1、Optical amplifiers Testmethods Part 3: Noise figure parametersBS EN 61290-3:2008raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI British StandardsLicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSINat
2、ional forewordThis British Standard is the UK implementation of EN 61290-3:2008. It isidentical to IEC 61290-3:2008. It supersedes BS EN 61290-3:2000 which iswithdrawn.The UK participation in its preparation was entrusted by Technical CommitteeGEL/86, Fibre optics, to Subcommittee GEL/86/3, Fibre op
3、tic systems andactive devices.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application. BSI 2009ISBN 978 0 580 58630 9ICS
4、33.180.30BRITISH STANDARDBS EN 61290-3:2008Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on Amendments issued since publicationAmd. No. Date Text affectedMarch 2009
5、31Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSIEUROPEAN STANDARD EN 61290-3 NORME EUROPENNE EUROPISCHE NORM October 2008 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches K
6、omitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61290-3:2008 E ICS 33.180.30 Supersedes EN 61290-3:2000English version Optical amp
7、lifiers - Test methods - Part 3: Noise figure parameters (IEC 61290-3:2008) Amplificateurs optiques - Mthodes dessais - Partie 3: Paramtres du facteur de bruit (CEI 61290-3:2008) Lichtwellenleiter-Verstrker - Prfverfahren - Teil 3: Rauschzahlparameter (IEC 61290-3:2008) This European Standard was ap
8、proved by CENELEC on 2008-10-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations 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 na
9、tional standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European 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 langu
10、age and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latv
11、ia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 61290-3:2008Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSIEN 61290-3:2008 2 Foreword
12、 The text of document 86C/842/FDIS, future edition 2 of IEC 61290-3, 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 61290-3 on 2008-10-01. This European Standard supersedes EN 61
13、290-3:2000. EN 61290-3:2008 includes updates to specifically address additional types of optical amplifiers and to highlight that the EN 61290-3 series pertains to single-channel amplifiers. References have been added to the documents pertaining to multichannel amplifiers. The following dates were f
14、ixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2009-07-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2011-10-01 Annex ZA has been added by CENELEC.
15、_ Endorsement notice The text of the International Standard IEC 61290-3:2008 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following note has to be added for the standard indicated: IEC 61290-10 NOTE Harmonized in EN 61290-10
16、series (not modified). _ BS EN 61290-3:2008Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSI 3 EN 61290-3:2008 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following refere
17、nced documents are indispensable for the application 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. NOTE When an international publication has been modified by common mo
18、difications, indicated by (mod), the relevant EN/HD applies. Publication Year Title EN/HD Year IEC 61290-3-1 - 1)Optical amplifiers - Test methods - Part 3-1: Noise figure parameters - Optical spectrum analyzer method EN 61290-3-1 2003 2)IEC 61290-3-2 - 1)Optical amplifiers - Test methods - Part 3-2
19、: Noise figure parameters - Electrical spectrum analyzer method EN 61290-3-2 2008 2)IEC 61291-1 - 1)Optical amplifiers - Part 1: Generic specification EN 61291-1 2006 2)1) Undated reference. 2)Valid edition at date of issue. BS EN 61290-3:2008Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17
20、/06/2009 04:19, Uncontrolled Copy, (c) BSI 2 61290-3 IEC:2008 CONTENTS INTRODUCTION.5 1 Scope and object6 2 Normative references .6 3 Acronyms and abbreviations.6 4 Noise figure generalities.7 5 Noise figure contributions.8 6 Noise figure test methods.9 Bibliography11 Table 1 Parameters measurable w
21、ith each of the two methods of Clause 510 BS EN 61290-3:2008Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSI61290-3 IEC:2008 5 INTRODUCTION This International Standard is devoted to the subject of optical amplifiers. The technology of optical amplif
22、iers is still evolving, hence amendments to and new editions of this standard can be expected. Each abbreviation introduced in this standard is explained in the text at least the first time it appears. However, for an easier understanding of the whole text, a list of all abbreviations used in this s
23、tandard is given in Clause 3. BS EN 61290-3:2008Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSI 6 61290-3 IEC:2008 OPTICAL AMPLIFIERS TEST METHODS Part 3: Noise figure parameters 1 Scope and object This International Standard applies to all commerc
24、ially available optical amplifiers (OAs), including OAs using optically pumped fibres (OFAs based on either rare-earth doped fibres or on the Raman effect), semiconductor optical amplifiers (SOAs) and planar waveguide optical amplifiers (PWOAs). The object of this standard is to provide the general
25、background for OA noise figure parameters measurements and to indicate those IEC standard test methods for accurate and reliable measurements of the following OA parameters, as defined in IEC 61291-1: a) noise figure (NF); b) noise factor (F); c) multiple path interference (MPI) figure of merit; d)
26、signal-spontaneous noise figure; e) (equivalent) spontaneous-spontaneous optical bandwidth (Bsp-sp); f) forward amplified spontaneous emission (ASE) power level; g) reverse ASE power level; h) ASE bandwidth. This standard addresses measurement of OAs that are to be used for amplifying single channel
27、s, that is signals from a single transmitter. Testing of OAs for multichannel use involves additional considerations, such as: the number, wavelengths and relative power of the signals, the ability to measure signals simultaneously and to measure the ASE between channels. NOTE Methods for measuremen
28、t of OAs for multichannel use are included in the IEC 61290-10 series. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced
