skrf.media.freespace.Freespace

class skrf.media.freespace.Freespace(frequency=None, z0_port=None, z0_override=None, z0=None, ep_r=1 + 0j, mu_r=1 + 0j, ep_loss_tan=None, mu_loss_tan=None, rho=None, *args, **kwargs)

A plane-wave (TEM Mode) in Freespace.

A Freespace media can be constructed in two ways:

• from complex, relative permativity and permeability OR

• from real relative permativity and permeability with loss tangents.

There is also a method to initialize from a existing distributed circuit, appropriately named Freespace.from_distributed_circuit()

Parameters:

• frequency (Frequency object) – frequency band of this transmission line medium

• z0_port (number, array-like, or None) – z0_port is the port impedance for networks generated by the media. If z0_port is not None, the networks generated by the media are renormalized (or in other words embedded) from the characteristic impedance z0 of the media to z0_port. Else if z0_port is None, the networks port impedances will be the raw characteristic impedance z0 of the media. (Default is None)

• z0_override (number, array-like, or None) – z0_override override the characteristic impedance for the media. If z0_override is not None, the networks generated by the media have their characteristic impedance z0 overrided by z0_override. (Default is None)

• z0 (number, array-like, or None) – deprecated parameter, alias to z0_override if z0_override is None. Emmit a deprecation warning.

• ep_r (number, array-like) – complex relative permittivity. negative imaginary is lossy.

• mu_r (number, array-like) – complex relative permeability. negative imaginary is lossy.

• ep_loss_tan (None, number, array-like) – electric loss tangent (of the permativity). If not None, imag(ep_r) is ignored.

• mu_loss_tan (None, number, array-like) – magnetic loss tangent (of the permeability). If not None, imag(mu_r) is ignored.

• rho (number, array-like, string or None) – resistivity (ohm-m) of the conductor walls. If array-like must be same length as frequency. if str, it must be a key in skrf.data.materials. Default is None (lossless).

• *args (arguments and keyword arguments)

• **kwargs (arguments and keyword arguments)

Examples

>>> from skrf.media.freespace import Freespace
>>> from skrf.frequency import Frequency
>>> f = Frequency(75,110,101,'ghz')
>>> Freespace(frequency=f, ep_r=11.9)
>>> Freespace(frequency=f, ep_r=11.9-1.1j)
>>> Freespace(frequency=f, ep_r=11.9, ep_loss_tan=.1)
>>> Freespace(frequency=f, ep_r=11.9-1.1j, mu_r = 1.1-.1j)

Attributes

Z0	Characteristic Impedance
alpha	Real (attenuation) component of gamma.
beta	Imaginary (propagating) component of gamma.
ep	Complex dielectric permittivity.
ep_with_rho	Complex permittivity with resistivity absorbed into its imaginary component.
gamma	Propagation Constant, \(\gamma\).
mu	Complex dielectric permeability.
npoints	Number of points of the frequency axis.
rho	Conductivity in ohm*m.
v_g	Complex group velocity (in m/s).
v_p	Complex phase velocity (in m/s).
z0	Return Characteristic Impedance z0_characteristic.
z0_characteristic	Characteristic Impedance, \(z_0\).
z0_override	Port Impedance.
z0_port	Port Impedance.

Methods

__init__
attenuator	Ideal matched attenuator of a given length.
capacitor	Capacitor.
capacitor_q	Capacitor with Q factor.
copy	Copy of this Media object.
delay_load	Delayed load.
delay_open	Delayed open transmission line.
delay_short	Delayed Short.
electrical_length	Calculate the complex electrical length for a given distance.
extract_distance	Determines physical distance from a transmission or reflection Network.
from_distributed_circuit	Initialize a freespace from DistributedCircuit.
get_array_of
impedance_mismatch	Two-port network for an impedance mismatch.
inductor	Inductor.
inductor_q	Inductor with Q factor.
isolator	Two-port isolator.
line	Transmission line of a given length and impedance.
load	Load of given reflection coefficient.
lossless_mismatch	Lossless, symmetric mismatch defined by its return loss.
match	Perfect matched load (\(\Gamma_0 = 0\)).
mode	Create another mode in this medium.
open	Open (\(\Gamma_0 = 1\)).
plot
plot_ep	Plot the real and imaginary part of the complex permittivity.
plot_ep_mu	Plot the real and imaginary part of the complex permittivity with resistivity.
plot_mu	Plot the real and imaginary part of the complex permeability.
random	Complex random network.
resistor	Resistor.
short	Short (\(\Gamma_0 = -1\))
shunt	Shunts a Network.
shunt_capacitor	Shunted capacitor.
shunt_delay_load	Shunted delayed load.
shunt_delay_open	Shunted delayed open.
shunt_delay_short	Shunted delayed short.
shunt_inductor	Shunted inductor.
shunt_resistor	Shunted resistor.
splitter	Ideal, lossless n-way splitter.
tee	Ideal, lossless tee.
theta_2_d	Convert electrical length to physical distance.
thru	Matched transmission line of length 0.
to_meters	Translate various units of distance into meters.
white_gaussian_polar	Complex zero-mean gaussian white-noise network.
write_csv	write this media's frequency, gamma, Z0, and z0 to a csv file.