Example7 Dipole Antenna


  • The perfectly matched layer (PML) is used to analyze a dipole antenna.

  • Unless specified in the list below, the default conditions will be applied.

  • [How to Reduce the Calculation Time]

  • The animation for the radiation characteristics is created at the end of this session.


Analysis Space



Analysis Space


Model unit



Analysis Conditions




Electromagnetic Analysis [Hertz]

Analysis Type

Harmonic analysis


Select “Ignore the influence of face/edge electrode thickness” *

* This is the default setting. There are no face electrodes with this model. Therefore it is irrelevant to select it or not.


Mesh tab, Harmonic analysis tab and Open boundary tab are set as follows.


Setting Item


Mesh Tab

Element type

1st-order element

Multigrid/Adaptive Mesh Method

Select “Use the adaptive mesh method”.

Frequency-Dependent Meshing

Reference frequency: 5×10^9[Hz]

Select “The conductor bodies thicker than the skin depth constitute the boundary condition.”


ANTENNA is thicker than the skin depth.

Its surface will be set with the proper boundary condition based on the material automatically.

Harmonic analysis


Minimum: 3×10^9[Hz]

Maximum: 6×10^9[Hz]

Sweep Type

Select “Linear step”

Division number: 100

Sweep Setting

Select Fast sweep

S-parameters variation: 1×10^-3



Open boundary


PML (Perfectly Matched Layers)

Thickness of PML Layer

0.2 wavelength *

* It is 0.3 by default. To shorten the calculation time, it is changed to 0.2.


Two conductor rods are placed in the air box. The rods are rectangle solid bodies.

Set the I/O port boundary condition on a sheet body connecting the conductor rods.



Body Attributes and Materials

Body Number/Type

Body Attribute Name

Material Name



104_Stainless_steel *



104_Stainless_steel *


Imprinting body





* Available from the Material DB



Boundary Conditions

Boundary Condition Name/Topology


Boundary Condition Type




I/O Port

Reference Impedance: Select “Specify”

and enter 50[Ohm].

Number of Modes

Number of precalculated modes: 5

Number of modes used in the actual analysis: 1

Select modes: none



Open boundary

Select PML on the open boundary tab of the analysis condition setting.

Outer Boundary Condition


Electric wall





The resonant frequency is around 4.5[GHz}.




The perfectly matched layers with body attributes of RESERVED_PML_xx are generated automatically.

The green PML characters below will not be displayed on the results window. Just reference only.



How to View the Radiation Patterns

The polar coordinate system is suitable to view the radiation patterns. The observation point is specified by φ and θ.

The observation section is specified by the range of φ and θ.

Enter the parameters in the directivity calculation dialog box as follows.


At Frequency, select 5[GHz].

At Observation Point, φ: Min 0[deg], Max 90[deg], Division number 1. Note that φ=0[deg] represents XZ plane. φ=90[deg] represents YZ plane.

θ: Min 180[deg], Max -180[deg], Division number 180.

At Display, select rE(θ).


The resulting radiation pattern at the specified section is shown below.

The table indicates how to set the typical observation sections.


  • See also [Electromagnetic Waves Directivity].



The “Directivity Calculation” dialog box Radiation pattern




Observation Point (φ, θ)


[Setting] – [Horizontal axis]

XZ plane, YZ plane


φ(0, 90, 1), θ(-180, 180, 100)



XZ plane, YZ plane


φ(0, 90, 1), θ(-180, 180, 100)



XY plane


φ(-180, 180, 100), θ(90, 90, 0)



XY plane


φ(-180, 180, 100), θ(90, 90, 0)




Comparison with the Theoretical Results

The theoretical results and radiation pattern of the half wavelength dipole antenna are compared. The calculation condition is as follows.

– Frequency 5.01GHz (select the frequency so as to make the length of antenna 1/2 wavelength)

– Radiation pattern measured at the XZ plane Setting of the observation point is; φ(minimum value: 0[deg], maximum value: 90[deg], number of divisions: 0), θ(minimum value: -180[deg], maximum value: 180[deg], number of divisions: 100).

– Display: POWER, unit: dBi

– “Gain type” and “Received power referenced” are selected on the “Electromagnetic Waves Directivity” tab Operation is as follows. If you press the “Other settings” of the Directivity Calculation dialog box, “Directivity Setting” dialog box will appear. Then, gain type and received power referenced are selected.


How to Create the Animation

Animations tend to look better when the larger ambient zone is set, e.g..more than one wavelength.
However, that might increase the number of meshes.
To suppress the number of meshes, try the absorbing boundary instead of PML.

The animation will look better with smaller meshes.

The left figure is the model. The right figure is the contour of the electric field sectioned by the plane encompassing the antenna.




# Setting Item

Analysis Condition Setting -> Open Boundary tab -> Absorbing boundary

Modeling -> Air sphere -> Radius: 60

Modeling -> Mesh size: 4

Analysis Condition Setting -> Mesh tab -> Meshing Setup -> 2nd-order element


# Results Window

  • [Analysis type]: Electromagnetic waves analysis

  • [Mode]: 4.5GHz

  • [Field type]: Electric field

  • [Component]: Size

  • [Phase]: 90° *

  • [Scale]: Log

* This setting is for the better look of contour. It does not affect the animation.


# Contour tab in Graphics Setup

  • Deselect “Automatic”

  • Minimum value: 100

  • Maximum Value: 1000


# Section

The contour of section that is in the center of the ambient air and parallel to the YZ plane is shown in the right diagram above.
The animation displays the electromagnetic waves radiation.


  • See [How to Create Animation[ for detail.


  • Make the mesh size bigger. See [Mesh tab] for details.

  • Select “1st-order element” See [Mesh tab] for details.

  • Disable adaptive mesh. See [Mesh tab] for details.