TRECG975102IMSWE.docx

1、TRECG975102IMSWEINTERNATIONAL TELECOMMUNICATION UNIONITU-TG.975.1TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU(02/2004) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKSDigital sections and digital line system Optical fibre submarine cable systemsForward error correction for hig

2、h bit-rate DWDM submarine systemsITUT Recommendation G.975.1ITU-T G-SERIES RECOMMENDATIONSTRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKSINTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITSG.100G.199GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMSG.200G.299INDIVID

3、UAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINESG.300G.399GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINESG.400G.449COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONYG.450G.499T

4、ESTING EQUIPMENTSG.500G.599TRANSMISSION MEDIA CHARACTERISTICSG.600G.699DIGITAL TERMINAL EQUIPMENTSG.700G.799DIGITAL NETWORKSG.800G.899DIGITAL SECTIONS AND DIGITAL LINE SYSTEMG.900G.999GeneralG.900G.909Parameters for optical fibre cable systemsG.910G.919Digital sections at hierarchical bit rates base

5、d on a bit rate of 2048 kbit/sG.920G.929Digital line transmission systems on cable at non-hierarchical bit ratesG.930G.939Digital line systems provided by FDM transmission bearersG.940G.949Digital line systemsG.950G.959Digital section and digital transmission systems for customer access to ISDNG.960

6、G.969Optical fibre submarine cable systemsG.970G.979Optical line systems for local and access networksG.980G.989Access networksG.990G.999QUALITY OF SERVICE AND PERFORMANCE - GENERIC AND USER-RELATED ASPECTSG.1000G.1999TRANSMISSION MEDIA CHARACTERISTICSG.6000G.6999DIGITAL TERMINAL EQUIPMENTSG.7000G.7

7、999DIGITAL NETWORKSG.8000G.8999For further details, please refer to the list of ITU-T Recommendations.ITU-T Recommendation G.975.1Forward error correction for high bit-rate DWDMsubmarine systemsSummaryThis Recommendation describes the Forward Error Correction (FEC) functions that have highercorrecti

8、on ability than RS(255,239) code defined in ITU-T Rec. G.975 for the high bit-rate DWDM submarine cable systems. In Appendix I, super FEC schemes, which have higher-correction ability than RS(255,239) code, are also described. The use of this super FEC function in submarine terminal transmission equ

9、ipments (TTEs) should not be considered as mandatory. SourceITUT Recommendation G.975.1 was approved on 22February2004 by ITUT Study Group15 (20012004) under the ITUT RecommendationA.8 procedure.FOREWORDThe International Telecommunication Union (ITU) is the United Nations specialized agency in the f

10、ield of telecommunications. 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 on a worldwide basis.The W

11、orld Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITUT study groups which, in turn, produce Recommendations on these topics.The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution1.In s

12、ome areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC.NOTEIn this Recommendation, the expression Administration is used for conciseness to indicate both a telecommunication administration and a recognized

13、operating agency.Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure e.g. interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words shal

14、l 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 Recommendation is required of any party.INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice

15、 or implementation of this Recommendation 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 Recommendation developmen

16、t process.As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore st

17、rongly urged to consult the TSB patent database. ITU 2005All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU.CONTENTS Page1 Scope 12 References 13 Terms and definitions 23.1 Terms defined in other Recommendations 23

18、.2 Definitions 24 Abbreviations 35 Super FEC features 35.1 General principles of super FEC function 35.2 Super FEC scheme 46 Definition of super FEC function 46.1 Definition 46.2 Super FEC code algorithm 56.3 Properties for super FEC code 56.4 Super FEC frame structure 57 Parameters for super FEC 57

19、.1 Correction ability 57.2 Redundancy ratio 77.3 Latency 78 Supervision 78.1 Signal quality supervision 78.2 Connectivity supervision 7Appendix I Super FEC schemes 7I.1 Overview 7I.2 RS(255,239)/CSOC (n0/k0 = 7/6, J = 8) super FEC code 8I.3 Concatenated BCH super FEC codes 13I.4 RS(1023,1007)/BCH(20

20、47,1952) super FEC code 19I.5 Concatenated RS and product code super-FEC scheme 22I.6 LDPC super FEC code 24I.7 Two orthogonally concatenated BCH super FEC code 28I.8 Reed-Solomon (2720,2550) super FEC code 41I.9 Two interleaved extended BCH(1020,988) super FEC code 45ITU-T Recommendation G.975.1For

21、ward error correction for high bit-rate DWDMsubmarine systems1 ScopeThis Recommendation describes the Forward Error Correction (FEC) functions that have highercorrection ability than RS(255,239) code defined in ITU-T Rec. G.975 in the optical fibre submarine cable systems. This Recommendation also d

22、escribes the system requirement concerning supervision for the submarine cable systems. The applications being addressed in this Recommendation are both optically amplified repeatered systems (ITU-T Rec. G.977) and repeaterless optical systems (ITU-T Rec. G.973). The use of this FEC function in subm

23、arine terminal transmission equipments (TTEs) should not be considered as mandatory.It is not the intention of this Recommendation to pursue the transverse compatibility of the system. Therefore, the selection of the FEC frame structures described in this Recommendation is a matter of joint engineer

24、ing.The transmission signal under consideration could be STM-16, STM-64, STM-256, ODU1, ODU2, and ODU3, because submarine systems could be considered as one of the IaDI applications defined in ITU-T Rec. G.872. This does not mean that the bit rate is restricted within the above-mentioned signals.2 R

25、eferencesThe following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; u

26、sers of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recomm

27、endation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T Recommendation G.691 (2003), Optical interfaces for single-channel STM-64 and other SDH systems with optical amplifiers. ITU-T Recommendation G.693 (2003), Optical interfaces for intra-office systems. ITU-T R

28、ecommendation G.707/Y.1322 (2003), Network node interface for the synchronous digital hierarchy (SDH). ITU-T Recommendation G.709/Y.1331 (2003), Interfaces for the Optical Transport Network(OTN). ITU-T Recommendation G.798 (2002), Characteristics of optical transport network hierarchy equipment func

29、tional blocks. ITU-T Recommendation G.805 (2000), Generic functional architecture of transport networks. ITU-T Recommendation G.872 (2001), Architecture of optical transport networks. ITU-T Recommendation G.957 (1999), Optical interfaces for equipments and systems relating to the synchronous digital

30、 hierarchy. ITU-T Recommendation G.959.1 (2003), Optical transport network physical layer interfaces. ITU-T Recommendation G.972 (2000), Definition of terms relevant to optical fibre submarine cable systems. ITU-T Recommendation G.973 (2003), Characteristics of repeaterless optical fibre submarine c

31、able systems. ITU-T Recommendation G.975 (2000), Forward error correction for submarine systems. ITU-T Recommendation G.977 (2000), Characteristics of optically amplified optical fibre submarine cable systems. IEEE Standard 802.3-2002, Information Technology Telecommunication and Information Exchange between Systems LAN/MAN Specific Requirements Part 3: Carrier sense multiple access with collision detection (CSMA/CD) access method and physical layer specifications.3 Terms and definitions3.1 Terms defined in other Recommendations This Recommen