Now showing items 21-40 of 41

  • High capacity optical networks based on space division multiplexing 

    Behnam Shariati, Mohammad; Comellas Colomé, Jaume; Klonidis, Dimitrios; Velasco Esteban, Luis Domingo; Tomkos, Ioannis (John Wiley & sons, 2017-09-01)
    Part of book or chapter of book
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    This book discusses Elastic Optical Networks (EONs) from an operational perspective. It presents algorithms that are suitable for real-time operation and includes experimental results to further demonstrate the feasibility ...
  • Hitless dynamic wavelength allocation in coherent WDM-PONs 

    Presi, Marco; Rannello, M.; Artiglia, Massimo; Tomkos, Ioannis; Cano Valadez, Iván Nicolás; Prat Gomà, Josep Joan; Ciaramella, Ernesto (2016)
    Conference lecture
    Restricted access - publisher's policy
    We introduce a novel algorithm for real-time ONU activation (¿ - assignment) and reconfiguration (¿ - tuning) in WDM coherent PONs. The algorithm prevents service interruption of lighted channels and it is experimentally ...
  • Hitless wavelength assignment in filterless optical access networks 

    Presi, Marco; Rannello, M.; Artiglia, Massimo; Tomkos, Ioannis; Cano Valadez, Iván Nicolás; Prat Gomà, Josep Joan; Ciaramella, Ernesto (Institute of Electrical and Electronics Engineers (IEEE), 2016)
    Conference report
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    Advantages offered by coherent detection systems in access networks are not limited to the increase of power budget due to the superior sensitivity. Channel selectivity is another intriguing feature offered by coherent systems ...
  • Impact of filter sharpness on the performance of elastic optical networks 

    Sayyad Kodashenas, Pouria; Rivas Moscoso, José Manuel; Klonidis, Dimitrios; Tomkos, Ioannis; Behnam Shariati, Mohammad; Comellas Colomé, Jaume (Institute of Electrical and Electronics Engineers (IEEE), 2015)
    Conference report
    Restricted access - publisher's policy
    Elastic optical network (EON) technology arises as a promising solution for future high-speed optical transport networks, inasmuch as it can provide superior flexibility and scalability in the spectrum allocation for ...
  • Impact of spatial and spectral granularity on the performance of SDM networks based on spatial superchannel switching 

    Behnam Shariati, Mohammad; Rivas Moscoso, José Manuel; Marom, Dan M.; Ben Ezra, Shalva; Klonidis, Dimitrios; Velasco Esteban, Luis Domingo; Tomkos, Ioannis (2017-07-01)
    Article
    Open Access
    Spatially integrated switching architectures have been recently investigated in an attempt to provide switching capability for networks based on spatial division multiplexing (SDM) fibers, as well as to reduce the ...
  • Investigation of mid-term network migration scenarios comparing multi-band and multifiber deployments 

    Shariati, Behnam; Sayyad Khodashenas, Pouria; Rivas Moscoso, José Manuel; Ben Ezra, Shalva; Klonidis, Dimitrios; Jiménez, Felipe; Velasco Esteban, Luis Domingo; Tomkos, Ioannis (Institute of Electrical and Electronics Engineers (IEEE), 2016)
    Conference report
    Restricted access - publisher's policy
    We compared two different mid-term migration scenarios for core network capacity scaling, realized using either multi-band or multi-fiber systems. We show, under realistic assumptions of current costs, that the multi-fiber ...
  • L-Band In-Line Remote Amplification for an Extended WDM/PON Ring Architecture 

    Chatzi, Sotiria; Tomkos, Ioannis; Lázaro Villa, José Antonio; Prat Gomà, Josep Joan (IEEE Press. Institute of Electrical and Electronics Engineers, 2009-06-28)
    Conference report
    Open Access
    In this paper, a study on a fully passive WDM/PON ring architecture which reaches 19 km distance, while serving more than 1000 users with symmetric several hundred Mbit/s per user is presented. The design is based on ...
  • On the benefits of FMF based data center interconnection utilizing MIMO-less PAM-M transceivers 

