Modeling a Powerbus with IE3D
Geometry and setup 
Doublesided PCB:
 Size: 125 mm × 100 mm × 1 mm
 Top and bottom metal: PEC
 Dielectric: FR4, ε_{r} = 4.5,
dielectric loss tangent = 0.015
Simulation Setup:
 Meshing parameters: meshing frequency = 2 GHz, cells/wavelength = 15
 Mesh alignment is enabled: Align polygons and dielectrics
 Adaptive IntelliFit (AIF): disabled
 Matrix solver: default SVSa
 Frequency Parameters: 5 MHz  2 GHz, Step Size = 5 MHz
 Excitation: Voltage source (1 V, 50 ohms)
ie3d_powerbus.zip

Simulation result 
Simulation Time: 5111 seconds Number of Cells/Volumes/Unknowns: 300/143/1136 
Decisions the user must make that affect the
accuracy of the result 
 Define the dielectric block as a finite substrate: By default, the substrate size is infinitely large in IE3D.
In this case, the dielectric block should be defined as a finite substrate. Please refer to the comments for
details.
 Align meshing between the polygons and the finite dielectric: The meshing alignment between
the finite dielectrics and the patch is extremely critical to the simulation results.
 Define a port as a pair of positive and negative terminals: When there is no infinite ground plane, a user
needs to define a port as a pair of positive and negative terminals. Numerical error may be introduced if we
don't define a port in pair (+, ) or define a differential port (vertical localized or horizontal localized
port with selfcontained + and  terminals) on a structure without an infinite ground plane.

Comments 
 
Screen shots
Fig. 1. Simulation model
Fig. 2. Simulation meshes
Fig. 3. Input impedance
Fig. 4. Electric field at 3 m,
θ=0^{°}, φ=0^{°}
Fig. 5. Electric field at 3 m,
θ=90^{°}, φ=0^{°}
Fig. 6. Electric field at 3 m,
θ=90^{°},
φ=90^{°}  