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Home / Examples / Electromagnetic Analysis [Hertz] / Example 19: Differential Lines with Connector

Example 19: Differential Lines with Connector

General

 

 

Analysis Space

Item

Settings

Analysis Space

3D

Model Unit

mm

 

Analysis Conditions

Item

Settings

Solver

Electromagnetic Analysis [Hertz]

Analysis Type

Harmonic Analysis

 

 

 

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

Tab

Setting Item

Settings

Mesh Tab

Element Type

2nd-order Element

Adaptive Meshing

Select [Apply adaptive meshing].

Frequency-Dependent Meshing

Reference Frequency: 1x109 [Hz]

Select [The conductor bodies thicker than the skin depth constitute the boundary condition].

Harmonic Analysis

Sweep Type

Select [Linear Step by Number of Divisions]

Sweep Setting

Minimum: 1x108 [Hz]

Maximum: 1.5x109 [Hz]

Division: 10

Sweep Setting

Select Discrete Sweep

Input

1.0 [W]

Open boundary

Type

Absorbing boundary

Order of Absorbing Boundary

1st-order

Model

Two microstrip lines are placed in parallel. They are connected to co-axial connectors.

The connectors are octagonal cylinders. Their end faces are set with the [I/O port] boundary condition.

The integral path is bridging the inner conductor and the outer perimeter.

Electric wall surrounds the model.

 

 

Body Attributes and Materials

Body Number/Type

Body Attribute Name

Material Name

1/Solid

CONNECTOR

Resin

4/Solid

CONNECTOR

Resin

5/Solid

CONNECTOR

Resin

7/Solid

CONNECTOR

Resin

15/Solid

AIR

000_Air(*)

22/Solid

METAL

003_Ag *

23/Solid

METAL

003_Ag *

25/Solid

METAL

003_Ag *

26/Solid

METAL

003_Ag *

27/Solid

METAL

003_Ag *

28/Solid

METAL

003_Ag *

29/Solid

SUBSTRATE

006_Glass_epoxy *

* Available from the material DB

 

Resin's property is as follows.

Material Name

Permittivity

Resin

2.3

Boundary Conditions

Boundary Condition Name/Topology

Tab

Boundary Condition Type

Settings

AUTO_PORT_1/Face

Electric

Port

50 [Ω]

AUTO_PORT_2/Face

Electric

Port

50[Ω]

AUTO_PORT_3/Face

Electric

Port

50[Ω]

AUTO_PORT_4/Face

Electric

Port

50 [Ω]

Outer Boundary Condition

Electric

Electric Wall

 

Results

On the [Results] tab

 

 

click [Show Characteristics Chart] and select SYZ Matrix.

 

On the SYZ matrix dialog box menu, click [Edit] and [Port Order Exchange/Balance Conversion].

Select PORT1 and PORT2, and click the [Pair up] button.

Select PORT3 and PORT4, and click the [Pair up] button.

You will see PORT(1,2)DIF, PORT(1,2)COM, PORT(3,4)DIF, PORT(3,4)COM in this order. You may change the listing order. For example,

select PORT(1,2)COM and PORT(3,4)DIF and press the [Exchange] button.

 

The S matrix will be listed as in the table below.

 

Tabel 1. S Matrix Listing Order and Abbreviation

 

Port Number

Before Conversion

After Conversion

Title in Edit Dialog

Title in Edit Dialog

Note

Abbreviatied Title

1

AUTO_PORT_001:m1

DIFF(AUTO_PORT_001:m1,AUTO_PORT_002:m1)

Differential mode of AUTO_PORT_001 and AUTO_PORT_002

1d

2

AUTO_PORT_002:m1

DIFF(AUTO_PORT_003:m1,AUTO_PORT_004:m1)

Differential mode of AUTO_PORT_003 and AUTO_PORT_004

2d

3

AUTO_PORT_003:m1

COM(AUTO_PORT_001:m1,AUTO_PORT_002:m1)

Common (same phase) mode of AUTO_PORT_001 and AUTO_PORT_002

1c

4

AUTO_PORT_004:m1

COM(AUTO_PORT_003:m1,AUTO_PORT_004:m1)

Common (same phase) mode of AUTO_PORT_003 and AUTO_PORT_004

2c

 

 

In the SYZ Matrix dialog box, select [1 1], [1 2], [1 3] and [1 4] in the matrix element,
and click the [XY Graph]button. The frequency plots below of S parameters will appear.

 

 

See the table below for the S(x,x) notation.

 

 

Table 2. S Matrix Lookup Table

Title in Graph

With Abbreviated Title

S(1,1)

S(1d,1d)

S(1,2)

S(1d,2d)

S(1,3)

S(1d,1c)

S(1,4)

S(1d,2c)

1d,2d,1c and 2c are the abbreviated titles.