1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T Series G TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Supplement 64 (02/2018) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS PON transmission technologies above 10 Gbit/s per wavelength ITU-T G-se
2、ries Recommendations Supplement 64 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS
3、 OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION M
4、EDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.
5、6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. G series Supplement 64 (02/2018) i Supplement 64 to ITU-T G-series Recommendations PON transmiss
6、ion technologies above 10 Gbit/s per wavelength Summary Supplement 64 to ITU-T G-series Recommendations describes characteristics of optical transmission above 10 Gbit/s per wavelength between the optical line termination (OLT) and the optical network unit (ONU). It reviews challenges of transmissio
7、n above 10 Gbit/s in optical access. A set of assumed system requirements is developed as a basis for the discussion of candidate technologies. Some aspects considered include signal modulation selection, optical transmitter design, optical receiver design, and wavelength dependency. Coexistence wit
8、h other optical access systems is also investigated as a key factor of wavelength planning. The line rate per wavelength in the existing PON systems, such as GPON, XG(S)-PON, TWDM-PON, is up to 10 Gbit/s. For High-speed PON, line rate per wavelength will exceed 10 Gbit/s, in order to provide higher
9、bandwidth capability for growing services requirement. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G Suppl. 64 2018-02-09 15 11.1002/1000/13589 Keywords High-speed PON, modulation technologies. * To access the Recommendation, type the URL http:/handle.itu.int/ in the add
10、ress field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii G series Supplement 64 (02/2018) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications
11、, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications o
12、n a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid d
13、own in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this publication, the expression “Administration“ is used for conciseness to indicate both a telecommunication a
14、dministration and a recognized operating agency. Compliance with this publication is voluntary. However, the publication may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the publication is achieved when all of these mandatory provision
15、s are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the publication is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the po
16、ssibility that the practice or implementation of this publication may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the p
17、ublication development process. As of the date of approval of this publication, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this publication. However, implementers are cautioned that this may not represent the latest information and
18、are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2018 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. G series Supplement 64 (02/2018) iii Table of Contents P
19、age 1 Scope . 1 2 References . 1 3 Definitions 2 3.1 Terms defined elsewhere 2 3.2 Terms defined in this Supplement 5 4 Abbreviations and acronyms 5 5 Conventions 7 6 System architectures . 7 7 Requirements 8 7.1 Physical layer requirements 8 7.2 Service requirements 9 7.3 System level requirements
20、9 7.4 Operational requirements . 10 7.5 Coexistence and migration . 10 8 Candidate technologies above 10 Gbit/s per wavelength . 10 8.1 Modulation technologies 10 8.2 Transmitter and receiver technologies 35 8.3 Optical amplifier technologies . 38 8.4 Wavelength allocation options . 41 8.5 Alternati
21、ve wavelength options for future 25G and 50G PON 41 8.6 Forward error correction options for high-speed PON . 41 Bibliography. 44 G series Supplement 64 (02/2018) 1 Supplement 64 to ITU-T G-series Recommendations PON transmission technologies above 10 Gbit/s per wavelength 1 Scope This Supplement de
