skrf.media.circularWaveguide.CircularWaveguide

class skrf.media.circularWaveguide.CircularWaveguide(frequency=None, z0=None, r=1, mode_type='te', m=1, n=1, ep_r=1, mu_r=1, rho=None, *args, **kwargs)

A single mode of a homogeneously filled Circular Waveguide

Represents a single mode of a homogeneously filled circular waveguide of cross-section r^2 pi. The mode is determined by mode-type (‘te’ or ‘tm’) and mode indices ( m and n ). Corrugated circular waveguides, which also support HE modes, are not supported.

Quantity	Symbol	Variable
Characteristic Wave Number	\(k_0\)	k0
Cut-off Wave Number	\(k_c\)	kc
Longitudinal Wave Number	\(k_z\)	gamma
Transverse Wave Number (a)	\(k_x\)	kx
Transverse Wave Number (b)	\(k_y\)	ky
Characteristic Impedance	\(z_0\)	z0

Parameters

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

• z0 (number, array-like, or None) – the port impedance for media. Only needed if it’s different from the characteristic impedance of the transmission line. if z0 is None then will default to Z0

• r (number) – radius of the waveguide, in meters.

• mode_type (['te','tm']) – mode type, transverse electric (te) or transverse magnetic (tm) to-z. where z is direction of propagation

• m (int) – mode index in ‘phi’-direction, the azimuthal index

• n (int) – mode index in ‘r’-direction, the radial index

• ep_r (number, array-like,) – filling material’s relative permittivity

• mu_r (number, array-like) – filling material’s relative permeability

• rho (number, array-like, string) – 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.

• *args (arguments, keyword arguments) – passed to Media’s constructor (__init__()

• **kwargs (arguments, keyword arguments) – passed to Media’s constructor (__init__()

Examples

In the following example an ideal waveguide of 2.39 mm diameter is constructed for the high W band, operated in the fundamental TE11 mode. If no conductivity is provided the walls are treated as perfect electric conductors.

>>> freq = rf.Frequency(88, 110, 101, 'ghz')
>>> rf.CircularWaveguide(freq, r=0.5 * 2.39e-3)

Attributes

Z0	The characteristic impedance.
alpha	Real (attenuation) component of gamma.
alpha_c	Loss due to finite conductivity of the sidewalls for the fundamental mode TE11.
beta	Imaginary (propagating) component of gamma.
ep	The permativity of the filling material.
f_cutoff	cutoff frequency for this mode
f_norm	frequency vector normalized to cutoff
gamma	The propagation constant (aka Longitudinal wave number)
k0	Characteristic wave number.
kc	Cut-off wave number.
lambda_cutoff	Cutoff wavelength.
lambda_guide	Guide wavelength.
mu	The permeability of the filling material.
npoints	Number of points of the frequency axis.
rho	conductivity of sidewalls in ohm*m
v_g	Complex group velocity (in m/s).
v_p	Complex phase velocity (in m/s).
z0	Characteristic Impedance.

Methods

__init__
attenuator	Ideal matched attenuator of a given length.
capacitor	Capacitor.
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	Initialize from specified impedance at a given frequency, assuming the fundamental TE11 mode.
get_array_of
impedance_mismatch	Two-port network for an impedance mismatch.
inductor	Inductor.
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.
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.