skrf.network.Network

class skrf.network.Network(file=None, name=None, params=None, comments=None, f_unit=None, s_def=None, **kwargs)

An n-port electrical network.

For instructions on how to create Network see __init__(). An n-port network [1] may be defined by three quantities

• network parameter matrix (s, z, or y-matrix)

• port characteristic impedance matrix

• frequency information

The Network class stores these data structures internally in the form of complex numpy.ndarray’s. These arrays are not interfaced directly but instead through the use of the properties:

Property	Meaning
s	Scattering parameter matrix.
z0	Characteristic impedance matrix.
f	Frequency vector.

Although these docs focus on s-parameters, other equivalent network representations such as z and y are available. Scalar projections of the complex network parameters are accessible through properties as well. These also return numpy.ndarray’s.

Property	Meaning
s_re	Real part of the s-matrix.
s_im	Imaginary part of the s-matrix.
s_mag	Magnitude of the s-matrix.
s_db	Magnitude in log scale of the s-matrix.
s_deg	Phase of the s-matrix in degrees.

The following operations act on the networks s-matrix.

Operator	Function
+	Element-wise addition of the s-matrix.
-	Element-wise difference of the s-matrix.
*	Element-wise multiplication of the s-matrix.
/	Element-wise division of the s-matrix.
**	Cascading (only for 2-ports).
//	De-embedding (for 2-ports, see inv).

Different components of the Network can be visualized through various plotting methods. These methods can be used to plot individual elements of the s-matrix or all at once. For more info about plotting see the Plotting tutorial.

Method	Meaning
plot_s_smith()	Plot complex s-parameters on smith chart.
plot_s_re()	Plot real part of s-parameters vs frequency.
plot_s_im()	Plot imaginary part of s-parameters vs frequency.
plot_s_mag()	Plot magnitude of s-parameters vs frequency.
plot_s_db()	Plot magnitude (in dB) of s-parameters vs frequency.
plot_s_deg()	Plot phase of s-parameters (in degrees) vs frequency.
plot_s_deg_unwrap()	Plot phase of s-parameters (in unwrapped degrees) vs frequency.

Network objects can be created from a touchstone or pickle file (see __init__()), by a Media object, or manually by assigning the network properties directly. Network objects can be saved to disk in the form of touchstone files with the write_touchstone() method.

An exhaustive list of Network Methods and Properties (Attributes) are given below

References

[1]

http://en.wikipedia.org/wiki/Two-port_network

Parameters:

• file (str)

• name (str)

• params (dict)

• comments (str)

• f_unit (FrequencyUnitT | None)

• s_def (SdefT | None)