    Behnam Shariati, Mohammad; Diamantopoulos, Nikolaos-Panteleimon; Klonidis, Dimitrios; Comellas Colomé, Jaume; Tomkos, Ioannis (Institute of Electrical and Electronics Engineers (IEEE), 2017)
    Conference lecture
    Restricted access - publisher's policy
    Space division multiplexing (SDM) has been proposed to cost-effectively increase the capacity of optical transmission systems. The cost savings can be realized by introducing some levels of spatial integration of elements. ...
  • On the offline physical layer impairment aware RWA algorithms in transparent optical networks: state-of-the-art and beyond 

    Azodolmolky, Siamak; Pointurier, Yvan; Klinkowski, Miroslaw; Marín Tordera, Eva; Careglio, Davide; Solé Pareta, Josep; Angelou, Marianna; Tomkos, Ioannis (IEEE Press and Wiley, 2009-02-18)
    Conference report
    Open Access
    In transparent optical networks with no regeneration, the problem of capacity allocation to traffic demands is called "Roting and Wavelength Assignment". Much work on this topic recently has focused on the dynamic case, ...
  • Optical subsystems for next generation access networks 

    Lázaro Villa, José Antonio; Polo Querol, Víctor; Schrenk, Bernhard; Bonada Bo, Francesc; Cano Valadéz, Iván Nicolás; López Pastor, Eduardo Tommy; Kazmierski, Christophe; de Valicourt, Guilhem; Brenot, Romain; Bauwelinck, Johan; Xing-Zhi, Qiu; Ossieur, P.; Forzati, Marco; Rigole, Jean-Pierre; Monroy, I.T; Tangdiongga, E.; Morant, Maryland; Nicolau, L.; Teixeira, A.L.; Erasme, D.; Klonidis, Dimitrios; Tomkos, Ioannis; Prat Gomà, Josep Joan; Kouloumentas,, Christos; Avramopoulos, Hércules (2011)
    Conference report
    Restricted access - publisher's policy
    Recent optical technologies are providing higher flexibility to next generation access networks: on the one hand, providing progressive FTTx and specifically FTTH deployment, progressively shortening the copper access ...
  • Options for cost-effective capacity upgrades in backbone optical networks 

    Shariati, Behnam; Rivas Moscoso, José Manuel; Klonidis, Dimitrios; Tomkos, Ioannis; Ben Ezra, Shalva; Jiménez, Felipe; Marom, Dan M.; Sayyad Khodashenas, Pouria; Comellas Colomé, Jaume; Velasco Esteban, Luis Domingo (Institute of Electrical and Electronics Engineers (IEEE), 2016)
    Conference report
    Restricted access - publisher's policy
    Upgrading the capacity of backbone optical networks while delivering contents to the end-users with a reduced cost per bit is a day-by-day challenge of network operators. In this paper, we first discuss several mid-term ...
  • Performance issues in Optical Burst/Packet Switching 

    Klinkowski, Miroslaw; Careglio, Davide; Aracil Rico, Javier; Azodolmolky, Siamak; García Haro, Juan; Gunreben, Sebastian; Hu, Guoqiang; Izal, Mikel; Kimsas, Andreas; Veiga Gontán, Javier; Tzanakaki, Anna; Tomkos, Ioannis; Spadaro, Salvatore; Scharf, Joachim; Perelló Muntan, Jordi; Pavón Mariño, Pablo; Morató, Daniel; Magaña, Eduardo; Köhn, Martin (Springer, 2009-04-01)
    Part of book or chapter of book
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    This chapter summarises the activities on optical packet switching (OPS) and optical burst switching (OBS) carried out by the COST 291 partners in the last 4 years. It consists of an introduction, five sections with ...
  • Physical layer evaluation of OFDM-based access networks 

    Cano Valadéz, Iván Nicolás; Santos Blanco, M. Concepción; Prat Gomà, Josep Joan; Krimmel, H.G.; Kavatzikidis, T.; Giacoumidis, E.; Tomkos, Ioannis (IEEE Press. Institute of Electrical and Electronics Engineers, 2011)
    Conference report
    Restricted access - publisher's policy
    In this paper, we present a physical layer parameter optimization of direct-detection optical OFDM techniques at bitrates of 10 Gb/s and 40 Gb/s using an intensity modulation and two types of field modulation transmitte ...
  • Routing and wavelength assignment for transparent optical networks with QoT estimation inaccuracies 