22、scribes the characteristics of optical transmission above 10 Gbit/s per wavelength between the optical line termination (OLT) and the optical network unit (ONU). It reviews challenges of transmission above 10 Gbit/s in optical access. A set of assumed system requirements is developed as a basis for
23、the discussion of candidate technologies. Some aspects considered include signal modulation selection, optical transmitter design, optical receiver design, and wavelength dependency. Coexistence with other optical access systems is also investigated as a key factor of wavelength planning. 2 Referenc
24、es ITU-T G.652 Recommendation ITU-T G.652 (2016), Characteristics of a single-mode optical fibre and cable. ITU-T G.657 Recommendation ITU-T G.657 (2016), Characteristics of a bending-loss insensitive single-mode optical fibre and cable. ITU-T G.902 Recommendation ITU-T G.902 (1995), Framework Recom
25、mendation on functional access networks (AN) Architecture and functions, access types, management and service node aspects. ITU-T G.989 Recommendation ITU-T G.989 (2015), 40-Gigabit-capable passive optical networks (NG-PON2): Definitions, abbreviations and acronyms. ITU-T G.9807.1 Recommendation ITU
26、-T G.9807.1 (2016), 10-Gigabit-capable symmetric passive optical network (XGS-PON). Agrawal-1 Agrawal, G., Anthony, P., Shen, T. (1988), Dispersion penalty for 1.3-m Lightwave systems with multimode semiconductor lasers, J. Lightwave Technology, volume 6, number 5. Agrawal-2 Agrawal, G.P. and Dutta
27、N.K. (1986), Long-Wavelength Semiconductor Lasers. New York: Van Nostrand Reinhold. Beijing Univ Fiber communication system, Beijing University of posts and telecommunications publishing Group, p. 183. Ghelfi Ghelfi, P., Bogoni, A., and Poti, L. (2003), Numerical model of the dynamic absorption vari
28、ation in QW-EAM for ultrafast all-optical signal IEEE Proc.-Circuits Devices Syst., vol. 150, pp. 512-515. Houtsma Houtsma, V., van Veen, D. and Harstead, E. (2016), Unified Evolution-Ready 25/50/100 Gbps-EPON Architecture Proposal, IEEE 802.3ca Task Force, May. Kazovsky L. Kazovsky et al. (2011), B
29、roadband Optical Access Networks, John Wiley 42nd European Conference on Optical Communication. van Veen van Veen, D., Houtsma, V. (JLT vol.34 n.4), A Study of Options for High-Speed TDM-PON Beyond 10G. Winzer Winzer, P., Essiambre, R., Advanced modulation formats for high-capacity optical transport
30、 networks J. Journal of Lightwave Technology, 2006, 24: 4711-4728. Yamamoto Yamamoto, T. (2012), High-speed directly modulated lasers, Optical Fiber Communication Conference (OFC/NFOEC), March. Yao Yao, S., Liu, X. and Liu, D. (2016), The Impact of Differential Pre-coding on 25-Gbit/s EDB, NRZ, and
31、NRZ-NFC, IEEE 802.3ca Task Force, July. Yin X. Yin, J. Verbist, T. De Keulenaer, B. Moeneclaey, J. Verbrugghe, X. Qiu and J. Bauwelinck (2015), 25Gbit/s 3-level Burst-Mode Receiver for High Serial Rate TDM-PONs, Optical Fiber Communication Conference(OFC/NFOEC), March. 3 Definitions 3.1 Terms define
32、d elsewhere This Supplement uses the following terms defined elsewhere: 3.1.1 access network (AN) ITU-T G.902: An implementation comprising those entities (such as cable plant, transmission facilities, etc.) which provide the required transport bearer capabilities for the provision of telecommunicat
33、ions services between a service node interface (SNI) and each of the associated user-network interfaces (UNIs). 3.1.2 coexistence element ITU-T G.9807.1: A bidirectional functional element used to connect PON systems defined in different Recommendation series to the same ODN. 3.1.3 gigabit-capable p
34、assive optical network (G-PON) ITU-T G.989: A PON system supporting transmission rates in excess of 1.0 Gbit/s in at least one direction, and which implements the suite of protocols specified in the ITU-T G.984-series of Recommendations. 3.1.4 next generation PON (NG-PON) ITU-T G.989: In the context
35、 of ITU-T standards development activity, a generic term referencing the PON system evolution beyond G-PON. The G series Supplement 64 (02/2018) 3 concept of NG-PON currently includes NG-PON1, where the ODN is maintained from B-PON and G-PON, and NG-PON2, where a redefinition of the ODN is allowed f