Attributes

COMPONENT_FUNC_DICT	Component functions like 're', 'im', 'mag', 'db', etc.
PRIMARY_PROPERTIES	Primary Network Properties list like 's', 'z', 'y', etc.
Y_LABEL_DICT	Y-axis labels to the plotting functions.
a	abcd parameter matrix.
a_arcl	The arcl component of the a-matrix.
a_arcl_unwrap	The arcl_unwrap component of the a-matrix.
a_db	The db component of the a-matrix.
a_db10	The db10 component of the a-matrix.
a_deg	The deg component of the a-matrix.
a_deg_unwrap	The deg_unwrap component of the a-matrix.
a_im	The im component of the a-matrix.
a_mag	The mag component of the a-matrix.
a_rad	The rad component of the a-matrix.
a_rad_unwrap	The rad_unwrap component of the a-matrix.
a_re	The re component of the a-matrix.
a_time	The time component of the a-matrix.
a_time_db	The time_db component of the a-matrix.
a_time_impulse	The time_impulse component of the a-matrix.
a_time_mag	The time_mag component of the a-matrix.
a_time_step	The time_step component of the a-matrix.
a_vswr	The vswr component of the a-matrix.
f	The frequency vector for the network, in Hz.
f_noise	The frequency vector for the noise of the network, in Hz.
frequency	Frequency information for the network.
g	Inverse hybrid parameter matrix.
g_arcl	The arcl component of the g-matrix.
g_arcl_unwrap	The arcl_unwrap component of the g-matrix.
g_db	The db component of the g-matrix.
g_db10	The db10 component of the g-matrix.
g_deg	The deg component of the g-matrix.
g_deg_unwrap	The deg_unwrap component of the g-matrix.
g_im	The im component of the g-matrix.
g_mag	The mag component of the g-matrix.
g_opt	The optimum source reflection coefficient to minimize noise.
g_rad	The rad component of the g-matrix.
g_rad_unwrap	The rad_unwrap component of the g-matrix.
g_re	The re component of the g-matrix.
g_time	The time component of the g-matrix.
g_time_db	The time_db component of the g-matrix.
g_time_impulse	The time_impulse component of the g-matrix.
g_time_mag	The time_mag component of the g-matrix.
g_time_step	The time_step component of the g-matrix.
g_vswr	The vswr component of the g-matrix.
group_delay	Group delay.
h	Hybrid parameter matrix.
h_arcl	The arcl component of the h-matrix.
h_arcl_unwrap	The arcl_unwrap component of the h-matrix.
h_db	The db component of the h-matrix.
h_db10	The db10 component of the h-matrix.
h_deg	The deg component of the h-matrix.
h_deg_unwrap	The deg_unwrap component of the h-matrix.
h_im	The im component of the h-matrix.
h_mag	The mag component of the h-matrix.
h_rad	The rad component of the h-matrix.
h_rad_unwrap	The rad_unwrap component of the h-matrix.
h_re	The re component of the h-matrix.
h_time	The time component of the h-matrix.
h_time_db	The time_db component of the h-matrix.
h_time_impulse	The time_impulse component of the h-matrix.
h_time_mag	The time_mag component of the h-matrix.
h_time_step	The time_step component of the h-matrix.
h_vswr	The vswr component of the h-matrix.
inv	A Network object with 'inverse' s-parameters.
max_gain	Maximum available power gain for K > 1 and maximum stable power gain for K <= 1 (in linear).
max_stable_gain	Maximum stable power gain [1]_ (in linear).
n	The ABCD form of the noise correlation matrix for the network.
nfmin	The minimum noise figure for the network.
nfmin_db	The minimum noise figure for the network in dB.
noisy	Whether this network has noise.
nports	The number of ports the network has.
number_of_ports	The number of ports the network has.
passivity	Passivity metric for a multi-port network.
port_modes	Array of size nports with the mode of each port.
port_tuples	Returns a list of tuples, for each port index pair.
reciprocity	Reciprocity metric for a multi-port network.
reciprocity2	Reciprocity metric #2
rn	The equivalent noise resistance for the network.
