Paper
5 February 2013 Performance comparison of RZ pulse formats in PDM-16QAM high rates transmissions with optical pre-filtering
E. P Silva, L. H. H. Carvalho, M. L. Lopes, V. B. Ribeiro, A. C. Bordonalli, J. C. R. F. Oliveira
Author Affiliations +
Abstract
The digitally modulated signals spectral density depends directly on pulse format used for information symbols transmission. The modulated signal spectral occupancy can be modified according to the channel frequency response to facilitate information retrieval at the receiver. New generation of coherent optical transmission systems operating at high rates are subject to various bandwidth restrictions aspects, such as electronic components limitations and optical filtering via ROADMs deployed on networks. As noted in technical literature, the RZ pulse formats have some advantages compared to traditional NRZ pulses in optical fiber transmissions. In particular, RZ pulses have a better performance in situations where nonlinear effects of the fiber severely impact the quality of transmission. Among other situations, this occurs in systems that employ modulation formats for high order QAM (16QAM, 64QAM, etc.). Moreover, since RZ pulses have shorter duty cycle, temporal spread of the transmitted symbols causes less performance degradation due to ISI compared with NRZ pulses. This report presents results of experiments carried out in a 226 km recirculation loop, to evaluate the performance of NRZ, RZ 67%, 50% RZ and RZ 33% pulse shapes in a transmission of DP-16QAM (or PDM-16QAM). As application it is proposed and experimentally demonstrated a transmission system that employ 28 GBaud dual carrier PDM-16QAM channels operating with a total line rate of 448 Gb/s each, utilizing RZ pulse format and carrier narrow pre-filtering to increase spectral efficiency of transmission, aggregating a 400G channel in a 75 GHz WDM grid.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
E. P Silva, L. H. H. Carvalho, M. L. Lopes, V. B. Ribeiro, A. C. Bordonalli, and J. C. R. F. Oliveira "Performance comparison of RZ pulse formats in PDM-16QAM high rates transmissions with optical pre-filtering", Proc. SPIE 8647, Next-Generation Optical Communication: Components, Sub-Systems, and Systems II, 86470L (5 February 2013); https://doi.org/10.1117/12.2004974
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Modulation

Wavelength division multiplexing

Optical filters

Pulse shaping

Transmitters

Receivers

Forward error correction

RELATED CONTENT

100G and beyond: optical transmission activities in Brazil
Proceedings of SPIE (January 24 2012)
Transmission of 1 Tb s unique word DFT spread OFDM...
Proceedings of SPIE (December 14 2011)
Design issues of 40 Gbit s WDM systems for metro...
Proceedings of SPIE (February 11 2005)
8x622Mb/s HD-WDM optical fiber transmission over 420 km
Proceedings of SPIE (September 20 1996)
200 Mb s packet switched WDM SCM network using fast...
Proceedings of SPIE (December 17 1992)

Back to Top