optic.models.perturbation.calcNLINperturbationSimplified

calcNLINperturbationSimplified(C_ifwm, C_ixpm, C_ispm, x, y, coeffTol=-20, prec=<class 'numpy.complex64'>)

Fast calculation of the first-order perturbation model with reduced number of coefficients.

Parameters:

  • C_ifwm (ndarray of shape (M,)) – Coefficient matrix for the Inverse Fourier-weighted filter model.

  • C_ixpm (ndarray of shape (M,)) – Coefficient matrix for the Inverse XPM model.

  • C_ispm (scalar) – Coefficient for the Inverse Single-Phase Modulation model.

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

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

  • coeffTol (float) – Coefficient magnitude tolerance in dB. Coefficients with a magnitude below this threshold (in dB) are excluded from the calculation to reduce computational complexity. Default is -20 dB.

  • prec (dtype, optional) – The precision of the computation. Default is np.complex64.

Returns:

  • dx (ndarray of shape (N,)) – The computed result for the X component after processing.

  • dy (ndarray of shape (N,)) – The computed result for the Y component after processing.

  • phi_ixpm_x (ndarray of shape (N,)) – Phase information related to the XPM effect on the X component.

  • phi_ixpm_y (ndarray of shape (N,)) – Phase information related to the XPM effect on the Y component.

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.