Abstract
We assess numerically the performance of single-carrier digital
backpropagation (SC-DBP) and maximum-likelihood sequence detection
(MLSD) for DP-QPSK and DP-16QAM superchannel transmission over
dispersion uncompensated links for three different cases of spectral shaping:
optical pre-filtering of RZ and NRZ spectra, and digital Nyquist filtering.
We investigate the limits for carrier proximity of each spectral shaping
technique and the correspondent performance behavior of each algorithm,
for both modulation formats. For superchannels with carrier spacing close to
the Nyquist limit, it is shown that the maximum performance improvement
of 1.0 dB in Q
2
-factor is provided by those algorithms. However, such gain
can be highly reduced when the order of the modulation format increases
Original language | English |
---|---|
Journal | Optics Express |
Volume | 23 |
Issue number | 23 |
Pages (from-to) | 29493-29501 |
ISSN | 1094-4087 |
DOIs | |
Publication status | Published - 2015 |