1、BRITISH STANDARD BS EN 61290-5-2:2004 Optical amplifiers Test methods Part 5-2: Reflectance parameters Electrical spectrum analyser method The European Standard EN 61290-5-2:2004 has the status of a British Standard ICS 33.180.30 BS EN 61290-5-2:2004 This British Standard was published under the aut
2、hority of the Standards Policy and Strategy Committee on 15 July 2004 BSI 15 July 2004 ISBN 0 580 44067 2 National foreword This British Standard is the official English language version of EN 61290-5-2:2004. It is identical with IEC 61290-5-2:2003. The UK participation in its preparation was entrus
3、ted by Technical Committee GEL/86, Fibre optics, to Subcommittee GEL/86/3, Fibre optic systems and active devices, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which imple
4、ment international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication doe
5、s not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/Europea
6、n committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages
7、 2 to 15 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEAN STANDARD EN 61290-5-2 NORME EUROPENNE EUROPISCHE NORM May 2004 CENELEC European Committee for Electrotechnica
8、l Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2004 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 612
9、90-5-2:2004 E ICS 33.180.30 English version Optical amplifiers Test methods Part 5-2: Reflectance parameters Electrical spectrum analyser method (IEC 61290-5-2:2003) Amplificateurs optiques Mthodes dessai Partie 5-2: Paramtres du facteur de rflexion Mthode de lanalyseur de spectre lectrique (CEI 612
10、90-5-2:2003) Prfverfahren fr Lichtwellenleiter- Verstrker Teil 5-2: Reflexionsparameter Verfahren mit einem elektrischen Spektralanalysator (IEC 61290-5-2:2003) This European Standard was approved by CENELEC on 2004-05-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations
11、 which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This Euro
12、pean Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are
13、the national electrotechnical committees of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and
14、United Kingdom. EN 69210-5-2:0240 - - 2 Foreword The text of document 86C/547/FDIS, future edition 1 of IEC 61290-5-2, prepared by SC 86C, Fibre optic systems and active devices, of IEC TC 86, Fibre optics, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61290-5-2 on
15、 2004-05-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2005-02-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2007-05-
16、01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 61290-5-2:2003 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following notes have to be added for the standards indicated:
17、IEC 60793-1 NOTE Harmonized in EN 60793-1 series (partly modified). IEC 60825-1 NOTE Harmonized as EN 60825-1:1994 (not modified). IEC 60825-2 NOTE Harmonized as EN 60825-1:2000 (not modified). IEC 60874-1 NOTE Harmonized as EN 60874-1:1999 (not modified). _ Page2 BSEN6129052:2004-09216-52 3002:CEI
18、3 CONTENTS FOREWORD 5 1 Scope and object . 9 2 Normative references. 9 3 Abbreviated terms 9 4 Apparatus .11 5 Test sample15 6 Procedure.15 6.1 Input reflectance 15 6.1.1 General15 6.1.2 Calibration .17 6.1.3 OFA input reflectance measurement.21 6.2 Output reflectance .21 6.2.1 General21 6.2.2 Calib
19、ration .23 6.2.3 OFA output reflectance measurement.25 7 Calculation27 8 Test results.27 Bibliography 29 Figure 1 Configurations for electrical spectrum analyser measurement methods for OFA reflectance .11 Figure 2 Configurations for determining polarization controller, optical branching device and
20、optical isolator insertion loss measurement 17 Figure 3 Measurement of OFA input power .19 Figure 4 Measurement of inherent reflectance of test set-up .19 Figure 5 Measurement of the loss of the optical branching device .21 Figure 6 Measurement of input probe power .23 Figure 7 Measurement of the in
21、herent reflectance of the test set-up25 Figure 8 Measurement OFA input signal power .25 Page3 BSEN6129052:2004-09216-52 3002:CEI 9 OPTICAL AMPLIFIERS TEST METHODS Part 5-2: Reflectance parameters Electrical spectrum analyser method 1 Scope and object This part of IEC 61290 applies to optical fibre a
22、mplifiers (OFAs) using active fibres, containing rare-earth dopants, presently commercially available. The object of this part of IEC 61290 is to establish uniform requirements for accurate and reliable measurements, by means of the electrical spectrum analyser test method, of the following OFA para
23、meters, as defined in IEC 61291-1: a) input reflectance; b) output reflectance. NOTE 1 All numerical values followed by () are currently under study. NOTE 2 The measurement uncertainty should be better than 1 dB. 2 Normative references The following referenced documents are indispensable for the app
24、lication of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 61291-1, Optical fibre amplifiers Part 1: Generic specification 3 Abbreviated terms For the purposes of this
25、document, the following abbreviations apply: ASE Amplified spontaneous emission DFB Distributed feedback (laser diode) EA Electro-absorption ESA Electrical spectrum analyser MZ Mach-Zehnder OFA Optical fibre amplifier OSA Optical spectrum analyser Page4 BSEN6129052:2004-09216-52 3002:CEI 11 4 Appara
26、tus The measurement set-ups are shown in Figure 1. dB Variable attenuator Optical branching device Polarization controller OA Terminated port Isolator ESA Receiver Tx Frequency synthesizer Rx Terminated port IEC 2207/03 Figure 1a OFA input reflectance Receiver Tx Frequency synthesizer f1 Optical bra
27、nching device OA Isolator Polarization controller dB Terminated port Polarization beam splitter dB Optical spectrum analyser Rx Electrical spectrum analyser X YIsolator Tx Frequency synthesizer f2 Polarization controller IEC 2208/03 Figure 1b OFA output reflectance Figure 1 Configurations for electr
28、ical spectrum analyser measurement methods for OFA reflectance Page5 BSEN6129052:2004-09216-52 3002:CEI 31 The test equipment listed below, with the required characteristics, is needed. a) Optical source(s): the optical source shall be either at fixed wavelength or wavelength tunable. It shall gener
