skrf.media.coaxial.Coaxial

class skrf.media.coaxial.Coaxial(frequency=None, z0_port=None, z0_override=None, z0=None, Dint=0.00081, Dout=0.005, epsilon_r=1, tan_delta=0, sigma=1e+99, *args, **kwargs)[source]

A coaxial transmission line defined in terms of its inner/outer diameters and permittivity.

Parameters:
  • frequency (Frequency object) – Frequency band.

  • 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.

  • Dint (number, or array-like) – inner conductor diameter, in m

  • Dout (number, or array-like) – outer conductor diameter, in m

  • epsilon_r (number, or array-like, optional) – relative permittivity of the dielectric medium. Default is 1.

  • tan_delta (number, or array-like, optional) – loss tangent of the dielectric medium. Default is 0.

  • sigma (number, or array-like, optional.) – conductors electrical conductivity, in S/m. Default is infinity (non lossy metal).

TODO : different conductivity in case of different conductor kind

Note

Dint, Dout, epsilon_r, tan_delta, sigma can all be vectors as long as they are the same length

References

Attributes

C

Distributed capacitance C, in F/m

G

Distributed conductance G, in S/m

L

Distributed inductance L, in H/m

R

Distributed resistance R, in Ohm/m.

Rs

Surface resistivity in Ohm/area.

Y

Distributed Admittance, \(Y^{'}\).

Z

Distributed Impedance, \(Z^{'}\).

Z0

Characteristic Impedance

a

Inner radius of the coaxial line

alpha

Real (attenuation) component of gamma.

b

Outer radius of the coaxial line

beta

Imaginary (propagating) component of gamma.

gamma

Propagation Constant, \(\gamma\).

npoints

Number of points of the frequency axis.

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_Z0_Dout

Init from characteristic impedance and outer diameter.

from_attenuation_VF

Init from electrical properties of the line: attenuation and velocity factor.

from_csv

Create a DistributedCircuit from numerical values stored in a csv file.

from_media

Initializes a DistributedCircuit from an existing Media instance.

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

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.