Home / Examples / Electromagnetic Analysis [Hertz] / Example 8: Open Stub

Example 8: Open Stub

General

An open stub formed on a dielectric substrate is characterized.
Unless specified in the list below, the default conditions will be applied.

[How to Reduce the Calculation Time]

Analysis Space

Item	Settings
Analysis Space	3D
Model Unit	mm

Analysis Conditions

Item	Settings
Solver	Electromagnetic Analysis [Hertz]
Analysis Type	Harmonic Analysis

The harmonic analysis is set as follows.

Tab	Setting Item	Settings
Mesh Tab	Element type	2nd-order Element
	Multigrid/Adaptive Mesh Method	Select [Apply adaptive meshing].
	Frequency-Dependent Meshing	Reference frequency: 5x109 [Hz] Select [The conductor bodies thicker than the skin depth constitute the boundary condition].
Harmonic analysis	Sweep Type	Select [Linear Step by Division Number]
	Sweep Setting	Minimum: 1×109 [Hz] Maximum: 10x109 [Hz] Division Number: 100
	Sweep Setting	Select Fast sweep S-parameter Tolerance: 1x10-3
	Input	1.0 [W]

Model

An open stub is formed on a substrate (SUB) with microstrip lines. A box for the ambient air is created on the substrate.

This model has two ports: PORT1 and PORT2. An integration path is set up on each port.

Body Attributes and Materials

You may give the thickness to the electrodes (EC bodies) in the body attribute. That does not affect the simulation.
(Related information: Analysis Condition, Electromagnetic Analysis tab, and "Take thickness of face/edge electrode into account")

Body Number/Type	Body Attribute Name	Material Name
0/Solid	SUB	006_Glass_epoxy *
1/Sheet	EC	003_Ag
2/Sheet	EC	003_Ag
3/Solid	AIR	001_Air(*)

* Available from the material DB

Boundary Conditions

Boundary Condition Name/Topology	Tab	Boundary Condition Type	Settings
PORT1/Face	Electric	Port	Reference Impedance: Select [Specify] and enter 50 ohms. Number of Modes Number of Precalculated Modes: 5 Number of Modes Used in the Actual 3D Analysis: 1 Select Modes: None
PORT2/Face	Electric	Port	Same as Above.
Outer Boundary Condition	Electric	Electric Wall

Results

The reflection and the transmission characteristics of the open stub are shown below.