OSA/ANIC/IPR/Sensors/SL/SOF/SPPCom/2011
AMD4.pdf
Optical Subsystems for Next Generation Access Networks (Invited) J. A. Lazaro1* OSA member, V. Polo1, B. Schrenk1, F. Bonada1, I. Cano1, E. T. Lopez1, C. Kazmierski2, G. de Valicourt2, R. Brenot2, J. Bauwelinck3, X.-Z. Qiu3, P. Ossieur4, M. Forzati5, P.-J. Rigole6, I. T. Monroy7, E. Tangdiongga8, M. Morant9, L. Nicolau10, A. L. Teixeira10, D. Erasme11, D. Klonidis12, I. Tomkos12 OSA member, J. Prat1 OSA member, C. Kouloumentas13, H. Avramopoulos13 1
Universitat Politècnica de Catalunya, Dept. TSC, Jordi Girona 1, 08034 Barcelona, Spain (Tel. +34-93-401-7179 / Fax 7200) Alcatel-Thales III-V labs, a joint Laboratory of "Alcatel Lucent Bell Labs" and "Thales Research & Technology" Campus Polytechnique, 1, Avenue A. Fresnel, 91767 Palaiseau cedex, France; 3INTEC/IMEC-Ghent University, Sint-Pietersnieuwstraat 41, B-9000 Gent, Belgium; 4 Tyndall National Institute & University College Cork, Ireland; 5Networking and Transmission Laboratory, Acreo AB, Kista S-164 40, Sweden; 6 IGNIS, Torshamnsgatan, 30A, Kista 164 40, Sweden; 7Danmarks Tekniske Universitet (DTU), Denmark; 8Technische Universiteit Eindhoven(TU/e), The Netherlands; 9Nanophotonics Technology Centre, Universidad Politécnica de Valencia, Spain; 10Institute of Telecommunications (IT), Portugal; 11 Institut Télécom, France; 12Athens Information Technology (AIT), Peania, Athens, Greece; 13School of Electrical & Computer Engineering, National Technical University of Athens, 9 Iroon Polytechniou, Zografou, 15773 Athens, Greece. *Corresponding author:
[email protected] 2
Abstract: 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 network; on the other hand, also opening fixed-mobile convergence solutions in next generation PON architectures. It is provided an overview of the optical subsystems developed for the implementation of the proposed NG-Access Networks. OCIS codes: (060.2330) Fiber optics communications; (060.2360) Fiber optics links and subsystems
1. Introduction Extending fiber reach to the final user has been always interesting for the telecommunication operators. Nevertheless, fiber deployment closer to the customer was not the best cost-effective option till 2005-2007 [1]. Since then, the progress in optical technologies, bringing down the component and system cost, coupled with broadbandwidth demands from triple-play and new services, have been motivating telecommunication companies and cable system operators to deploy a full set of Fiber-To-The-X architectures (FTTx) that commonly refers to FiberTo-The Node (FTTN), Fiber-To-The-Curb (FTTC), Fiber-To-The Business / Building (FTTB), and finally arriving to the customer: Fiber-To-The-Home (FTTH), and Fiber-To-The-Premises (FTTP) [2]. And during most recent years, fiber is been proposed for fiber in the home (FITH) access networks, by RoF techniques using POF or MMFs. Taking into account also energy consumption trends in Next Generation Access Networks (NG-AN), telecommunication companies are proposing FTTx architectures with minimized consumption minimization for a sustainable FTTx deployment [3], where, Passive Optical Networks (PON) and specially next generation PONs show a higher power efficiency [4]. Finally, latest vision papers and recently financed research projects are envisioning and investigating NG-AN providing a complete fixed-mobile convergence over a NG-PON architecture [5], by applying OFDM technology [6] or RoF techniques [7]. 2. Cost/energy-effective ONU sub-systems for higher data rates, higher-split PONs and new functionalities 0
Relative e/o response [dB]
User Terminal subsystems are key for the deployment of future access networks, as they have a significant impact on the CapEx, requiring -3 equalized simplicity and cost and energy efficiency for the ONU of the user 2.5 -6 terminal equipment. In order to fulfill this request, compact devices such unequalized 7.2 as combinations of SOA and EAM provide a promising solution for RSOA Input pow er: -9 -15 dBm integrated ONU, maintaining low cost and energy consumption, while -20 dBm providing the required higher data rates, in the range of 10 Gb/s and new -25 dBm -12 functionalities of future access networks. 0 2 4 6 8 Modulation frequency [GHz] The cost of the ONU, mainly the packaging cost, is significantly 1: Electro-optical response of the RSOA reduced by the introduction of reflective devices such as RSOA. Fig without (○) and with (●▲■) passive RC-equalizer. Nevertheless, the difficulties in achieving higher data rates than 2.5G/s with these kind of devices, together with the impairments arising in full-duplex transmission on a single wavelength are motivating an important research activity [8] and an important research topic in EURO-FOS project [9]. At this previous publication, it reported highlighted results developed in this project for: a) Achieving high data rate (10 Gb/s) transmission with low-bandwidth (1.2 GHz) RSOA transmitter by electronic equalization and chirp management [9]; b) Photonic integrated solutions for full-duplex transmission on a single wavelength based: b1) on
OSA/ANIC/IPR/Sensors/SL/SOF/SPPCom/2011
AMD4.pdf
Iref1
3. Optical Line Terminal (OLT) and Remote Node (RN) sub-systems for higher capacity & extended PONs
Iref2
Reflectors
orthogonal FSK/ASK transmission and FSK to ASK conversion in a SOA/REAM chip; b2) optical downstream cancelation by Fabry Pérot filter or ring resonator; c) Burst-mode transmitter for 10 Gb/s PONs [9]. Recently new highlight progresses have been achieved in the frame of this project. On the one hand, it has been demonstrated 10 Gb/s operation of a RSOA, Fig 1, with high optical power budgets of up to 28 dB, providing error free transmission, without error correcting codes or electronic equalizers, for input powers to the RSOA as low as −20 dBm. Furthermore, a vector modulator, providing QAM signals for upstream transmission has been experimentally demonstrated using and integrated SOA/REAM [10].