s	Scattering parameter matrix.
s_arcl	The arcl component of the s-matrix.
s_arcl_unwrap	The arcl_unwrap component of the s-matrix.
s_db	The db component of the s-matrix.
s_db10	The db10 component of the s-matrix.
s_deg	The deg component of the s-matrix.
s_deg_unwrap	The deg_unwrap component of the s-matrix.
s_im	The im component of the s-matrix.
s_invert	Inverted scattering parameter matrix.
s_mag	The mag component of the s-matrix.
s_power	Scattering parameter matrix with s_def = 'power'.
s_pseudo	Scattering parameter matrix with s_def = 'pseudo'.
s_rad	The rad component of the s-matrix.
s_rad_unwrap	The rad_unwrap component of the s-matrix.
s_re	The re component of the s-matrix.
s_time	The time component of the s-matrix.
s_time_db	The time_db component of the s-matrix.
s_time_impulse	The time_impulse component of the s-matrix.
s_time_mag	The time_mag component of the s-matrix.
s_time_step	The time_step component of the s-matrix.
s_traveling	Scattering parameter matrix with s_def = 'traveling'.
s_vswr	The vswr component of the s-matrix.
stability	Stability factor.
t	Scattering transfer parameter matrix.
t_arcl	The arcl component of the t-matrix.
t_arcl_unwrap	The arcl_unwrap component of the t-matrix.
t_db	The db component of the t-matrix.
t_db10	The db10 component of the t-matrix.
t_deg	The deg component of the t-matrix.
t_deg_unwrap	The deg_unwrap component of the t-matrix.
t_im	The im component of the t-matrix.
t_mag	The mag component of the t-matrix.
t_rad	The rad component of the t-matrix.
t_rad_unwrap	The rad_unwrap component of the t-matrix.
t_re	The re component of the t-matrix.
t_time	The time component of the t-matrix.
t_time_db	The time_db component of the t-matrix.
t_time_impulse	The time_impulse component of the t-matrix.
t_time_mag	The time_mag component of the t-matrix.
t_time_step	The time_step component of the t-matrix.
t_vswr	The vswr component of the t-matrix.
unilateral_gain	Mason's unilateral power gain [1]_ (in linear).
y	Admittance parameter matrix.
y_arcl	The arcl component of the y-matrix.
y_arcl_unwrap	The arcl_unwrap component of the y-matrix.
y_db	The db component of the y-matrix.
y_db10	The db10 component of the y-matrix.
y_deg	The deg component of the y-matrix.
y_deg_unwrap	The deg_unwrap component of the y-matrix.
y_im	The im component of the y-matrix.
y_mag	The mag component of the y-matrix.
y_opt	The optimum source admittance to minimize noise.
y_rad	The rad component of the y-matrix.
y_rad_unwrap	The rad_unwrap component of the y-matrix.
y_re	The re component of the y-matrix.
y_time	The time component of the y-matrix.
y_time_db	The time_db component of the y-matrix.
y_time_impulse	The time_impulse component of the y-matrix.
y_time_mag	The time_mag component of the y-matrix.
y_time_step	The time_step component of the y-matrix.
y_vswr	The vswr component of the y-matrix.
z	Impedance parameter matrix.
z0	Characteristic impedance[s] of the network ports.
z_arcl	The arcl component of the z-matrix.
z_arcl_unwrap	The arcl_unwrap component of the z-matrix.
z_db	The db component of the z-matrix.
z_db10	The db10 component of the z-matrix.
z_deg	The deg component of the z-matrix.
z_deg_unwrap	The deg_unwrap component of the z-matrix.
z_im	The im component of the z-matrix.
z_mag	The mag component of the z-matrix.
z_opt	The optimum source impedance to minimize noise.
z_rad	The rad component of the z-matrix.
z_rad_unwrap	The rad_unwrap component of the z-matrix.
z_re	The re component of the z-matrix.
z_time	The time component of the z-matrix.
z_time_db	The time_db component of the z-matrix.
z_time_impulse	The time_impulse component of the z-matrix.
z_time_mag	The time_mag component of the z-matrix.
z_time_step	The time_step component of the z-matrix.
z_vswr	The vswr component of the z-matrix.

