1、 International Telecommunication Union ITU-T G.976TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (05/2014) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital sections and digital line system Optical fibre submarine cable systems Test methods applicable to optical fibre s
2、ubmarine cable systems Recommendation ITU-T G.976 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
3、CHARACTERISTICS 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
4、 TRANSMISSION MEDIA 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 General G.900G.909 Parameters for optical fibre cable systems G.910G.919 Digital sections at hierarchical bit rate
5、s based on a bit rate of 2048 kbit/s G.920G.929 Digital line transmission systems on cable at non-hierarchical bit rates G.930G.939 Digital line systems provided by FDM transmission bearers G.940G.949 Digital line systems G.950G.959 Digital section and digital transmission systems for customer acces
6、s to ISDN G.960G.969 Optical fibre submarine cable systems G.970G.979Optical line systems for local and access networks G.980G.989 Metallic access networks G.990G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000
7、G.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. Rec. ITU-T G.976 (05/2014) i Recommendation ITU-T G.976 Test methods applicable to optical fibre sub
8、marine cable systems Summary It is to be recognized that numerous test methods are specific to particular optical fibre submarine cable system designs and are, therefore, proprietary information of the system designer/supplier. However, a common understanding needs to be met between the system desig
9、ner/supplier and the system purchaser/operator on the general purpose of testing and the meaning of the results. Recommendation ITU-T G.976 highlights the purpose of testing in optical fibre submarine cable systems and lists the main test methods applicable to these systems. Specific test methods ar
10、e described. This edition of the Recommendation includes the addition of test regarding vibration and shock resistance. History Edition Recommendation Approval Study Group Unique ID*1.0 ITU-T G.976 1997-04-08 15 11.1002/1000/4028 2.0 ITU-T G.976 2000-10-06 15 11.1002/1000/5189 3.0 ITU-T G.976 2004-0
11、6-13 15 11.1002/1000/7342 4.0 ITU-T G.976 2007-07-29 15 11.1002/1000/9160 5.0 ITU-T G.976 2010-07-29 15 11.1002/1000/10884 6.0 ITU-T G.976 2014-05-14 15 11.1002/1000/12182 _ *To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Re
12、commendations unique ID. For example, http:/handle.itu.int/11.1002/1000/ 11830-en. ii Rec. ITU-T G.976 (05/2014) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). Th
13、e 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 World Telecommunication Standa
14、rdization 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 down in WTSA Resolution 1. In some areas of information
15、technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Com
16、pliance 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 “shall“ or some other
17、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 RIGHTS ITU draws attention to the possibility that the practice or implemen
18、tation 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 development process. A
19、s 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, implementers are cautioned that this may not represent the latest information and are therefore strongly urge
20、d to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2014 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T G.976 (05/2014) iii Table of Contents Page 1 Scope 1 2 References. 1 3 D
21、efinitions 2 3.1 Terms defined elsewhere 2 3.2 Terms defined in this Recommendation . 2 4 Abbreviations and acronyms 3 5 Conventions 4 6 Purpose of testing in optical fibre submarine cable systems 4 6.1 Qualification tests . 4 6.2 Quality assurance tests . 5 6.3 Installation tests 6 6.4 Cable system
22、 commissioning tests . 8 6.5 Maintenance tests . 8 7 List of tests to be made on optical fibre submarine cable systems and applicable test methods 9 7.1 Tests on the optical fibres of the optical fibre submarine cable . 9 7.2 Tests on the optical fibre submarine cable . 12 7.3 Tests on optical fibre
23、 amplifiers of OSR 13 7.4 Tests on the terminal transmission equipment . 15 7.5 Tests on the power feeding equipment . 15 7.6 Tests on the link 15 7.7 Tests on the maintenance 16 8 Description of specific test methods applicable to optical fibre submarine cable systems 17 8.1 Tests on the optical fi
24、bres of the optical fibre submarine cable . 17 8.2 Tests on the optical fibre submarine cable . 18 8.3 Tests on optical fibre amplifiers of OSR 27 8.4 Tests on the terminal transmission equipment . 29 8.5 Tests on the power feeding equipment . 29 8.6 Tests on the link 29 8.7 Tests on the maintenance
25、 31 Annex A Definition of terms relevant to the tests on optical fibre submarine cables 34 A.1 Q factor . 34 Appendix I Detailed definitions relevant to optical fibre submarine cable systems . 35 I.1 Cable safety margin 35 I.2 Nominal permanent tensile strength (NPTS) . 35 I.3 Nominal operating tens
26、ile strength (NOTS) . 35 I.4 Nominal transient tensile strength (NTTS) 36 iv Rec. ITU-T G.976 (05/2014) Page Appendix II Test method for measuring Raman gain efficiency distribution 37 II.1 General . 37 II.2 Test apparatus . 37 II.3 Measurement procedure . 39 II.4 Presentation of the results . 39 Ap
27、pendix III Parameters for OTDR and COTDR 40 III.1 Table of parameters for OTDR and COTDR . 40 Bibliography. 41 Rec. ITU-T G.976 (05/2014) 1 Recommendation ITU-T G.976 Test methods applicable to optical fibre submarine cable systems 1 Scope Testing is of high importance for optical fibre submarine ca
28、ble systems since, together with a proper design and a careful definition of technologies, it is the only way to guarantee that the quality, lifetime and reliability performance of an optical fibre submarine cable system shall be met. It is to be recognized that numerous test methods are specific to
