design

Design a custom transmission line in stripline form around a specified frequency

Since R2024b

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Syntax

mline = design(custlineobj,frequency)
mline = design(___,Name=Value)

Description

mline = design(custlineobj,frequency) designs a custom stripline around a specified frequency with default values.

mline = design(___,Name=Value) designs a custom stripline transmission line around a specified frequency with additional options specified using name-value arguments.

Note

RF components designed using the design function operate around the specified frequency with a 10%-15% tolerance.

example

Examples

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Open Live Script

This example shows the design, and the reflection coefficient plot of all ports, of a custom stripline at 2.5 GHz with even mode impedance of 50 ohms and odd mode impedance of 36 ohms

Design the stripline

Use the design function on the custom stripline object

mline = design(stripLineCustom(TraceType='Differential'),2.4e9,Z0e=70,Z0o=36)
mline = 
  stripLineCustom with properties:

               TraceType: 'Differential'
             TraceLength: 0.0216
              TraceWidth: 0.0042
            TraceSpacing: 2.5046e-04
            TraceOffsetX: 0
                  Height: 0.0030
       GroundPlaneLength: 0.0842
     LeftCoupledTraceGap: 0.0082
    RightCoupledTraceGap: 0.0082
               Substrate: [1×1 dielectric]
               Conductor: [1×1 metal]

Vizualize the stripline

Use the show and layout functions to visualize the stripline

show(mline)

Figure contains an axes object. The axes object with title stripLineCustom element, xlabel x (mm), ylabel y (mm) contains 18 objects of type patch, surface. These objects represent PEC, feed, Teflon.

layout(mline)

Figure contains an axes object. The axes object with title stripLineCustom Layout, xlabel x (m), ylabel y (m) contains 11 objects of type line, text. One or more of the lines displays its values using only markers These objects represent Board Shape, Layer1, Layer3, Layer5, Feed.

Calculate the s-parameters

Calculate the s-parameters of the stripline from 1.5 GHz to 2.5 Ghz with 41 data points and 75 ohm reference impedance

freq=linspace(1.5e9,3.5e9,41);
spline=sparameters(mline,freq,50);

Plot the reflection coefficient

Plot the reflection coefficient of all ports

figure;
rfplot(spline,'diag','abs')
title('Differential stripline reflection coefficient 75 ohm reference impedance')

Figure contains an axes object. The axes object with title Differential stripline reflection coefficient 75 ohm reference impedance, xlabel Frequency (GHz), ylabel Magnitude contains 6 objects of type line. These objects represent abs(S_{11}), abs(S_{22}), abs(S_{33}), abs(S_{44}), abs(S_{55}), abs(S_{66}).

Input Arguments

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Custom stripline transmission line, specified as a custom stripline object

Example: mline = stripLineCustom; design(mline,2e9) designs a microstrip transmission line around a frequency of 2 GHz.

Data Types: char | string

Design frequency of the transmission line, specified as a real positive scalar in hertz.

Example: 5.9e9

Data Types: double

Name-Value Arguments

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Example: Z0e=45

Specify optional name-value pairs of arguments as Name=Value, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other input arguments, but the order of the pairs does not matter

Number of left traces coupled with reference trace

Example: NumLeftTrace=2

Number of right traces coupled with reference trace

Example: NumRightTrace=2

Characteristic impedance specified in ohms when TraceType is single.

Example: Z0=75

Even mode impedance specified in ohms when TraceType is differential.

Example: Z0e=45

Odd mode impedance specified in ohms when TraceType is differential.

Example: Z0o=72

Note

If TraceType is Single the reference impedance used is Z0. If TraceType is Differential the reference impedances used are the even and odd mode impedances Z0e

and Z0o. If the impedances are not specified then the default values will be used in the design.

Output Arguments

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A custom stripline designed around a specified frequency

Version History

Introduced in R2024b