Methods

__init__	Network constructor.
add_noise_polar	Adds a complex zero-mean gaussian white-noise.
add_noise_polar_flatband	Add a flatband complex zero-mean gaussian white-noise signal of given standard deviations for magnitude and phase.
attribute
copy	Return a copy of this Network.
copy_from	Copy the contents of another Network into self.
copy_subset	Return a copy of a frequency subset of this Network.
crop	Crop Network based on start and stop frequencies.
cropped	Returns a cropped network, leaves self alone.
delay	Add phase delay to a given port.
drop_non_monotonic_increasing	Drop invalid values based on duplicate and non increasing frequency values.
extrapolate_to_dc	Extrapolate S-parameters down to 0 Hz and interpolate to uniform spacing.
flip	Swap the ports of a 2n-port Network (inplace).
flipped	Returns a flipped network, leaves self alone.
from_string	Create a Network object from a text string
from_z	Create a Network from its Z-parameters.
func_on_parameter	Apply a function parameter matrix, one frequency slice at a time.
gain_circle	Returns loci of gain circles for a given port (0 or 1) and a specified gain.
gmm2se	Transform network from generalized mixed mode parameters [#]_ to single ended parameters.
impulse_response	Calculate time-domain impulse response of one-port.
interpolate	Interpolate a Network along frequency axis.
interpolate_self	Interpolate the current Network along frequency axis (inplace).
is_lossless	Test for losslessness.
is_passive	Test for passivity.
is_reciprocal	Test for reciprocity.
is_symmetric	Return whether the 2N-port network has n-th order reflection symmetry by checking.
multiply_noise	Multiply a complex bivariate gaussian white-noise signal of given standard deviations for magnitude and phase.
nf	The noise figure for the network if the source impedance is z.
nf_circle	Returns loci of noise figure circles for a specified noise figure.
nfdb_gs	Return dB(NF) foreach gamma_source x noise_frequency.
nonreciprocity	Normalized non-reciprocity metric.
nudge	Perturb s-parameters by small amount.
plot	Plot something vs frequency
plot_a_arcl	plot the Network attribute a_arcl component vs frequency.
plot_a_arcl_unwrap	plot the Network attribute a_arcl_unwrap component vs frequency.
plot_a_complex	plot the Network attribute {} vs frequency.
plot_a_db	plot the Network attribute a_db component vs frequency.
plot_a_db10	plot the Network attribute a_db10 component vs frequency.
plot_a_deg	plot the Network attribute a_deg component vs frequency.
plot_a_deg_unwrap	plot the Network attribute a_deg_unwrap component vs frequency.
plot_a_im	plot the Network attribute a_im component vs frequency.
plot_a_mag	plot the Network attribute a_mag component vs frequency.
plot_a_polar	plot the Network attribute {} vs frequency.
plot_a_rad	plot the Network attribute a_rad component vs frequency.
plot_a_rad_unwrap	plot the Network attribute a_rad_unwrap component vs frequency.
plot_a_re	plot the Network attribute a_re component vs frequency.
plot_a_time	plot the Network attribute a_time component vs time.
plot_a_time_db	plot the Network attribute a_time_db component vs time.
plot_a_time_impulse	plot the Network attribute a_time_impulse component vs time.
plot_a_time_mag	plot the Network attribute a_time_mag component vs time.
plot_a_time_step	plot the Network attribute a_time_step component vs time.
plot_a_vswr	plot the Network attribute a_vswr component vs frequency.
plot_attribute	plot the Network attribute conversion_attribute component vs frequency or time.
plot_g_arcl	plot the Network attribute g_arcl component vs frequency.
plot_g_arcl_unwrap	plot the Network attribute g_arcl_unwrap component vs frequency.
plot_g_complex	plot the Network attribute {} vs frequency.
plot_g_db	plot the Network attribute g_db component vs frequency.
plot_g_db10	plot the Network attribute g_db10 component vs frequency.
plot_g_deg	plot the Network attribute g_deg component vs frequency.
plot_g_deg_unwrap	plot the Network attribute g_deg_unwrap component vs frequency.
plot_g_im	plot the Network attribute g_im component vs frequency.
plot_g_mag	plot the Network attribute g_mag component vs frequency.
plot_g_polar	plot the Network attribute {} vs frequency.
plot_g_rad	plot the Network attribute g_rad component vs frequency.
plot_g_rad_unwrap	plot the Network attribute g_rad_unwrap component vs frequency.
plot_g_re	plot the Network attribute g_re component vs frequency.
plot_g_time	plot the Network attribute g_time component vs time.
plot_g_time_db	plot the Network attribute g_time_db component vs time.
