Performance comparison of 40 Gb/s ULH transmissions using CSRZ-ASK or CSRZ-DPSK modulation formats on Ultra Wave™ fiber

In this work we present extensive comparisons between numerical modelling and experimental measurements of the transmission performance of either CSRZ-ASK or CSRZ-DPSK modulation formats for 40-Gb/s WDM ULH systems on UltraWave™ fiber spans with all-Raman amplification. We numerically optimised the amplification and the signal format parameters for both CSRZ-DPSK and CSRZ-ASK formats. Numerical and experimental results show that, in a properly optimized transmission link, the DPSK format permits to double the transmission distance (for a given BER level) with respect to the ASK format, while keeping a substantial OSNR margin (on ASK modulation) after the propagation in the fiber line. Our comparison between numerical and experimental results permits to identify what is the most suitable BER estimator in assessing the transmission performance when using the DPSK format. © 2007 Optical Society of America

Multi-band optical systems to enable ultra-high speed transmissions

Current forecasts indicate that the fastest growing IP-traffic is in metro and data center interconnect (DCI) [1]. The exploitation of the entire low-loss spectrum of single-mode fibers (SMF) (from 1260 nm up to 1620 nm) was proposed to avoid the predictable capacity crunch and the eventual need for a new fibre infrastructure roll-out. First analytic result considering multi-band (MB) transmission (from O- to L-band) hint an achievable traffic load exceeding 200 Tb/s for a 500 km link in a single SMF [2]

Upgrade capacity scenarios enabled by multi-band optical systems

The ITU-G.652D is the most deployed optical fiber worldwide and presents a wide low-loss window with negligible water absorption peak. Multi-band systems exploit this characteristic to increase the transmission capacity. In this work, we show the optical degradation in terms of generalized signal-to-noise ratio, on different bands, resulting from successive channel upgrades until the complete low-loss window is occupied

Coupled Dipole Method Determination of the Electromagnetic Force on a Particle over a Flat Dielectric Substrate

We present a theory to compute the force due to light upon a particle on a dielectric plane by the Coupled Dipole Method (CDM). We show that, with this procedure, two equivalent ways of analysis are possible, both based on Maxwell's stress tensor. The interest in using this method is that the nature and size or shape of the object, can be arbitrary. Even more, the presence of a substrate can be incorporated. To validate our theory, we present an analytical expression of the force due to the light acting on a particle either in presence, or not, of a surface. The plane wave illuminating the sphere can be either propagating or evanescent. Both two and three dimensional calculations are studied.Comment: 10 pages, 8 figures and 3 table

Enabling transparent technologies for the development of highly granular flexible optical cross-connects

Flexible optical networking is identified today as the solution that offers smooth system upgradability towards Tb/s capacities and optimized use of network resources. However, in order to fully exploit the potentials of flexible spectrum allocation and networking, the development of a flexible switching node is required capable to adaptively add, drop and switch tributaries with variable bandwidth characteristics from/to ultra-high capacity wavelength channels at the lowest switching granularity. This paper presents the main concept and technology solutions envisioned by the EU funded project FOX-C, which targets the design, development and evaluation of the first functional system prototype of flexible add-drop and switching cross-connects. The key developments enable ultra-fine switching granularity at the optical subcarrier level, providing end-to-end routing of any tributary channel with flexible bandwidth down to 10Gb/s (or even lower) carried over wavelength superchannels, each with an aggregated capacity beyond 1Tb/s. © 2014 IEEE