36、rom that defined in B-PON and G-PON. 3.1.5 optical access network (OAN) ITU-T G.989: A part of an access network whose network elements are interconnected by optical communication channels. Note that an OAN may or may not extend all the way to the UNI, so that the user-side interface of the OAN does
37、 not necessarily coincide with the UNIs of the AN. 3.1.6 optical distribution network (ODN) ITU-T G.989: A point-to-multipoint optical fibre infrastructure. A simple ODN is entirely passive and is represented by a single-rooted point-to-multipoint tree of optical fibres with splitters, combiners, fi
38、lters and possibly other passive optical components. A composite ODN consists of two or more passive segments interconnected by active devices, each of the segments being either an optical trunk line segment or an optical distribution segment. A passive optical distribution segment is a simple ODN i
39、tself. Two ODNs with distinct roots can share a common subtree. 3.1.7 optical line termination (OLT) ITU-T G.989: A network element in an ODN-based optical access network that terminates the root of at least one ODN and provides an OAN SNI. 3.1.8 optical network terminal (ONT) ITU-T G.989: An ONU su
40、pporting a single subscriber. 3.1.9 optical network unit (ONU) ITU-T G.989: A network element in an ODN-based optical access network that terminates a leaf of the ODN and provides an OAN UNI. 3.1.10 passive optical network (PON) system ITU-T G.989: A combination of network elements in an ODN-based o
41、ptical access network that includes an OLT and one or more ONUs and implements a particular coordinated suite of physical medium dependent layer, transmission convergence layer and management protocols. 3.1.11 TWDM channel ITU-T G.989: In an NG-PON2 system, TWDM channel refers to the pair of one dow
42、nstream wavelength channel and one upstream wavelength channel providing point-to-multipoint connectivity by using, respectively, time division multiplexing and multiple access mechanisms. 3.1.12 TWDM PON ITU-T G.989: A multiple wavelength PON system in which each wavelength channel may be shared am
43、ong multiple ONUs by employing time division multiplexing and multiple access mechanisms. 3.1.13 wavelength channel ITU-T G.989: A unidirectional (downstream or upstream) optical communications channel characterized by a single unique central frequency or a set of unique central frequencies mapped t
44、o one WM tributary port. 3.1.14 wavelength multiplexer (WM) ITU-T G.989: A bidirectional functional element used to multiplex/ demultiplex between NG-PON2 wavelength channel pairs and channel groups. 3.1.15 10-gigabit-capable passive optical network (XG-PON) ITU-T G.9807.1: A PON system supporting n
45、ominal transmission rates on the order of 10 Gbit/s in at least one direction, and implementing the suite of protocols specified in the ITU-T G.987-series of Recommendations. XG-PON is the realization of NG-PON1. 3.1.16 XGS-PON ITU-T G.9807.1: A PON system that operates at a nominal line rate of 10
46、Gbit/s downstream and upstream. 3.1.17 dispersion ITU-T G.989: A physical phenomenon comprising the dependence of the phase or group velocity of a light wave in the medium, on its propagation characteristics such as optical frequency (wavelength) or polarization mode. 3.1.18 dynamic range ITU-T G.98
47、9: An optical receiver characteristic that is equal to the ratio of the receiver overload to the receiver sensitivity. 4 G series Supplement 64 (02/2018) 3.1.19 extinction ratio (ER) ITU-T G.989: With respect to a digital On-Off keying signal generated by an optical transmitter, the ratio of the ave
48、rage optical power level at the centre of the binary digit corresponding to the high intensity of light to the average optical power level at the centre of a binary digit corresponding to the low intensity of light. For the burst-mode signal, averaging is performed over the time periods when the tra
49、nsmitter is enabled, but excluding the associated transient times (see clause 5.13 of ITU-T G.989). For the continuous mode signal, averaging is performed over the entire signal string. 3.1.20 fibre distance ITU-T G.9807.1: The overall length of fibre (and, if applicable, equivalent fibre runs representing delay-inducing components) between the R/S and S/R-CG reference points. 3.1.21 line code ITU-T G.9807.1: In the NG-PON2 context, a code which transf