plot_g_time_impulse	plot the Network attribute g_time_impulse component vs time.
plot_g_time_mag	plot the Network attribute g_time_mag component vs time.
plot_g_time_step	plot the Network attribute g_time_step component vs time.
plot_g_vswr	plot the Network attribute g_vswr component vs frequency.
plot_h_arcl	plot the Network attribute h_arcl component vs frequency.
plot_h_arcl_unwrap	plot the Network attribute h_arcl_unwrap component vs frequency.
plot_h_complex	plot the Network attribute {} vs frequency.
plot_h_db	plot the Network attribute h_db component vs frequency.
plot_h_db10	plot the Network attribute h_db10 component vs frequency.
plot_h_deg	plot the Network attribute h_deg component vs frequency.
plot_h_deg_unwrap	plot the Network attribute h_deg_unwrap component vs frequency.
plot_h_im	plot the Network attribute h_im component vs frequency.
plot_h_mag	plot the Network attribute h_mag component vs frequency.
plot_h_polar	plot the Network attribute {} vs frequency.
plot_h_rad	plot the Network attribute h_rad component vs frequency.
plot_h_rad_unwrap	plot the Network attribute h_rad_unwrap component vs frequency.
plot_h_re	plot the Network attribute h_re component vs frequency.
plot_h_time	plot the Network attribute h_time component vs time.
plot_h_time_db	plot the Network attribute h_time_db component vs time.
plot_h_time_impulse	plot the Network attribute h_time_impulse component vs time.
plot_h_time_mag	plot the Network attribute h_time_mag component vs time.
plot_h_time_step	plot the Network attribute h_time_step component vs time.
plot_h_vswr	plot the Network attribute h_vswr component vs frequency.
plot_it_all	Plot dB, deg, smith, and complex in subplots.
plot_passivity	Plot dB(diag(passivity metric)) vs frequency.
plot_prop_complex	plot the Network attribute {} vs frequency.
plot_prop_polar	plot the Network attribute {} vs frequency.
plot_reciprocity	Plot reciprocity metric.
plot_reciprocity2	Plot reciprocity metric #2.
plot_s_arcl	plot the Network attribute s_arcl component vs frequency.
plot_s_arcl_unwrap	plot the Network attribute s_arcl_unwrap component vs frequency.
plot_s_complex	plot the Network attribute {} vs frequency.
plot_s_db	plot the Network attribute s_db component vs frequency.
plot_s_db10	plot the Network attribute s_db10 component vs frequency.
plot_s_db_time
plot_s_deg	plot the Network attribute s_deg component vs frequency.
plot_s_deg_unwrap	plot the Network attribute s_deg_unwrap component vs frequency.
plot_s_im	plot the Network attribute s_im component vs frequency.
plot_s_mag	plot the Network attribute s_mag component vs frequency.
plot_s_polar	plot the Network attribute {} vs frequency.
plot_s_rad	plot the Network attribute s_rad component vs frequency.
plot_s_rad_unwrap	plot the Network attribute s_rad_unwrap component vs frequency.
plot_s_re	plot the Network attribute s_re component vs frequency.
plot_s_smith	Plots the scattering parameter on a smith chart.
plot_s_time	plot the Network attribute s_time component vs time.
plot_s_time_db	plot the Network attribute s_time_db component vs time.
plot_s_time_impulse	plot the Network attribute s_time_impulse component vs time.
plot_s_time_mag	plot the Network attribute s_time_mag component vs time.
plot_s_time_step	plot the Network attribute s_time_step component vs time.
plot_s_vswr	plot the Network attribute s_vswr component vs frequency.
plot_t_arcl	plot the Network attribute t_arcl component vs frequency.
plot_t_arcl_unwrap	plot the Network attribute t_arcl_unwrap component vs frequency.
plot_t_complex	plot the Network attribute {} vs frequency.
plot_t_db	plot the Network attribute t_db component vs frequency.
plot_t_db10	plot the Network attribute t_db10 component vs frequency.
plot_t_deg	plot the Network attribute t_deg component vs frequency.
plot_t_deg_unwrap	plot the Network attribute t_deg_unwrap component vs frequency.
plot_t_im	plot the Network attribute t_im component vs frequency.
plot_t_mag	plot the Network attribute t_mag component vs frequency.
plot_t_polar	plot the Network attribute {} vs frequency.
plot_t_rad	plot the Network attribute t_rad component vs frequency.
plot_t_rad_unwrap	plot the Network attribute t_rad_unwrap component vs frequency.
plot_t_re	plot the Network attribute t_re component vs frequency.
plot_t_time	plot the Network attribute t_time component vs time.
plot_t_time_db	plot the Network attribute t_time_db component vs time.
plot_t_time_impulse	plot the Network attribute t_time_impulse component vs time.
plot_t_time_mag	plot the Network attribute t_time_mag component vs time.
