Example19 Balanced Line(Coupled Line) without Connector

General

 

  • The differential-mode and common-mode S-parameters are solved for a balanced line with connectors.
     

  • How to Reduce the Calculation Time

 

Analysis Space

Item

Settings

Analysis Space

3D

Model unit

mm

 

Analysis Conditions

Item

Settings

Solvers

Electromagnetic Analysis [Hertz]

Analysis Type

Harmonic analysis

Options

Select “Ignore the influence of face/edge electrode thickness” *

 

* This is the default setting. There are no face electrodes with this model. Therefore it is irrelevant to select it or not.

xx

 

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

Tab

Setting Item

Settings

Mesh Tab

Element type

2nd-order element

Multigrid/Adaptive Mesh Method

Select “Use the adaptive mesh method”.

Frequency-Dependent Meshing

Reference frequency: 1×10^9[Hz]

Select “The conductor bodies thicker than the skin depth constitute the boundary condition.”

Harmonic analysis

Frequency

Minimum: 1×10^8[Hz]

Maximum: 1.5×10^9[Hz]

Sweep Type

Select Linear step

Division number: 10

Sweep Setting

Select Discrete sweep

Input

1.0[W]

Open boundary

Type

Absorbing boundary

Order of Absorbing Boundary

1st degree

Model

Two microstriplines 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

I/O Port

50[Ω]

AUTO_PORT_2/Face

Electric

I/O Port

50[Ω]

AUTO_PORT_3/Face

Electric

I/O Port

50[Ω]

AUTO_PORT_4/Face

Electric

I/O Port

50[Ω]

Outer Boundary Condition

Electric

Electric wall

 

Results

On the [Results] tab

 

 

click [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. Then

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.

 

Table 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”, and press the [XY Graph]button.
The frequency plots 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.