Computed S-parameters, noise figure, OIP3, and group delay values
Handle to an
that contains the S-parameters, noise figure, OIP3, and group delay
values computed over the specified frequency range using the
analyze method. This property is empty by
analyze method treats
the transmission line, which can be lossy or lossless, as a 2-port
linear network. It computes the
of a stub or as a stubless line using the data stored in the
rfckt.twowire object properties as follows:
If you model the
transmission line as a stubless line, the
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.
analyze method calculates
the ABCD-parameters using the physical length of the transmission
line, d, and the complex propagation constant, k,
using the following equations:
Z0 and k are
vectors whose elements correspond to the elements of f,
the vector of frequencies specified in the
freq. Both can be expressed
in terms of the resistance (R), inductance (L),
conductance (G), and capacitance
(C) per unit length (meters) as follows:
In these equations:
w is the plate width.
d is the plate separation.
σcond is the conductivity in the conductor.
μ is the permeability of the dielectric.
ε is the permittivity of the dielectric.
ε″ is the imaginary part of ε, ε″ = ε0εrtan δ, where:
ε0 is the permittivity of free space.
EpsilonR property value.
tan δ is
LossTangent property value.
δcond is the skin depth of the conductor, which the block calculates as .
f is a vector of modeling frequencies determined by the Outport block.
If you model the transmission line as a shunt or series stub,
analyze method first calculates
the ABCD-parameters at the specified frequencies. It then uses the
abcd2s function to convert the ABCD-parameters
When you set the
'Shunt', the 2-port network
consists of a stub transmission line that you can terminate with either
a short circuit or an open circuit as shown in the following figure.
Zin is the input impedance of the shunt circuit. The ABCD-parameters for the shunt stub are calculated as:
When you set the
'Series', the 2-port network
consists of a series transmission line that you can terminate with
either a short circuit or an open circuit as shown in the following
Zin is the input impedance of the series circuit. The ABCD-parameters for the series stub are calculated as:
analyze method uses
the S-parameters to calculate the group delay values at the frequencies
specified in the
freq, as described in
tx1 = rfckt.twowire; analyze(tx1,[1e9,2e9,3e9]); tx1.AnalyzedResult ans = Name: 'Data object' Freq: [3x1 double] S_Parameters: [2x2x3 double] GroupDelay: [3x1 double] NF: [3x1 double] OIP3: [3x1 double] Z0: 50 ZS: 50 ZL: 50 IntpType: 'Linear'