Modeling a CenterDriven Dipole with CST
Geometry and setup 
Geometry: L= 1 m,
a = 0.5 mm Model parameters:
 Frequency: 50 MHz ~ 400 MHz
 Steady state accuracy limit: 60 dB
Mesh
definition:
 Mesh type: Hexahedral
 Mesh density control: Lines per wavelength = 30,
Others = Default
 Special mesh properties:
Refine at PEC/lossy metal edges by factor = 6,
Others = Default
 Automesh
Excitation: Discrete port
(1 W, 50 ohms)
cst_dipole.zip

Simulation result 
Simulation time: 12 secs
Number of mesh cells: 3600
Excitation duration: 2.031171e+001 ns
Calculation time for excitation: 4 secs
Number of calculated pulse widths: 3.49899
Simulated number of time steps: 8988
Maximum number of time steps: 51374 
Decisions the user must make that affect the
accuracy of the result 
 Mesh density control: the minimum Lines per wavelength is 30.
 Special mesh properties: 6 or greater value is needed for 'Refine at PEC/lossy metal edges by factor'
to obtain higher accuracy.

Comments 
 Adding the source requires a gap between the two wires. What
is the source gap length?
In this model, the interval
between two antenna parts is 1 mm.
 What if we model the dipole as a flat ribbon?
Substituting a 2mm
flat ribbon for a 0.5mm radius round wire is not allowed in this model.
 
Screen shots
Fig. 1. Simulation model
Fig. 2. Simulation meshes
Fig. 3. Input impedance
Fig. 4. Input impedance at the first
resonant
frequency  