# skrf.media.freespace.Freespace¶

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

A plane-wave (TEM Mode) in Freespace.

A Freespace media can be constructed in two ways:
• from complex, relative permativity and permiability OR
• from real relative permativity and permiability with loss tangents.

See Examples. 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 (number, array-like, or None) – the port impedance for media. Only needed if its different from the characterisitc impedance of the transmission line. if z0 is None then will default to Z0 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) – the loss tangent of the permativity. If not None, imag(ep_r) is ignored. mu_loss_tan (None, number, array-like) – the loss tangent of the permeability. If not None, imag(mu_r) is ignored. **kwargs (*args,) –

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, $$Z0$$ alpha real (attenuation) component of gamma beta imaginary (propagating) component of gamma ep ep_with_rho complex permativity with resistivity absorbed into its imaginary component gamma Propagation Constant, $$\gamma$$ mu npoints rho conductivty in ohm*m v_g Complex group velocity (in m/s) v_p Complex phase velocity (in m/s) z0

Methods

 __init__ Initialize self. attenuator Ideal matched attenuator of a given length capacitor Capacitor copy delay_load Delayed load delay_open Delayed open transmission line delay_short Delayed Short electrical_length calculates the electrical length for a given distance extract_distance Determines physical distance from a transmission or reflection ntwk from_distributed_circuit initialize a freespace from media.DistributedCirctuit 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 plot_ep plot_ep_mu plot_mu 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 Converts 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.