29、 particular system designs and are therefore proprietary information of the system designer/supplier. However, a common understanding needs to be met between the system designer/supplier and the system purchaser/operator on the general purpose of testing and the meaning of the results. Insofar as th
30、ey are applicable to optical fibre submarine cable systems, general test methods recommended by the ITU-T should be applied. It should be recognized that these methods may need adaptation to the specific characteristics of optical fibre submarine systems. It should also be recognized that some test
31、methods are specific to optical fibre submarine cable systems and are of little or no use elsewhere. The purpose of this Recommendation is to highlight the testing of optical fibre submarine cable systems by listing the main tests applicable to these systems and by describing test methods specific t
32、o these systems. 2 References The 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 s
33、ubject to revision; users 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 docume
34、nt within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T G.650.1 Recommendation ITU-T G.650.1 (2010), Definitions and test methods for linear, deterministic attributes of single-mode fibre and cable. ITU-T G.650.2 Recommendation ITU-T G.650.2 (
35、2007), Definitions and test methods for statistical and non-linear related attributes of single-mode fibre and cable. ITU-T G.661 Recommendation ITU-T G.661 (2007), Definitions and test methods for the relevant generic parameters of optical amplifier devices and subsystems. ITU-T G.671 Recommendatio
36、n ITU-T G.671 (2012), Transmission characteristics of optical components and subsystems. ITU-T G.702 Recommendation ITU-T G.702 (1988), Digital hierarchy bit rates. ITU-T G.780 Recommendation ITU-T G.780/Y.1351 (2010), Terms and definitions for synchronous digital hierarchy (SDH) networks. ITU-T G.7
37、83 Recommendation ITU-T G.783 (2006), Characteristics of synchronous digital hierarchy (SDH) equipment functional blocks. ITU-T G.810 Recommendation ITU-T G.810 (1996), Definitions and terminology for synchronization networks. 2 Rec. ITU-T G.976 (05/2014) ITU-T G.821 Recommendation ITU-T G.821 (2002
38、), Error performance of an international digital connection operating at a bit rate below the primary rate and forming part of an Integrated Services Digital Network. ITU-T G.823 Recommendation ITU-T G.823 (2000), The control of jitter and wander within digital networks which are based on the 2048 k
39、bit/s hierarchy. ITU-T G.826 Recommendation ITU-T G.826 (2002), End-to-end error performance parameters and objectives for international, constant bit-rate digital paths and connections. ITU-T G.828 Recommendation ITU-T G.828 (2000), Error performance parameters and objectives for international, con
40、stant bit-rate synchronous digital paths. ITU-T G.959.1 Recommendation ITU-T G.959.1 (2012), Optical transport network physical layer interfaces. ITU-T G.971 Recommendation ITU-T G.971 (2010), General features of optical fibre submarine cable systems. ITU-T G.972 Recommendation ITU-T G.972 (2011), D
41、efinition of terms relevant to optical fibre submarine cable systems. ITU-T G.973 Recommendation ITU-T G.973 (2010), Characteristics of repeaterless optical fibre submarine cable systems. ITU-T G.977 Recommendation ITU-T G.977 (2011), Characteristics of optically amplified optical fibre submarine ca
42、ble systems. ITU-T L.12 Recommendation ITU-T L.12 (2008), Optical fibre splices. IEC 61290 IEC 61290, Optical fibre amplifiers Test methods series. IEC/TR 62284 IEC/TR 62284 ed1.0 (2003), Effective area measurements of single-mode optical fibres Guidance. IEC/TR 62285 IEC/TR 62285 ed2.0 (2005), Appl
43、ication guide for non-linear coefficient measuring methods. IEC/TR 62324 IEC/TR 62324 ed2.0 (2007), Single-mode optical fibres Raman gain efficiency measurement using continuous wave method Guidance. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsew
44、here: 3.1.1 optical fibre amplifier (OFA) ITU-T G.661. 3.1.2 plesiochronous digital hierarchy (PDH) ITU-T G.702. 3.1.3 synchronous digital hierarchy (SDH) ITU-T G.780. Other terms used in this Recommendation are defined in ITU-T G.972. 3.2 Terms defined in this Recommendation None. Rec. ITU-T G.976
45、(05/2014) 3 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: APD Avalanche Photodiode ATM Alternative Test Method BBER Background Block Error Ratio BER Bit Error Ratio CBL Cable Breaking Load CF Compression Factor COTDR Coherent Optical Time Domain Refl
46、ectometry DC Direct Current DOHB Draw Off/Hold Back ESR Errored Second Ratio FA Fixed Analyser FWM Four-Wave Mixing GF Gain Flatness IOR Index Of Refraction LW Lightweight LWP Lightweight Protected MFD Mode Field Diameter NF Noise Figure NG Nominal Gain NOTS Nominal Operating Tensile Strength NPTS N
47、ominal Permanent Tensile Strength NSIP Nominal Signal Input Power NSOP Nominal Signal Output Power NTTS Nominal Transient Tensile Strength OA Optical Amplifier OFA Optical Fibre Amplifier O-E Opto-Electro OSR Optical Submarine Repeaters OTDR Optical Time Domain Reflectometry PDG Polarization Depende
48、nt Gain PDH Plesiochronous Digital Hierarchy PDL Polarization Dependent Loss PFE Power Feeding Equipment PHB Polarization Hole Burning PIN P Intrinsic N 4 Rec. ITU-T G.976 (05/2014) PMD Polarization Mode Dispersion RTM Reference Test Method SCI Self-Compensated Interferometric SDH Synchronous Digita
49、l Hierarchy SESR Severely Errored Second Ratio SNR Signal-to-Noise Ratio SOA Semiconductor Optical Amplifier SOP State Of Polarization SPM Self-Phase Modulation SSG Small Signal Gain TM Test Method TTE Terminal Transmission Equipment UV Ultra Violet XPM Cross-Phase Modulation 5 Conventions This clause is intentionally left blank. 6 Purpose of testing in optical fibre submarine cable systems Testing is to be made at different periods in a systems life
