In this work we experimentally demonstrate 500 km unrepeatered transmission of a single-channel 100 Gb s −1 dual polarization quadrature phase shift keyed (DP-QPSK) signal. Such long distance transmission is achieved through the use of an advanced configuration of remotely pumped optical amplifiers (ROPAs), chromatic dispersion pre-compensation and ultra-low-loss Corning R SMF-28 R ULL optical fiber. Excellent long-term bit error ratio (BER) performance is observed. To the best of our knowledge this is the longest unrepeatered 100 Gb s −1 transmission reported to date.
In this work we experimentally demonstrate 1 Tbit/s (10 x 100 Gbit/s) unrepeatered transmission over 500.5 km using dual polarization quadrature phase shift keyed (DP-QPSK) format and real-time processing. Such ultra-long distance is enabled by the use of high-performance 100G DP-QPSK transponders (the required optical signal-to-noise ratio is 12 dB), ultra-low loss Corning SMF-28 ULL fiber (the average attenuation of the spools used in this experiment <0.160 dB/km), and optimization of remotely-pumped optical amplifiers. To the best of our knowledge this is the longest unrepeatered 100G-based 1 Tb/s WDM transmission distance reported to date.
A novel distributed temperature variation sensor based on a phase-sensitive optical time-domain Rayleigh reflectometer is described and demonstrated experimentally. The measurement technique employs a standard single-mode fiber probe with dual pulses and allows precise tracking of the backscattered signal optical phase variation in time. The phase variation depends on the fiber temperature, with the experimentally measured calibration factor being consistent with that of the theoretical model. The demonstrated technique is capable of providing an operating range of ~50 km with a spatial resolution of ~15 m and offers a simple alternative to distributed temperature sensors based on Raman and Brillouin scattering.
Modulation instability (MI) in optical fibers adversely affects performance of phase-sensitive optical time domain reflectometers causing reduction of statistical visibility of the coherent reflectograms and corresponding degradation of the phase sensitive signal. This effect limits intensity of the probing pulse and imposes limits on the reflectometer operational range. Intensity limits imposed by the MI development were quantified for different positive dispersion fibers using nearly rectangular ~200 ns pulses at 1.5 µm wavelengths. MI development and reversible character of energy exchange between narrowband probing pulse and wideband optical noise known as Fermi–Pasta–Ulam energy recursion were observed. It is demonstrated both experimentally and numerically that the operational range of coherent reflectometers can be extended by increasing probing pulse energy if negative (normal) dispersion fibers are used, where MI development is suppressed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.