skrf.network.Network

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

A n-port electrical network.

For instructions on how to create Network see __init__(). A 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 (str) –

• s_def (str) –

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_opt	the optimum source reflection coefficient to minimize noise
group_delay	The 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.
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
noise_interp_kind	Default interpolation method.
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_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.
s11	one-port sub-network.
s12	one-port sub-network.
s13	one-port sub-network.
s1_1	one-port sub-network.
s1_2	one-port sub-network.
s1_3	one-port sub-network.
s21	one-port sub-network.
s22	one-port sub-network.
s23	one-port sub-network.
s2_1	one-port sub-network.
s2_2	one-port sub-network.
s2_3	one-port sub-network.
s31	one-port sub-network.
s32	one-port sub-network.
s33	one-port sub-network.
s3_1	one-port sub-network.
s3_2	one-port sub-network.
s3_3	one-port sub-network.
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 parameters
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
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	adds a flatband complex zero-mean gaussian white-noise signal of given standard deviations for magnitude and phase
copy	Returns a copy of this Network
copy_from	Copies the contents of another Network into self
copy_subset	Returns 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	Swaps the ports of a 2n-port Network (inplace).
flipped	Returns a flipped network, leaves self alone.
from_z	Create a Network from its Z-parameters
func_on_parameter	Applies a function parameter matrix, one frequency slice at a time
gmm2se	Transform network from generalized mixed mode parameters [#]_ to single ended parameters
impulse_response	Calculates 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	Returns whether the 2N-port network has n-th order reflection symmetry by checking \(S_{i,i} == S_{j,j}\) for appropriate pair(s) of \(i\) and \(j\).
multiply_noise	multiplies 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
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 vs frequency.
plot_a_arcl_unwrap	plot the Network attribute a_arcl_unwrap vs frequency.
plot_a_complex	plot the Network attribute a vs frequency.
plot_a_db	plot the Network attribute a_db vs frequency.
plot_a_db10	plot the Network attribute a_db10 vs frequency.
plot_a_deg	plot the Network attribute a_deg vs frequency.
plot_a_deg_unwrap	plot the Network attribute a_deg_unwrap vs frequency.
plot_a_im	plot the Network attribute a_im vs frequency.
plot_a_mag	plot the Network attribute a_mag vs frequency.
plot_a_polar	plot the Network attribute a vs frequency.
plot_a_rad	plot the Network attribute a_rad vs frequency.
plot_a_rad_unwrap	plot the Network attribute a_rad_unwrap vs frequency.
plot_a_re	plot the Network attribute a_re vs frequency.
plot_a_time	plot the Network attribute a_time vs frequency.
plot_a_time_db	plot the Network attribute a_time_db vs frequency.
plot_a_time_impulse	plot the Network attribute a_time_impulse vs frequency.
plot_a_time_mag	plot the Network attribute a_time_mag vs frequency.
plot_a_time_step	plot the Network attribute a_time_step vs frequency.
plot_a_vswr	plot the Network attribute a_vswr vs frequency.
plot_h_arcl	plot the Network attribute h_arcl vs frequency.
plot_h_arcl_unwrap	plot the Network attribute h_arcl_unwrap vs frequency.
plot_h_complex	plot the Network attribute h vs frequency.
plot_h_db	plot the Network attribute h_db vs frequency.
plot_h_db10	plot the Network attribute h_db10 vs frequency.
plot_h_deg	plot the Network attribute h_deg vs frequency.
plot_h_deg_unwrap	plot the Network attribute h_deg_unwrap vs frequency.
plot_h_im	plot the Network attribute h_im vs frequency.
plot_h_mag	plot the Network attribute h_mag vs frequency.
plot_h_polar	plot the Network attribute h vs frequency.
plot_h_rad	plot the Network attribute h_rad vs frequency.
plot_h_rad_unwrap	plot the Network attribute h_rad_unwrap vs frequency.
plot_h_re	plot the Network attribute h_re vs frequency.
plot_h_time	plot the Network attribute h_time vs frequency.
plot_h_time_db	plot the Network attribute h_time_db vs frequency.
plot_h_time_impulse	plot the Network attribute h_time_impulse vs frequency.
plot_h_time_mag	plot the Network attribute h_time_mag vs frequency.
plot_h_time_step	plot the Network attribute h_time_step vs frequency.
plot_h_vswr	plot the Network attribute h_vswr vs frequency.
plot_it_all	Plot dB, deg, smith, and complex in subplots.
plot_passivity	Plot dB(diag(passivity metric)) vs frequency.
plot_reciprocity	Plot reciprocity metric.
plot_reciprocity2	Plot reciprocity metric #2.
plot_s_arcl	plot the Network attribute s_arcl vs frequency.
plot_s_arcl_unwrap	plot the Network attribute s_arcl_unwrap vs frequency.
plot_s_complex	plot the Network attribute s vs frequency.
plot_s_db	plot the Network attribute s_db vs frequency.
plot_s_db10	plot the Network attribute s_db10 vs frequency.
plot_s_db_time
plot_s_deg	plot the Network attribute s_deg vs frequency.
plot_s_deg_unwrap	plot the Network attribute s_deg_unwrap vs frequency.
