note

The wireStack antenna object only accepts the dot method to change its properties.

Data Types: double

TiltAxis — Tilt axis of antenna

[1 0 0] (default) | three-element vector of Cartesian coordinates | two three-element vectors of Cartesian coordinates | 'X' | 'Y' | 'Z'

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: TiltAxis = 'Z'

Data Types: double

Object Functions

coneangle2size	Calculates equivalent cone height, broad radius, and narrow radius for cone
show	Display antenna, array structures or shapes
axialRatio	Axial ratio of antenna
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
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, 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
vswr	Voltage standing wave ratio of antenna

Examples

Default Monocone Antenna

Create and view a default monocone antenna.

ant = monocone

ant = 
  monocone with properties:

                Radii: [5.0000e-04 0.0110 0.0110]
    GroundPlaneRadius: 0.0325
           ConeHeight: 0.0115
               Height: 0.0250
           FeedHeight: 5.0000e-04
            FeedWidth: 5.0000e-04
            Conductor: [1x1 metal]
                 Tilt: 0
             TiltAxis: [1 0 0]
                 Load: [1x1 lumpedElement]

show(ant)

Monocone Antenna with Infinite Ground Plane

Create a monocone antenna with an infinite ground plane.

ant = monocone;
ant.GroundPlaneRadius = inf;
show(ant)

Plot the radiation pattern of the monocone antenna for the given frequency.

pattern(ant,3.94e9)

Monocone Antenna Without A Cylinder

Create a classical monocone antenna by setting the total height of the antenna to equal the sum of cone height and feed height.

ant = monocone;
ant.Height = ant.ConeHeight+ant.FeedHeight;
show(ant)

Calculate antenna impedance over the given frequency span.

impedance(ant,(1e9:0.1e9:6e9)) 

References

[1] McDonald, James L., and Dejan S. Filipovic. “On the Bandwidth of Monocone Antennas.” IEEE Transactions on Antennas and Propagation 56, no. 4 (April 2008): 1196–1201. https://doi.org/10.1109/TAP.2008.919226.

Version History

Introduced in R2020a