Keynote Speakers






Topic: Free Space Optical Systems Using All-Optical Relaying Schemes

Abstract:

The rapid increase in the number of internet and mobile users and high data-rate demanding applications has necessitated the quest for alternative wireless technologies in order to circumvent the spectrum congestion problem experience in radio frequency based system. Free space optical (FSO) communications is one of the proposed viable solutions,which offers extremely high bandwidth,interference and license free,highly directional and narrow beam,and inherently security. However,one of the major drawbacks of this technology is its vulnerability to the atmospheric phenomena such as fog,rain,smoke,and turbulence. Within this context,relay-assisted FSO systems have received attention in order to extend the link span,and improve the link performance and availability under the influence of  turbulence,since they take advantage of independent underlying fading paths,hence benefiting from spatial diversity.

The talk will introduce performance analyses for amplify-and-forward (AF) and decode-and-forward (DF) parallel or serial relay-assisted FSO links. We will illustrate that relay-assisted transmission allows a significant improvement of BER in the turbulence and in the power margin by more than 20 dB when using one and two (serial) relays between the source and destination. The demonstration will be given based on our experiments where we investigated the performance of a dual-hop 10 Gbps FSO with turbulence using all-optical switching in the relay terminal. We as well compared the BER performance of a triple-hop AF relaying FSO link with both direct and dual-hop links. And extension was done by considering each hop experiencing different turbulence regimes. Finally we will provide our recent results from 100 Gbps DF relay assisted FSO system using 2R all-optical regenerator.
Along with the main topic,the presentation will provide overview of research topics solved by Wireless and fiber optics team (optics.elmag.org) from the Czech Technical University in Prague led by prof. Stanislav Zvanovec,like Visible Light Communications (VLC) and Radio over FSO and fiber infrastructures.

Prof. Stanislav Zvanovec received his M.Sc. and Ph.D. degrees from the Faculty of Electrical Engineering,Czech Technical University (CTU) in Prague in 2002 and 2006,respectively. To date,he works as a full professor and deputy head of the Department of Electromagnetic Field and chairperson of PhD branch at CTU. His current research interests include Free Space Optical and fiber optical systems,Visible Light Communications,OLED,RF over optics and electromagnetic wave propagation issues for millimeter wave band. He is the head of Free-space and fiber optics group at CTU (optics.elmag.org). Till 2014 he was a chair of the Joint MTT/AP/ED/EMC chapter of the IEEE Czechoslovakia Section and he is head of the Commission F „Wave Propagation and Remote Sensing“ of the Czech National URSI Committee. He leads research and participates within in the frame of international projects ESA PECS no. 98069,ESA 4000105298/12/NL/CLP,ACE 2,EU COST projects IC1101 OPTICWISE (Optical Wireless Communications - An Emerging Technology) as vice chair of WG1,IC0802,IC0603,CA16220,Centre for quasi-optical.

Affiliation: Czech Technical University in Prague

Email : xzvanove@fel.cvut.cz




 

Topic: Optical Wireless Technology Promising Very High Data-Rate Underwater Communication Links

Abstract:

Today we are witnessing a growing need to high-rate data transmission in underwater missions in a wide range of application areas. In particular,with the increasing use of robotics in underwater missions and the recent advances in the design and development of autonomous underwater vehicles,there is an urgent need for broadband underwater links.  Recently,visible light communications (VLC) have received particular attention within this context due to their potential in providing very high-rate data transmission. In the challenging underwater environment,the major impairments of the communication link include high beam attenuation,especially in relatively high turbidity waters,and link misalignments. This talk provides an overview on underwater VLC systems and reviews the main considerations on the impact of the underwater channel and the transmission schemes. A few future research directions for improving the performance and the reliability of these links will be presented as well.

 

Dr. Mohammad-Ali Khalighi is Associate Professor in Ecole Centrale Marseille and head of “Telecommunications and Antenna Processing” in Fresnel Institute research lab. His main research areas of interest include signal processing for wireless communication systems with an emphasis on the physical layer aspects of free-space,underwater,and indoor visible-light optical communications. So far he has served as the Technical Program Committee member for more than 20 international conferences and workshops in the communications area and is currently serving as Associate Editor for IEEE Transactions on Communications. Also,he was the Vice Chair of WG2 of the FP7 IC1101 COST Action on optical wireless communications and is the project coordinator for the H2020 ITN MSCA “VISION” on visible-light communications. Dr. Khalighi is the recipient of the Scientific Excellence Award from the French Ministry of Research and Higher Education for the period of 2009–2017.

Affiliation: Fresnel Institute,Marseille,France

Email: Ali.Khalighi@fresnel.fr