    Azodolmolky, Siamak; Pointurier, Yvan; Angelou, Marianna; Solé Pareta, Josep; Tomkos, Ioannis (2010)
    Conference report
    Restricted access - publisher's policy
    We show how inaccuracies of Quality of Transmission (QoT) estimations, caused by imperfect models and lack of monitors in transparent optical networks, can be mitigated using a novel routing and wavelength assignment algorithm.
  • SARDANA: an all-optical access-metro WDM/TDM-PON 

    Spirou, S.; Tomkos, Ioannis; Prat Gomà, Josep Joan; Segarra Mullerat, Josep; Sales Zaragozá, Vicente; Lázaro Villa, José Antonio; Chanclou, Philippe; Soila, Risto; Teixeira, A.; Tosi Beleffi, Giorgio M. (2011)
    Conference report
    Open Access
    A new optical access network, named “Scalable Advanced Ring-based passive Dense Access Network Architecture” (SARDANA), is presented. It transparently integrates WDM metro and TDM PON access technologies, implementing ...
  • Simple intradyne PSK system for UDWDM-PON 

    Prat Gomà, Josep Joan; Polo Querol, Víctor; Zakynthinos, P.; Cano Valadéz, Iván Nicolás; Tabares, J.; Fàbrega Sánchez, Josep Maria; Klonidis, Dimitrios; Tomkos, Ioannis (2012-12-17)
    Article
    Open Access
    A homodyne coherent receiver for ultra-dense WDM-PON with off the shelf components is presented. It consists of a conventional DFB, phase switched clock signal, an optical coupler instead of a 90º hybrid, balanced ...
  • Spectrally and spatially flexible optical networks: recent developments and findings 

    Shariati, Mohammad Behnam; Klonidis, Dimitrios; Marom, Dan M.; Comellas Colomé, Jaume; Velasco Esteban, Luis Domingo; Tomkos, Ioannis (Institute of Electrical and Electronics Engineers (IEEE), 2018)
    Conference report
    Restricted access - publisher's policy
    Space division multiplexing (SDM) has been proposed as the ultimate solution to address the capacity crunch of optical transport networks. The efficient utilization of SDM requires some forms of spatial integration which ...
  • Techno-economics of resilient extended FTTH PONs 

    Prat Gomà, Josep Joan; Lázaro Villa, José Antonio; Chatzi, Sotiria; Tomkos, Ioannis (IEEE, 2011)
    Conference report
    Restricted access - publisher's policy
    This work analyses different architectures of protected FTTH passive optical networks in terms of device and infrastructure requirements and costs, considering different home density scenarios and volume projections. The ...
  • Technologies for cost-effective udWDM-PONs 

    Prat Gomà, Josep Joan; Cano Valadez, Iván Nicolás; Presi, Marco; Tomkos, Ioannis; Klonidis, Dimitrios; Vall-llosera, Gema; Brenot, Romain; Pous, R.; Papastergiou, george; Rafel, Albert; Ciaramella, Ernesto (2016-01-15)
    Article
    Open Access
    New technologies for ultradense WDM-PON (udWDM-PON), enabled by coherent techniques and low-cost devices, are developed for an efficient utilization of the optical spectrum, revealing that the “Wavelength-to-the-User” ...
  • Test-bed functionality of the SARDANA hybrid NG-PON 

    Prat Gomà, Josep Joan; Polo Querol, Víctor; Lázaro Villa, José Antonio; Bonada, F.; López Pastor, Eduardo Tommy; Schrenk, Bernhard; Omella, M.; Saliou, F.; Le, Q.T.; Chanclou, P.; Leino, D.; Soila, R.; Spirou, S.; Costa, L.; Teixeira, A.; Tosi-Beleffi, G.M.; Klonidis, Dimitrios; Tomkos, Ioannis (2011)
    Conference report
    Restricted access - publisher's policy
    The tests with broadband multimedia services of the SARDANA multi-layer prototype prove the feasibility of scalable hybrid DWDM/TDM-PON FTTH networks with resilient optically-integrated ring-trees architecture.