plot_t_time_step	plot the Network attribute t_time_step component vs time.
plot_t_vswr	plot the Network attribute t_vswr component vs frequency.
plot_y_arcl	plot the Network attribute y_arcl component vs frequency.
plot_y_arcl_unwrap	plot the Network attribute y_arcl_unwrap component vs frequency.
plot_y_complex	plot the Network attribute {} vs frequency.
plot_y_db	plot the Network attribute y_db component vs frequency.
plot_y_db10	plot the Network attribute y_db10 component vs frequency.
plot_y_deg	plot the Network attribute y_deg component vs frequency.
plot_y_deg_unwrap	plot the Network attribute y_deg_unwrap component vs frequency.
plot_y_im	plot the Network attribute y_im component vs frequency.
plot_y_mag	plot the Network attribute y_mag component vs frequency.
plot_y_polar	plot the Network attribute {} vs frequency.
plot_y_rad	plot the Network attribute y_rad component vs frequency.
plot_y_rad_unwrap	plot the Network attribute y_rad_unwrap component vs frequency.
plot_y_re	plot the Network attribute y_re component vs frequency.
plot_y_time	plot the Network attribute y_time component vs time.
plot_y_time_db	plot the Network attribute y_time_db component vs time.
plot_y_time_impulse	plot the Network attribute y_time_impulse component vs time.
plot_y_time_mag	plot the Network attribute y_time_mag component vs time.
plot_y_time_step	plot the Network attribute y_time_step component vs time.
plot_y_vswr	plot the Network attribute y_vswr component vs frequency.
plot_z_arcl	plot the Network attribute z_arcl component vs frequency.
plot_z_arcl_unwrap	plot the Network attribute z_arcl_unwrap component vs frequency.
plot_z_complex	plot the Network attribute {} vs frequency.
plot_z_db	plot the Network attribute z_db component vs frequency.
plot_z_db10	plot the Network attribute z_db10 component vs frequency.
plot_z_deg	plot the Network attribute z_deg component vs frequency.
plot_z_deg_unwrap	plot the Network attribute z_deg_unwrap component vs frequency.
plot_z_im	plot the Network attribute z_im component vs frequency.
plot_z_mag	plot the Network attribute z_mag component vs frequency.
plot_z_polar	plot the Network attribute {} vs frequency.
plot_z_rad	plot the Network attribute z_rad component vs frequency.
plot_z_rad_unwrap	plot the Network attribute z_rad_unwrap component vs frequency.
plot_z_re	plot the Network attribute z_re component vs frequency.
plot_z_time	plot the Network attribute z_time component vs time.
plot_z_time_db	plot the Network attribute z_time_db component vs time.
plot_z_time_impulse	plot the Network attribute z_time_impulse component vs time.
plot_z_time_mag	plot the Network attribute z_time_mag component vs time.
plot_z_time_step	plot the Network attribute z_time_step component vs time.
plot_z_vswr	plot the Network attribute z_vswr component vs frequency.
read	Read a Network from a 'ntwk' file.
read_touchstone	Load values from a touchstone file.
renormalize	Renormalize s-parameter matrix given a new port impedances.
renumber	Renumber ports of a Network (inplace).
renumbered	Return a renumbered Network, leave self alone.
resample	Interpolate the current Network along frequency axis (inplace).
rotate	Rotate S-parameters
s_active	Returns the active s-parameters of the network for a defined wave excitation a.
s_error	Compute the error between s-parameters of this network and another network ntwk.
se2gmm	Transform network from single ended parameters to generalized mixed mode parameters [#]_.
set_noise_a	Set the "A" (ie cascade) representation of the correlation matrix, based on the noise frequency and input parameters.
stability_circle	Returns loci of stability circles for a given port (0 or 1).
step_response	Calculate time-domain step response of one-port.
subnetwork	Return a subnetwork of a the Network from a list of port numbers.
time_gate	Time gate this Network.
to_dataframe	Convert attributes of a Network to a pandas DataFrame.
vswr_active	Return the active VSWR of the network for a defined wave excitation a.
windowed	Return a windowed version of s-matrix.
write	Write the Network to disk using the pickle module.
write_spreadsheet	Write contents of network to a spreadsheet, for your boss to use.
write_to_json_string	Serialize and convert network to a JSON string.
write_touchstone	Write a contents of the Network to a touchstone file.
y_active	Return the active Y-parameters of the network for a defined wave excitation a.
z_active	Return the active Z-parameters of the network for a defined wave excitation a.
zipped_touchstone	Read a Network from a Touchstone file in a ziparchive.