plot_s_im	plot the Network attribute s_im vs frequency.
plot_s_mag	plot the Network attribute s_mag vs frequency.
plot_s_polar	plot the Network attribute s vs frequency.
plot_s_rad	plot the Network attribute s_rad vs frequency.
plot_s_rad_unwrap	plot the Network attribute s_rad_unwrap vs frequency.
plot_s_re	plot the Network attribute s_re vs frequency.
plot_s_smith	plots the scattering parameter on a smith chart
plot_s_time	plot the Network attribute s_time vs frequency.
plot_s_time_db	plot the Network attribute s_time_db vs frequency.
plot_s_time_impulse	plot the Network attribute s_time_impulse vs frequency.
plot_s_time_mag	plot the Network attribute s_time_mag vs frequency.
plot_s_time_step	plot the Network attribute s_time_step vs frequency.
plot_s_vswr	plot the Network attribute s_vswr vs frequency.
plot_t_arcl	plot the Network attribute t_arcl vs frequency.
plot_t_arcl_unwrap	plot the Network attribute t_arcl_unwrap vs frequency.
plot_t_complex	plot the Network attribute t vs frequency.
plot_t_db	plot the Network attribute t_db vs frequency.
plot_t_db10	plot the Network attribute t_db10 vs frequency.
plot_t_deg	plot the Network attribute t_deg vs frequency.
plot_t_deg_unwrap	plot the Network attribute t_deg_unwrap vs frequency.
plot_t_im	plot the Network attribute t_im vs frequency.
plot_t_mag	plot the Network attribute t_mag vs frequency.
plot_t_polar	plot the Network attribute t vs frequency.
plot_t_rad	plot the Network attribute t_rad vs frequency.
plot_t_rad_unwrap	plot the Network attribute t_rad_unwrap vs frequency.
plot_t_re	plot the Network attribute t_re vs frequency.
plot_t_time	plot the Network attribute t_time vs frequency.
plot_t_time_db	plot the Network attribute t_time_db vs frequency.
plot_t_time_impulse	plot the Network attribute t_time_impulse vs frequency.
plot_t_time_mag	plot the Network attribute t_time_mag vs frequency.
plot_t_time_step	plot the Network attribute t_time_step vs frequency.
plot_t_vswr	plot the Network attribute t_vswr vs frequency.
plot_y_arcl	plot the Network attribute y_arcl vs frequency.
plot_y_arcl_unwrap	plot the Network attribute y_arcl_unwrap vs frequency.
plot_y_complex	plot the Network attribute y vs frequency.
plot_y_db	plot the Network attribute y_db vs frequency.
plot_y_db10	plot the Network attribute y_db10 vs frequency.
plot_y_deg	plot the Network attribute y_deg vs frequency.
plot_y_deg_unwrap	plot the Network attribute y_deg_unwrap vs frequency.
plot_y_im	plot the Network attribute y_im vs frequency.
plot_y_mag	plot the Network attribute y_mag vs frequency.
plot_y_polar	plot the Network attribute y vs frequency.
plot_y_rad	plot the Network attribute y_rad vs frequency.
plot_y_rad_unwrap	plot the Network attribute y_rad_unwrap vs frequency.
plot_y_re	plot the Network attribute y_re vs frequency.
plot_y_time	plot the Network attribute y_time vs frequency.
plot_y_time_db	plot the Network attribute y_time_db vs frequency.
plot_y_time_impulse	plot the Network attribute y_time_impulse vs frequency.
plot_y_time_mag	plot the Network attribute y_time_mag vs frequency.
plot_y_time_step	plot the Network attribute y_time_step vs frequency.
plot_y_vswr	plot the Network attribute y_vswr vs frequency.
plot_z_arcl	plot the Network attribute z_arcl vs frequency.
plot_z_arcl_unwrap	plot the Network attribute z_arcl_unwrap vs frequency.
plot_z_complex	plot the Network attribute z vs frequency.
plot_z_db	plot the Network attribute z_db vs frequency.
plot_z_db10	plot the Network attribute z_db10 vs frequency.
plot_z_deg	plot the Network attribute z_deg vs frequency.
plot_z_deg_unwrap	plot the Network attribute z_deg_unwrap vs frequency.
plot_z_im	plot the Network attribute z_im vs frequency.
plot_z_mag	plot the Network attribute z_mag vs frequency.
plot_z_polar	plot the Network attribute z vs frequency.
plot_z_rad	plot the Network attribute z_rad vs frequency.
plot_z_rad_unwrap	plot the Network attribute z_rad_unwrap vs frequency.
plot_z_re	plot the Network attribute z_re vs frequency.
plot_z_time	plot the Network attribute z_time vs frequency.
plot_z_time_db	plot the Network attribute z_time_db vs frequency.
plot_z_time_impulse	plot the Network attribute z_time_impulse vs frequency.
plot_z_time_mag	plot the Network attribute z_time_mag vs frequency.
plot_z_time_step	plot the Network attribute z_time_step vs frequency.
plot_z_vswr	plot the Network attribute z_vswr vs frequency.
read	Read a Network from a 'ntwk' file
read_touchstone	loads values from a touchstone file.
renormalize	Renormalize s-parameter matrix given a new port impedances.
renumber	Renumbers ports of a Network (inplace).
renumbered	Returns 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.
se2gmm	Transform network from single ended parameters to generalized mixed mode parameters [#]_
set_noise_a	sets the "A" (ie cascade) representation of the correlation matrix, based on the noise frequency and input parameters.
step_response	Calculates time-domain step response of one-port.
subnetwork	Returns 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	Returns 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	Returns the active Y-parameters of the network for a defined wave excitation a.
z_active	Returns 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