Louis-Anne de Montmorillon

Micro-bend losses of trench-assisted single-mode fibers

We study, both theoretically and experimentally, the micro-bending behavior of single-trench-assisted bend-insensitive and large effective-area fibers. We show how the trench significantly reduces the micro-bend losses compared to those of standard step-index profiles of single-mode fibers.

Next Generation SMF with reduced bend sensitivity for FTTH Networks

A new trench-assisted generation of single-mode fiber offers strongly reduced bending sensitivity. We report the lowest bending loss for a fiber still compliant with G.652 ITU-T standard and with losses below 0.2dB/km over C+L wavelength bands.

Analytical solution of polarization mode dispersion for triangular spun fibers

An analytical solution for the differential group delay of a fiber spun according to a triangular function is derived from concatenation of Jones matrices for a fiber length equal to N x T, where T is the spinning period and N is an integer. This solution holds for any value of linear deterministic birefringence delta beta of amplitude A and period T of the triangular spinning function. We use the solution to emphasize the effect of birefringence on the efficiency of the spinning function.

Low-cost 100 Gbps transport solution based on DCO-CFP and G.657.A2 fibre for long-haul WDM transmission

We show here that combination of “low-cost” transport solutions based on 100 Gbps DCO-CFP interface and G.657.A2 fibre is able to address long-haul (~2000 km) WDM transmission applications. A performance comparison is carried out with “premium” solutions based on 100 Gbps coherent OIF-MSA transceivers and legacy G.652.D fibre.

Recent developments in bend-insensitive and ultra-bend-insensitive fibers

Designed to overcome the limitations in case of extreme bending conditions, Bend- and Ultra-Bend-Insensitive Fibers (BIFs and UBIFs) appear as ideal solutions for use in FTTH networks and in components, pigtails or patch-cords for ever demanding applications such as military or sensing. Recently, however, questions have been raised concerning the Multi-Path-Interference (MPI) levels in these fibers. Indeed, they are potentially subject to interferences between the fundamental mode and the higher-order mode that is also bend resistant. This MPI is generated because of discrete discontinuities such as staples, bends and splices/connections that occur on distance scales that become comparable to the laser coherent length. In this paper, we will demonstrate the high MPI tolerance of all-solid single-trench-assisted BIFs and UBIFs. We will present the first comprehensive study combining theoretical and experimental points of view to quantify the impact of fusion splices on coherent MPI. To be complete, results for mechanical splices will also be reported. Finally, we will show how the single-trench- assisted concept combined with the versatile PCVD process allows to tightly control the distributions of fibers characteristics. Such controls are needed to massively produce BIFs and to meet the more stringent specifications of the UBIFs.

Design and performances of trench-assisted G.657.A&B fiber optimized towards more space savings and miniaturization of components

After many years of expectations, Fiber To The Home (FTTH) has finally become a reality with a wide number of projects already running worldwide and growing. Optical fiber is inevitably taking more and more importance in our environment, but for many good reasons, the space we are truly willing or able to allocate to it remains limited. These installation constrainsts have turned into additional requirements that need to be addressed for both active and passive components. If exceptional bending performances obtained without degrading backward compatibilities is a pre-requisite to deployment success,1 other parameters also need to be carefully taken into account when designing the ideal candidate for use in confined environments. Among them, one can cite the bend loss homogeneity over length and bending directions, the resistance to high optical power under bending and the tolerance to modal noise. In this paper, we present the design and performances of a bend insensitive fiber optimized towards more space savings and miniaturization of components. In addition to exceptional bending performances - lower than 0.1 dB/turn over a 5 mm bending radius -, its design guarantees impressive homogeneity levels and enhanced safety margins for high power applications while being still resistant to modal noise. Successfull cleave- and splice-ability results are finally presented, making this fiber ideally suited for use in components, pigtails and patchcords.