29、document (including any amendments) applies. IEC 61290-3-1, Optical amplifiers Test methods Part 3-1: Noise figure parameters Optical spectrum analyzer method IEC 61290-3-2, Optical amplifiers Part 3-2: Test methods for noise figure parameters Electrical spectrum analyzer method IEC 61291-1, Optical
30、 amplifiers Part 1: Generic specification 3 Acronyms and abbreviations ASE amplified spontaneous emission Bsp-sp(equivalent) spontaneous-spontaneous optical bandwidth BS EN 61290-3:2008Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSI61290-3 IEC:2008
31、 7 ESA electrical spectrum analyzer F noise factor FWHM full width half maximum MPI multiple path interference NF noise figure OA optical amplifiers OFA optical fibre amplifier OSA optical spectrum analyzer PWOA planar waveguide optical amplifiers SOA semiconductor optical amplifiers SNR signal-to-n
32、oise ratio 4 Noise figure generalities The noise figure is one of the most important parameters of an OA. Following the definition in IEC 61291-1, the noise factor, i.e. the linear form of the noise figure, can be expressed by: in2noiseout2noise2out2signalout2noisein2noisein2signaloutputinput1=iiGFi
33、iiiSNRSNRF(1) where SNR denotes signal-to-noise ratios; i denotes photocurrents in an ideal photodetector with a quantum efficiency of 1; G denotes the optical signal gain. The input noise current is, by definition, the shot noise current caused by the optical input signal. This excludes other noise
34、 sources on the input side. The output noise current is the sum of five contributions. Each of these contributions can be expressed by a partial noise factor: a) signal shot noise factor, Fshot,sig, from shot noise from amplified input signal; b) ASE shot noise factor, Fshot,ase, from shot noise fro
35、m amplified spontaneous emission; c) signal-spontaneous noise factor, Fsig-sp, from signal beating with ASE; d) spontaneous-spontaneous noise factor, Fsp-sp, from ASE beating with itself; e) noise factor from multiple path interference (MPI), Fmpi. The total noise factor (in linear, not logarithmic
36、units) is: mpispspspsigaseshot,sigshot,totalFFFFFF +=(2) BS EN 61290-3:2008Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSI 8 61290-3 IEC:2008 The noise figure can be calculated using: ()totallog10 FNF = (3) Equation (2) can be used for optical nois
37、e figure measurements, as well as for estimating the influence of various parameters in electrical noise figure measurements. It represents a complete noise figure model of an OA. 5 Noise figure contributions The signal shot noise factor is: GF1sigshot,= , (4) where G is the gain at the signal wavel
38、ength. The ASE shot noise factor is: in2aseaseshot,PGPF = (5) where Paseis the wavelength-integrated ASE power; Pinis the optical input signal power. The signal-spontaneous noise factor is: sigpase,spsigh2GF =(6) where ase,pis the optical power density of spontaneous emission, in the same polarizati
39、on state as the output signal, at the signal wavelength, in W/Hz; h is Plancks constant; sig= c/sigis the optical signal frequency, in Hz. The spontaneous-spontaneous noise factor is: in2sigspsp2asespsph2 PGBF= (7) where aseis the optical power density of total (unpolarized) spontaneous emission, at
40、 the signal wavelength, in W/Hz; Bsp-sp is the equivalent spontaneous-spontaneous optical bandwidth defined in IEC 61291-1; it depends on power and wavelength of input signal. NOTE When Bsp-spis known, there is no need for separate measurement of Fsp-spbecause it can be calculated from the signal sp
41、ontaneous noise factor and the input power. Since ASE in any polarization state contributes to BS EN 61290-3:2008Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 17/06/2009 04:19, Uncontrolled Copy, (c) BSI61290-3 IEC:2008 9 Fsp-sp, this calculation also needs additional information if the ASE
42、 is not unpolarized, as is typical for example for SOAs. Multiple path interference (MPI) noise is generated by beating between the output signal and one or more doubly reflected replica of the output signal. Two or more reflection points inside the OA are necessary to generate MPI noise. When all r
43、eflection points are separated by more than the coherence length of the optical source, then the MPI noise factor is as follows: ()+=iGpfPFicav,i22inmpih2(8) where Gcav,iis the cavity gain (gain in the ithparasitic cavity in the OA) = gain in forward direction reflectivity in forward direction gain
44、in backward direction reflectivity in backward direction; piis the polarization alignment factor, and expresses the matching of polarization states between the direct and doubly reflected signal in the ithcavity (between 0 and 1, p = 1 for perfect alignment); piGcav,iis the effective cavity gain of
45、the ithcavity; is meant to collect all possible cavity gains in the OA; is the FWHM of the source linewidth (Lorentzian model); f is the baseband frequency. When two or more light beams are coherent with each other, i.e. generated by closely spaced reflection points, MPI cannot be considered as nois
46、e, but rather as slow power fluctuations. In these cases, MPI does not contribute to the NF. The MPI contribution to the noise factor depends on the linewidth of the source, , a parameter of the transmission system or measurement apparatus but not on the OA. To remove this parameter from the OA nois
47、e factor, it is suggested to integrate the MPI noise factor and denote the integration result a figure of merit, Impi, for the MPI characteristics of the OA. Impirepresents the area under the Fmpicurve; it does not depend on the linewidth of the source or the baseband frequency: ()=ifGpPfFIicav,iin0
48、mpimpihdHz (9) where the MPI noise factor can be calculated from the figure of merit using: 22mpimpi2+=fIF (10) A special form of MPI known as double-Rayleigh scattering can be a significant factor in Raman fibre amplifiers, where long spans of fibre can provide gain for the small amount of signal t
49、hat is backscattered by the Rayleigh effect in fibre, rather than due to reflections. 6 Noise figure test methods Two qualitatively different and commonly practised procedures for quantifying the noise figure of an OA are considered in this standard. The aim of the first procedure (see IEC 61290-3-1) is to determine the signal-spontaneous noise figure. This method uses an optical spectrum analyzer to determine gain and spectral
