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txlineEquationBased

Create equation-based transmission line

Since R2021a. Recommended over rfckt.txline.

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    Description

    Use the txlineEquationBased object to create an equation-based transmission line. You can set the loss, the phase velocity, and the interpolation type in this object. You can also use the txlineEquationBased object to model an equation-based transmission line in an RF systems using an rfbudget object or the RF Budget Analyzer app.

    Equation-based transmission line

    Creation

    Syntax

    eqtxline = txlineEquationBased
    eqtxline = txlineEquationBased(Name,Value)

    Description

    eqtxline = txlineEquationBased creates a default equation-based transmission line object.

    eqtxline = txlineEquationBased(Name,Value) sets Properties of the equation-based transmission line using one or more name-value arguments. For example, eqtxline = txlineEquationBased('Z0',75) creates an equation-based transmission line with the impedance of 75 ohms.

    example

    Properties

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    Name of the equation-based transmission line, specified as a string scalar or character vector.

    Example: 'Name','EQbased'

    Example: eqtxline.Name = 'EQbased'

    Operating frequency of the equation-based transmission line, specified as a positive scalar in Hz.

    Example: 'Frequency',2e9

    Example: eqtxline.Frequency = 2e9

    Characteristic impedance of the equation-based transmission line, specified as a positive scalar in ohms.

    Example: 'Z0',75

    Example: eqtxline.Z0 = 75

    Loss of the equation-based transmission line, specified as a scalar in dB.

    Example: 'LossDB',25

    Example: eqtxline.LossDB = 25

    Phase velocity of the equation-based transmission line, specified as a positive scalar in m/sec.

    Example: 'PhaseVelocity',2e9

    Example: eqtxline.PhaseVelocity = 2e9

    Type of interpolation set in the equation-based transmission line, specified as 'Linear', 'Spline', or 'Cubic'.

    Example: 'IntType','Spline'

    Example: eqtxline.IntType = 'Spline'

    Physical length of the equation-based transmission line, specified as a positive scalar in meters.

    Example: 'LineLength',0.020

    Example: eqtxline.LineLength = 0.020

    Stub transmission line termination in the equation-based transmission line, specified as 'NotApplicable', 'Open', or 'Short'.

    Example: 'Termination','Short'

    Example: eqtxline.Termination = 'Short'

    Type of stub in the equation-based transmission line, specified as 'NotAStub', 'Series', or 'Shunt'.

    Example: 'StubMode','Series'

    Example: eqtxline.StubMode = 'Series'

    This property is read-only.

    Number of input and output ports in equation-based transmission line, returned as positive scalar.

    This property is read-only.

    Terminals of the equation-based transmission line, returned as a cell array of strings.

    Object Functions

    sparametersCalculate S-parameters for RF data, network, circuit, and matching network objects
    groupdelayGroup delay of S-parameter object or RF filter object or RF Toolbox circuit object
    noisefigureCalculate noise figure of transmission lines, series RLC, and shunt RLC circuits

    Examples

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    Open Live Script

    Create an equation-based transmission line 50 cm in length. 

    eqtxline = txlineEquationBased('LineLength',0.05);

    Calculate the S-parameters of the equation-based transmission line over the frequency range 1–4 GHz.

    freq = linspace(1e9,4e9,51);
sparam = sparameters(eqtxline, freq)
    sparam = 
  sparameters with properties:

      Impedance: 50
       NumPorts: 2
     Parameters: [2x2x51 double]
    Frequencies: [51x1 double]

    Calculate the group delay of the equation-based transmission line at 2.4 GHz.

     gd = groupdelay(eqtxline,2.4e9)
    gd = 
1.6678e-10

    Version History

    Introduced in R2021a

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    See Also

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