# skrf.tlineFunctions.reflection_coefficient_2_propagation_constant¶

skrf.tlineFunctions.reflection_coefficient_2_propagation_constant(Gamma_in, Gamma_l, d)[source]

Propagation constant from line input and load reflection coefficients.

Calculate the propagation constant of a line of length d, given the reflection coefficient and characteristic impedance of the medium.

$\Gamma_{in} = \Gamma_l e^{-2 j \gamma \cdot d} \to \gamma = -\frac{1}{2 d} \ln \left ( \frac{ \Gamma_{in} }{ \Gamma_l } \right )$
Parameters
• Gamma_in (number or array-like) – input reflection coefficient

• Gamma_l (number or array-like) – load reflection coefficient

• d (number or array-like) – length of line, in meters

Returns

gamma – propagation constant (see notes)

Return type

number (complex) or array-like

Note

The convention has been chosen that forward propagation is represented by the positive imaginary part of gamma.