MMI coupler
I Optical Line Terminals are also critical subsystems, determining Phase significantly the performance and flexibility of the access network. Both Gain I OLT RX and TX are under intensive research. Regarding OLT-RX, the SOA I extension of hybrid DWDM/TDM at 10 Gb/s requiring development of PIN-based 10Gb/s BM-RX [11] and APD-based BM-RX for future 10 Gb/s Fig 2: MG-Y tunable laser and TX subsystem. symmetric G-PONs, operating without amplifiers [12]. Regarding the OLT-TX, tunable laser diodes are promising technology, providing flexibility to access- and optical burst switching networks. Among the available laser sources, the Modulated Grating Y structure (MG-Y) laser is a multi-electrode fast tunable device with accurate wavelength tunability and wide tuning range that can be obtained without gain section current adjustments [13]. Further it can be of interest as ONU BM-TX due to its potential low cost, as recently demonstrated experimentally in a ring+tree PON for 640 users [14]. ph
gain
soa
4. Extended PONs modulations formats, transmission and mitigation While currently under deployment PONs may offer access to 32 to 128 users in the range of 20 km, novel architectures and technologies focus on extending the number of users that can be reached > 1000 users and reach of the AN to about 100 km. In this direction, significant progress has been achieved. On one hand, providing service to > 4000 users in purely TDM-based PON by a novel pumping scheme that reuses the ASE from a SOA- or RSOAbased ONU [15], and also a 135 km and 8192-split DWDM-TDMA PON with 2x32x10 Gb/s capacity by 10 Gb/s REAM-SOA based ONUs and 3R 10Gb/s burst-mode RXs [16]. 5. Cost-effective, flexible hybrid wired/wireless converged solutions Finally, several activities are leading to the convergence of wired and wireless solution, e.g. demonstrating Bidirectional CWDM RoF transmission of triple-format full-standard OFDM signals in coexistence: UWB, WiMAX and LTE, leading to 1.178 Gbit/s full-duplex over 50.6 km SSMF [17]. Also 10 GHz Single Side Band RoF transmission over 150km of fiber has been demonstrated using an integrated EML [18]. Finally, the same low cost RSOA devices, proposed in section 2 for cost/energy-effective ONU sub-systems are also used for colorless remote modulator at the antenna unit, transmitting standard Wi-Fi signals, IEEE 802.11 g, with 64 QAM format [19]. Acknowledgement: This work was supported by EURO-FOS NoE.
6. References [1] T. S. El-Bawab, “FTTx: The Rise of Broadband Optical Access” Globecom Workshops, 26-30 Nov. Washington, DC, U.S.A., 2007. [2] A. M. J. Koonen, “Fiber to the home/fiber to the premises: what, where, and when?,” Proc. IEEE 94, 911, 2006. [3] C. Bianco et al., “Energy consumption trends in the next generation access network - a telco perspective”, INTELEC’07, 737, 2007. [4] A. Lovric et al, “Power Efficiency of SARDANA and Other Long-Reach Optical Access Networks”, ONDM’11, S5-2, 2011. [5] M. A. Ali et al, “On the Vision of Complete Fixed-Mobile Convergence”, JLT 28, 2343, 2010. [6] J. Prat et al, “New FTTH Architectures for NG-PON-2”, ANIC’10, ATuA4, 2010. [7] “Fibre Optic Networks for Distributed, Extendible Heterogeneous Radio Architectures and Service Provisioning” (FUTON) [8] A. Borghesani, “Reflective based active semiconductor components for next generation optical access networks”, ECOC’10, Mo.1.B.1, 2010. [9] B. Schrenk et al, “User-Terminal Subsystems of Next-Generation Access Networks: Trends and Challenges”, ANIC’10, AWA4, 2010. [10] B. Schrenk et al, “SOA/REAM as Vector Modulator for QAM Upstream”, OFC’11, OThK1, 2011. [11] P. Ossieur et al, “A symmetric 320Gb/s capable, 100km extended reach hybrid DWDM-TDMA PON”, OFC’10, NWB1, 2010. [12] X. Z. Qiu et al, ”Evolution of Burst Mode Receivers”, ECOC’09, We.7.5.1, 2009. [13] M. Mestre et al, “Tuning Characteristics and Switching Speed of a Modulated Grating Y Structure Laser for ...”, ANIC’10, AThC2, 2010. [14] F. Bonada et al, “All-Optical Intra-PON Data Routing Between ONUs with a MG-Y Tunable Laser as 2.5 Gbps...”, OFC’11, JWA074, 2011. [15] B. Schrenk et al, “Energy-Efficient Optical Access Networks Supported by a Noise-Powered Extender Box”, JSTQE, to be published, 2011. [16] P. Ossieur et al, “A 135-km 8192-Split Carrier Distributed DWDM-TDMA PON With 2 32 10 Gb/s Capacity”, JLT 29, 463, 2011 [17] M. Morant et al, “Full Standard Triple-Play Bi-Directional and Full-Duplex CWDM Transmission in PON”, OFC’11, OWB3, 2011 [18] M. Petit, et al, “Dual-modulation of a novel Electro-absorption Modulated Laser for Radio-over-Fiber Systems”, Photonics Europe’10, 2010. [19] G de Valicourt et al, “Radio-Over-Fiber Access Network Architecture Based on New Optimized RSOA Devices ...”, TMTT 58, 3248, 2010
