Example 2: Circulator

A three-port circulator consisting of a Y-shape waveguide and a ferrite cylinder is analyzed.
The device's S-parameters are solved.
Unless specified in the list below, the default conditions will be applied.

Item	Settings
Solver	Electromagnetic Analysis [Hertz]
Analysis Type	Harmonic Analysis
Options	Field Data to Save: Don't save

The harmonic analysis is set up as follows.

Tabs	Setting Item	Settings
Mesh Tab	Element Type	2nd-order Element
	Multigrid/Adaptive Mesh Method	Select [Apply adaptive meshing].
	Frequency-Dependent Meshing	Reference Frequency: 10x109 [Hz] Select [The conductor bodies thicker than the skin depth constitute the boundary condition]. No conductive bodies are used in this example. However the setting above is required.
Harmonic analysis	Sweep Type	Select Linear Step by Division Number.
	Sweep Setting	Minimum: 0.8x1010 [Hz] Maximum: 1.2x1010 [Hz] Division: 20
	Sweep Setting	Select Discrete Sweep
	Input	1.0 [W]

The Y-shape waveguide is created by copying a solid body and uniting them with boolean operation.

The port boundary condition is set on their I/O faces.

The walls of the waveguide are defined as electric wall in the external boundary condition.

The mesh size of the ferrite cylinder is set to 1.

* Available from the material DB

The static magnetic field applied on the ferrite (Ferrite) is set up in the body attribute.

Body Attribute Name	Tab	Material Name
Ferrite	Magnetostatic Field	1.00X104 [A/m]

The material properties of Ferrite are set up as follows:

Material Name	Tab	Properties
Ferrite	Permittivity	Relative Permittivity: 1.1x101
	Permeability	Select [Tensor Permeability].
	Magnet	Magnetization Strength: 1.3×10-1 Properties of Ferrite: ΔH: 7.958×103 [A/m] g Coefficient: 2.0×100

Note) The following values are used for the magnet. Saturation magnetic flux density: 1300 [Gauss], Magnetic resonance FWHM: 100 [Oe],

Relative permittivity: 11, tanD: 0.0015. 1300[Gauss] = 0.13 [T], 100 [Oe] = 7958 [A/m]

Boundary Condition Name/Topology	Tab	Boundary Condition Type	Settings
PORT1/Face	Electric	Port	Reference Impedance: Select [Use the characteristic impedance calculated from the port structure] 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 PORT1
PORT3/Face	Electric	Port	Same as PORT1
Outer Boundary Condition	Electric	Electric Wall

The outer boundary of Air:

The outer boundary of Air is set as the electric wall, which is the perfect conductor.

Shown below is the I/O characteristics (S-parameters) between PORT1 and PORT2.

The isolation is exhibited around 10 GHz.