DocumentCode :
1342140
Title :
Comparison between NRZ and RZ signal formats for in-line amplifier transmission in the zero-dispersion regime
Author :
Matsuda, Toshiya ; Naka, Akira ; Saito, Shigeru
Author_Institution :
NTT Opt. Network Syst. Labs., Yokosuka, Japan
Volume :
16
Issue :
3
fYear :
1998
fDate :
3/1/1998 12:00:00 AM
Firstpage :
340
Lastpage :
348
Abstract :
Nonreturn-to-zero (NRZ) and return-to-zero (RZ) signal formats are experimentally and numerically compared for single-channel long-distance transmission in an in-line amplifier system with dispersion management providing average zero dispersion and local nonzero dispersion at an interval equal to the in-line amplifier spacing. Among a 20-ps RZ signal, a 40-ps RZ signal, and an NRZ signal transmitted in 10 Gb/s straight-line experiments, the last signal achieves the longest transmission distance of 6000 km while the others are limited to 4400 km. Numerical simulations explain these results well and show that, along with linear amplified spontaneous emission (ASE) accumulation, signal waveform distortion due to the combined effect of higher order group-velocity dispersion (GVD) and self-phase modulation (SPM) dominates the performance. Nonlinear optical noise enhancement is not obvious because of the fiber dispersion arrangement. Signals with large pulse widths are less affected by the combined effect, while small-width signals yield superior initial signal-to-noise ratio (SNR) as determined by optical noise. A detailed simulation indicates that a pulse width of about 60 ps is optimum for long distance transmission under the fiber dispersion arranged in this paper
Keywords :
optical fibre communication; optical fibre dispersion; optical noise; superradiance; 10 Gbit/s; 20 ps; 40 ps; 4400 km; 6000 km; NRZ signal formats; RZ signal formats; dispersion management; group-velocity dispersion; in-line amplifier spacing; in-line amplifier transmission; large pulse widths; local nonzero dispersion; nonlinear optical noise enhancement; optical fibre communication; self-phase modulation; signal waveform distortion; single-channel long-distance transmission; zero-dispersion regime; Nonlinear distortion; Numerical simulation; Optical amplifiers; Optical distortion; Optical noise; Optical pulses; Optical signal processing; Signal to noise ratio; Space vector pulse width modulation; Spontaneous emission;
fLanguage :
English
Journal_Title :
Lightwave Technology, Journal of
Publisher :
ieee
ISSN :
0733-8724
Type :
jour
DOI :
10.1109/50.661359
Filename :
661359
Link To Document :
بازگشت