Mitigation of intra-channel nonlinearities using a frequency-domain Volterra series equalizer
Guiomar, F. P.
; Reis, J.D.
Pinto, A. N.
Optics Express Vol. 20, Nº 2, pp. 1360 - 1369, January, 2012.
ISSN (print): 1094-4087
Scimago Journal Ranking: 2,56 (in 2012)
Digital Object Identifier: 10.1364/OE.20.001360
We address the issue of intra-channel nonlinear compensation
using a Volterra series nonlinear equalizer based on an analytical closed-form solution for the 3rd order Volterra kernel in frequency-domain. The performance of the method is investigated through numerical simulations for a single-channel optical system using a 20 Gbaud NRZ-QPSK test signal propagated over 1600 km of both standard single-mode fiber and non-zero dispersion shifted fiber. We carry on performance and computational effort comparisons with the well-known backward propagation split-step Fourier (BP-SSF) method. The alias-free frequency-domain implementation of the Volterra series nonlinear equalizer makes it an attractive approach to work at low sampling rates, enabling to surpass the maximum performance of BP-SSF at 2x oversampling. Linear and nonlinear equalization can be treated independently, providing more flexibility to the equalization subsystem. The parallel structure of the algorithm is also a key advantage in
terms of real-time implementation.