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Thursday 28th of november 2019, 2:00 pm, at Nokia Bell-Labs, Nozay, France

Kaoutar BENYAHYA defends his PhD thesis

« Mode-Group Division Multiplexing for Short Reach Optical Communications »

Optical communications ; space multiplexing ; mode multiplexing ; data center interconnects


The ever-growing demand of data traffic will be fueled by revolutionary technologies such as virtual reality (VR), augmented reality (AR) and Internet of things (IoT). Therefore, optical networks should support the requirements of these services in terms of high capacity, low latency and high reliability. In fact, large scale capacity is a critical need for fiber optic communication systems deployed in local area networks as well as in datacenters. For both applications, systems relying on IMDD are highly demanded due to their low cost and compatibility with short range applications.

In this thesis, we address the need of increasing the data rates for short reach optical communication systems based on mode group division multiplexing and direct detection schemes. Firstly, we focus on increasing the capacity of already deployed standard multimode fibers in local area networks and intra-datacenters communication where the distance is shorter than 5 km. Secondly, we extend our solution to longer reach applications such as inter-datacenter interconnects. In both cases, optical link architectures, including transmitters, receivers and the optical fibers are analyzed. Moreover, modulation formats adapted to IMDD systems such as single carrier 4-PAM and multicarrier DMT are compared in the context of space division multiplexing transmission.

In this work we demonstrated the achievable benefit of mode group multiplexing combined with IMDD schemes. First, 5 Tb/s has been achieved over 2.2 km of conventional multimode fiber (OM2). Secondly, transmission record at the time of its realization of 14.5 Tb/s over OM2 fiber has been demonstrated. Finally, 200 Gb/s over 20 km of FMF) a été démontré, ce qui étend les avantages du multiplexage par groupes de modes aux applications à longue distance par rapport aux réseaux <acronym has been achieved, which extends the benefit of mode group multiplexing to longer reach applications compared to LAN and intra-datacenter where the maximum distance is limited to 5 km.


Committee members
Sophie LAROCHELLE Professor, COPL, Université Laval, QuébecExaminator
Yves JAOUEN Professor, Télécom Paris, PalaiseauExaminator
Christelle AUPETIT-BERTHELEMOT Professor, Xlim, Université de LimogesMember
Nicolas DUBREUIL Professor, IOGS, TalenceMember
Marianne BIGOT-ASTRUC PhD, Prysmian Group, FranceMember
Christian SIMONNEAU PhD, Alcatel-Submarine Networks, Nozay PhD Manager
Amirhossein GHAZISAEIDI PhD, Nokia Bell-Labs, Nozay PhD Manager
Christophe PEUCHERET Professor, Institut Foton, Université de Rennes 1PhD Supervisor