skrf.circuit.Circuit.z_active¶

Circuit.z_active(a)[source]¶

Return the “active” Z-parameters of the circuit’s network for a defined wave excitation a.

The “active” Z-parameters are defined by:

\[\mathrm{active}(z)_{m} = z_{0,m} \frac{1 + \mathrm{active}(s)_m}{1 - \mathrm{active}(s)_m}\]

where \(z_{0,m}\) is the characteristic impedance and \(\mathrm{active}(s)_m\) the active S-parameter of port \(m\).

Parameters:: a (complex array of shape (n_ports)) – forward wave complex amplitude
Returns:: z_act – active Z-parameters for the excitation a
Return type:: complex array of shape (nfreqs, nports)