optic.models.perturbation.calcNLINperturbation

calcNLINperturbation(C_ifwm, C_ixpm, C_ispm, x, y, prec=<class 'numpy.complex64'>)

Fast calculation of the first-order perturbation model.

Parameters:

  • C_ifwm (ndarray of shape (2L+1, 2L+1)) – Nonlinear coefficient matrix for intrachannel four-wave mixing (IFWM).

  • C_ixpm (ndarray of shape (2L+1, 2L+1)) – Nonlinear coefficient matrix for intrachannel cross-phase modulation (IXPM).

  • C_ispm (float) – Scalar nonlinear coefficient for intrachannel self-phase modulation (SPM).

  • x (ndarray of shape (N,)) – Input signal for polarization X (complex-valued).

  • y (ndarray of shape (N,)) – Input signal for polarization Y (complex-valued).

  • prec (data-type, optional) – Precision of the computation (np.complex64 or np.complex128), by default np.complex64.

Returns:

  • dx (ndarray of shape (N,)) – Nonlinear perturbation waveform for polarization X.

  • dy (ndarray of shape (N,)) – Nonlinear perturbation waveform for polarization Y.

  • phi_ixpm_x (ndarray of shape (N,)) – Phase rotation due to cross-phase modulation affecting polarization X.

  • phi_ixpm_y (ndarray of shape (N,)) – Phase rotation due to cross-phase modulation affecting polarization Y.

References

[1] Z. Tao, et al., “Analytical Intrachannel Nonlinear Models to Predict the Nonlinear Noise Waveform,” Journal of Lightwave Technology, vol. 33, no. 10, pp. 2111-2119, 2015.

[2] E. P. da Silva, et al., “Perturbation-Based FEC-Assisted Iterative Nonlinearity Compensation for WDM Systems,” Journal of Lightwave Technology, vol. 37, no. 3, pp. 875-881, 2019.