# skrf.media.cpw.CPW.v_g¶

property CPW.v_g

Complex group velocity (in m/s).

$j \cdot d \omega / d \gamma$

where:

• $$\omega$$ is angular frequency (rad/s),

• $$\gamma$$ is complex propagation constant (rad/m)

Notes

the j is used to make propagation real, this is needed because skrf defined the gamma as $$\gamma= \alpha +j\beta$$.

Returns

v_g

Return type

numpy.ndarray

References

https://en.wikipedia.org/wiki/Group_velocity

propagation_constant, v_p, gamma