29、ate light at the wavelength specified in the relevant product specification. The side mode suppression ratio shall be higher than 30 dB. An optical isolator with isolation greater than 40 dB shall be integrated within the source package or connected at the source output. All sources must be linearly
30、 polarized, in order to separate the amplified signal and reflected probe signal in the output port reflectance measurement. This source shall be capable of being directly modulated or externally modulated (that is, Mach-Zehnder (MZ) or electro-absorption (EA) modulators). In some cases, it may be n
31、ecessary to use a power/booster OFA to increase the signal to the appropriate level for measurements. For the output reflectance test, a single laser source split and then externally modulated on each arm can be used to generate the input and probe signal. Likewise, two separate externally or direct
32、ly modulated lasers could generate the signals. The wavelength of the probe shall be within the operating wavelength range of OFA. NOTE 1 A DFB laser or external cavity laser are suitable sources. NOTE 2 The line width of the optical source should not be too narrow to let the interferometric signal
33、due to multiple reflections affect the measurements. b) Frequency synthesizer: the frequency synthesizer shall generate a modulation frequency 10 MHz. The frequency synthesizer may be integral to the transmitter shown or separate from the optical source. c) Optical branching device(s): a 50/50, 90/1
34、0, or other directional coupler is needed with excess insertion loss lower than 0,5 dB () and a directivity no lower than 60 dB. It shall have connectors with reflectance less than 55 dB (). It shall have an output connector of the same type as the OFA input connector. Any unused ports shall have a
35、reflectance lower than 55 dB (). d) Optical power meter: it shall have a measurement accuracy better than 0,2 dB, irrespective of the state of polarization within the operational bandwidth of the OFA. e) Electrical spectrum analyser (ESA): it shall have a frequency range of at least 10 MHz to 500 MH
36、z (). Only the ability to measure moderately fast signals is necessary (above 10 MHz). f) Optical isolator: it shall have an isolation better than 60 dB () and a reflectance from both ports of less than 55 dB (). g) Variable optical attenuator: its attenuation range shall be greater than 40 dB (). I
37、ts accuracy shall be better than 0,1 dB. The reflectance from both ports shall be less than 50 dB. h) Optical fibre jumpers: taking into account the means of connecting the fibres and the mode field diameters, the insertion shall be less than 0,1 dB. Their length should be 2 m to 4 m. If the jumper
38、is connected directly to the OFA, the connector shall have the same characteristics as that of the OFA port. i) Optical connectors: the connection loss repeatability shall be less than 0,2 dB. Their reflectance shall be lower than 55 dB. j) Terminated ports: the reflectance from terminated ports sha
39、ll be lower than 60 dB. k) Receiver: it shall have a less than 0,05 dB polarization dependence. Internal electrical amplifiers shall enable a greater than 50 dB () dynamic range for receiver input power (that is, the difference between receiver saturation and its thermal noise floor). This receiver
40、may necessitate two electrical amplifiers to ensure probe signal detection. l) Polarization beam splitter: a polarization beam splitter that splits into two orthogonal polarizations with 40 dB polarization extinction ratio at each polarization state. Page6 BSEN6129052:2004-09216-52 3002:CEI 51 m) Op
41、tical spectrum analyser: the polarization dependence of the spectral power measurement shall be better than 0,1 dB (). The spectral resolution shall be equal to, or better than, 0,1 nm. Note that the linearity and accuracy of this measurement are not important since it is only used to optimize the p
42、olarization of the amplified signal to a desired orthogonal polarization. Alternatively, an optical power meter with an appropriate signal selection filter may be used. n) Polarization controller: This device shall be able to provide input signal light at all possible states of polarization (for exa
43、mple, linear, elliptical and circular). The polarization controller may be an all-fibre-type device or a quarter-wave plate rotatable by a minimum of 90 and a half-wave plate rotatable by a minimum of 180. The loss variation of the polarization controller shall be less than 0,1 dB (). The reflectanc
44、e from this device shall be smaller than 40 dB () at each port. 5 Test sample The OFA shall operate at nominal operating conditions. Care shall be taken in maintaining the state of polarization of the input light after it is adjusted to the “worst case” possible. Changes in the polarization state ma
45、y result in changes in the gain as well as the noise due to multipath interference. NOTE 1 The output reflectance test procedure should only be performed on OFAs that have the complete optics (that is, have sufficient attenuation in the direction opposite the signal). This measurement is of little o
46、r no value for OFA devices that do not have all the optics for “black-box” OFA ready for use in an optical communications system. NOTE 2 The reflectance at each port of the OFA may depend on the optical gain and consequently on signal and pump power. NOTE 3 Polarization dependence of the reflection
47、parameters is not considered as important as the magnitude of the reflection. 6 Procedure 6.1 Input reflectance 6.1.1 General This method enables the determination of the OFA input reflectance with the use of an optical branching device, isolator, receiver, and an ESA. Note that reverse ASE power at
48、 the signal wavelength will not impact the input reflectance measurement on the ESA. Page7 BSEN6129052:2004-09216-52 3002:CEI 71 Tx dB Receiver ESA Variable attenuator Rx IEC 2209/03 Figure 2a Source electrical power measurement Tx dB Variable attenuator Polarization controller Optical branching dev
49、ice Terminated portIsolator Rx Receiver ESA 1 2 3 4 Terminated port IEC 2210/03 Figure 2b Polarization controller, optical branching device, and isolator throughput measurement Figure 2 Configurations for determining polarization controller, optical branching device and optical isolator insertion loss measurement 6.1.2 Calibration 1) D
