txlineWRLGC

Create lossy RLGC transmission line

Since R2026a

expand all in page

    Description

    Use the txlineWRLGC object to create a lossy RLGC transmission line for enabling network characterization for signal-integrity workflows, such as time-domain reflectometry.

    Creation

    Syntax

    Wrlcgtxline = txlineWRLGC
    Wrlcgtxline = txlineWRLGC(Name=Value)

    Description

    Wrlcgtxline = txlineWRLGC creates a default lossy RLGC transmission line object.

    Wrlcgtxline = txlineWRLGC(Name=Value) sets properties using one or more name-value arguments. For example, Wrlcgtxline = txlineWRLGC(Linelength=0.1) creates an lossy RLGC transmission line of length 0.1 meters. Properties you do not specify retain their default values.

    example

    Properties

    expand all

    Name of the lossy RLGC transmission line, specified as a string scalar or a character vector.

    Example: Name='Wrlcgline1'

    Data Types: char | string

    Number of signal conductors in the lossy RLGC transmission line, specified as a nonnegative integer.

    Example: Nline=2

    Data Types: double

    Resistor values, specified as a nonnegative scalar in Ω/m or as a matrix of size Nline-by-Nline with nonnegative elements in Ω/m. The object uses resistor values in the upper triangular part of the resistance-per-length matrix, that are evaluated at low frequencies.

    Note

    Ro and Lo matrices must remain nonnegative.

    Example: Ro=0.5

    Data Types: double

    Square root of frequency coefficients in the upper triangular portion of the resistance-per-length matrix, specified as a nonnegative scalar in Ω/m or a nonnegative 1-D vector with each element unit in Ω/m.

    Example: Ro=0.5

    Data Types: double

    Inductance values in the upper triangular portion of the inductance-per-length matrix, evaluated at high frequencies, specified as a nonnegative scalar in H/m or a nonnegative 1-D vector with each element unit in H/m.

    Note

    Ro and Lo matrices must remain nonnegative.

    Example: Lo=0.5

    Data Types: double

    Capacitance values in the upper triangular portion of the capacitance-per-length matrix, evaluated at high frequencies, specified as a nonnegative scalar in F/m or a 1-D nonnegative vector with each element unit in F/m.

    Note

    Go and Co matrices have positive diagonals and nonnegative off-diagonals.

    Example: Co=0.5

    Data Types: double

    Conductance values in the upper triangular portion of the conductance-per-length matrix, evaluated at low frequencies, specified as a nonnegative scalar in S/m or a nonnegative 1-D vector with each element unit in S/m.

    Note

    Go and Co matrices must be positive above the diagonal and non-positive below the diagonal.

    Example: Go=0.5

    Data Types: double

    Frequency coefficients of the conductance in the upper triangular portion of the resistance-per-length matrix, specified as a nonnegative scalar in S/m or a nonnegative 1-D vector with each element unit in S/m.

    Example: Go=0.5

    Data Types: double

    Frequency at which the Gd matrix corresponds to the dielectric loss tangent, specified as a nonnegative scalar in Hz.

    Example: DielectricFrequency=2e9

    Data Types: double

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

    Example: LineLength=0.0200

    Data Types: double

    This property is read-only.

    Number of input and output ports, represented as positive scalar.

    Data Types: double

    This property is read-only.

    Terminals of the lossy RLGC transmission line, represented as a cell array of strings.

    Data Types: char | string

    Object Functions

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

    Examples

    collapse all

    Open Live Script

    Define the resistance, inductance, capacitance, and conductance values of a lossy RLGC transmission line.

    Ro = 5.31637E+01;
Lo = 2.66100E-07;
Co = 1.44200E-10;
Go = 0;

    Define the square root of frequency coefficients of resistance and conductance values.

    Rs = 5.20195E-03;
Gd = 1.34700E-11;

    Define the scaling vectors to ensure that elements of the Ro and Lo matrices remain nonnegative, while elements of the Go and Co matrices are positive above the diagonal and non-positive below the diagonal.

    tempPos = [1 0.1 1].';
tempNeg = [1 -0.1 1].';

    Define the line length of the lossy RLGC transmission line.

    lineLength = 1e-2;

    Create a txlineWRLGC object with its defined parameters.

    w = txlineWRLGC('Nline', 2, 'Lo', Lo*tempPos, 'Co', Co*tempNeg, ...
    'Ro', Ro*tempPos, 'Rs', Rs*tempPos, ...
    'Go', Go*tempNeg, 'Gd', Gd*tempNeg, 'LineLength', lineLength);

    Calculate the S-parameters of the lossy RLGC transmission line.

    freq = 1e6:10e6:40e9;
sobj = sparameters(w,freq)
    sobj = 
  sparameters with properties:

      Impedance: 50
       NumPorts: 4
     Parameters: [4×4×4000 double]
    Frequencies: [4000×1 double]

    Version History

    Introduced in R2026a

    See Also

    |