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Model RLCG transmission line

The RLCG Transmission Line block models the RLCG transmission line described in the block dialog box in terms of its frequency-dependent resistance, inductance, capacitance, and conductance. The transmission line, which can be lossy or lossless, is treated as a two-port linear network.

where *z*′ = *z* + Δ*z*.

The block lets you model the transmission line as a stub or as a stubless line.

If you model an RLCG transmission line as a stubless line, the
RLCG Transmission Line block first calculates the ABCD-parameters
at each frequency contained in the modeling frequencies vector. It
then uses the `abcd2s` function to
convert the ABCD-parameters to S-parameters.

The block calculates the ABCD-parameters using the physical
length of the transmission line, *d*, and the complex
propagation constant, *k*, using the following equations:

*Z*_{0} and *k* are
vectors whose elements correspond to the elements of *f*,
a vector of modeling frequencies. Both can be expressed in terms of
the resistance (*R*), inductance (*L*),
conductance (*G*), and capacitance (*C*)
per unit length (meters) as follows:

If you model the transmission line as a shunt or series stub,
the RLCG Transmission Line block first calculates the ABCD-parameters
at each frequency contained in the vector of modeling frequencies.
It then uses the `abcd2s` function
to convert the ABCD-parameters to S-parameters.

When you set the **Stub mode** parameter in
the mask dialog box to `Shunt`, the two-port network
consists of a stub transmission line that you can terminate with either
a short circuit or an open circuit as shown here.

*Z _{in}* is the input impedance
of the shunt circuit. The ABCD-parameters for the shunt stub are calculated
as

When you set the **Stub mode** parameter in
the mask dialog box to `Series`, the two-port network
consists of a series transmission line that you can terminate with
either a short circuit or an open circuit as shown here.

*Z _{in}* is the input
impedance of the series circuit. The ABCD-parameters for the series
stub are calculated as

**Resistance per length (ohms/m)**Vector of resistance values in ohms per meter.

**Inductance per length (H/m)**Vector of inductance values in henries per meter.

**Capacitance per length (F/m)**Vector of capacitance values in farads per meter.

**Conductance per length (S/m)**Vector of conductance values in siemens per meter.

**Frequency (Hz)**Vector of frequency values at which the resistance, inductance, capacitance, and conductance values are known.

**Interpolation method**Specify the interpolation method the block uses to calculate the parameter values at the modeling frequencies. Your choices are

`Linear`,`Spline`, or`Cubic`.**Transmission line length (m)**Physical length of the transmission line.

**Stub mode**Type of stub. Your choices are

`Not a stub`,`Shunt`, or`Series`.**Termination of stub**Stub termination for stub modes

`Shunt`and`Series`. Choices are`Open`or`Short`. This parameter becomes visible only when**Stub mode**is set to`Shunt`or`Series`.

For information about plotting, see Create Plots.

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