1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationFibre optic active componentsand devices Test and measurement procedures Part 4: Relative intensity noise using a time-domain optical detection systemBS EN 62150-4:2010National f
2、orewordThis British Standard is the UK implementation of EN 62150-4:2010. It isidentical to IEC 62150-4:2009.The UK participation in its preparation was entrusted by Technical CommitteeGEL/86, Fibre optics, to Subcommittee GEL/86/3, Fibre optic systems andactive devices.A list of organizations repre
3、sented 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 2010ISBN 978 0 580 62462 9ICS 33.180.20Compliance with a British Standard cannot confer i
4、mmunity fromlegal obligations.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on 28 February 2010Amendments issued since publicationAmd. No. Date Text affectedBRITISH STANDARDBS EN 62150-4:2010EUROPEAN STANDARD EN 62150-4 NORME EUROPENNE EUROPISC
5、HE NORM January 2010 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: Avenue Marnix 17, B - 1000 Brussels 2010 CENELEC - All rights of exploitation in any form and by
6、any means reserved worldwide for CENELEC members. Ref. No. EN 62150-4:2010 E ICS 33.180.20 English version Fibre optic active components and devices - Test and measurement procedures - Part 4: Relative intensity noise using a time-domain optical detection system (IEC 62150-4:2009) Composants et disp
7、ositifs actifs fibres optiques - Procdures dessais et de mesures - Partie 4: Intensit relative du bruit en utilisant un systme de dtection optique dans le domaine temporel (CEI 62150-4:2009) Aktive Lichtwellenleiter-Bauteile und -Bauelemente - Grundlegende Prf- und Messverfahren - Teil 4: Messung de
8、s relativen Intensittsrauschens unter Anwendung eines optischen Zeitbereichs-Empfangssystems (IEC 62150-4:2009) This European Standard was approved by CENELEC on 2009-12-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this E
9、uropean 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 European Standard exists in three official versions (
10、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 the national electrotechnical committees of Austr
11、ia, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Ki
12、ngdom. BS EN 62150-4:2010EN 62150-4:2010 - 2 - Foreword The text of document 86C/918/FDIS, future edition 1 of IEC 62150-4, 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 62150-4
13、 on 2009-12-01. 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) 2010-09-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2012-
14、12-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 62150-4:2009 was approved by CENELEC as a European Standard without any modification. _ BS EN 62150-4:2010- 3 - EN 62150-4:2010 Annex ZA (normative) Normative references to international publica
15、tions with their corresponding European publications 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 document (including any amendments) appli
16、es. NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies. Publication Year Title EN/HD Year IEC 61280-2-2 -Fibre optic communication subsystem test procedures - Part 2-2: Digital systems - Optical eye pattern, waveform and e
17、xtinction ratio measurement EN 61280-2-2 - IEC 61300-3-6 -Fibre optic interconnecting devices and passive components - Basic test and measurement procedures - Part 3-6: Examinations and measurements - Return loss EN 61300-3-6 - IEC 62007-2 -Semiconductor optoelectronic devices for fibre optic system
18、 applications - Part 2: Measuring methods EN 62007-2 - IEEE 802.3 2005 IEEE Standard for Information technology - Telecommunications and information exchange between systems - Local and metropolitan area networks - Part 3: Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Metho
19、d and Physical Layer Specifications - - ITU-T Recommendation G.957 -Optical interfaces for equipments and systems relating to the synchronous digital hierarchy - - BS EN 62150-4:2010 2 62150-4 IEC:2009(E) CONTENTS INTRODUCTION.5 1 Scope.6 2 Normative references6 3 Terms, definitions and abbreviation
20、s .7 3.1 Terms and definitions 7 3.2 Abbreviations.7 4 Apparatus.8 4.1 General .8 4.2 Time-domain detection system.8 4.3 Polarization controller 8 4.4 Optical coupler 9 4.5 Variable optical attenuator .9 4.6 Fixed reflector .9 4.7 Modulation source .9 4.8 Low-pass filter .9 5 Test procedure .9 5.1 R
21、eturn loss calibration (optional)9 5.2 RIN measurement Direct method 9 5.2.1 General .9 5.2.2 Procedure10 5.3 RINOMAmeasurement Direct method11 5.3.1 General .11 5.3.2 Procedure11 5.4 RIN and RINOMAmeasurement Using signal processing .11 5.4.1 General .11 5.4.2 Procedure11 6 Test results 12 Annex A
22、(informative) Background on laser intensity noise .13 Bibliography14 Figure 1 Equipment setup for RIN measurement .8 Figure 2 Diagram for measuring RIN and RINOMA.10 BS EN 62150-4:201062150-4 IEC:2009(E) 5 INTRODUCTION Laser intensity noise can be one of the limiting factors in the transmission of a
23、nalogue or digital signals. It can reduce the signal-to-noise ratio and increase the bit error rate, therefore degrading system performance. Laser intensity noise can vary significantly depending on the properties of the laser and back reflections. In order to optimize communication links, it is ess
24、ential to accurately characterize the laser intensity noise, compare it with the signal strength, and if necessary allow an appropriate power budget. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. IEC shall not be held responsibl
25、e for identifying any or all such patent rights. The International Electrotechnical Commission (IEC) draws attention to the fact that it is claimed that compliance with this document may involve the use of a patent concerning the FFT method for separating noise and deterministic signals given in 5.4
26、.2. IEC takes no position concerning the evidence, validity and scope of this patent right. The holder of this patent right has assured the IEC that he/she is willing to negotiate licences under reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this resp
27、ect, the statement of the holder of this patent right is registered with IEC. Information may be obtained from: Agilent Technologies 1400 Fountain Grove Parkway Santa Rosa, CA 95404 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights o
28、ther than those identified above. IEC shall not be held responsible for identifying any or all such patent rights. BS EN 62150-4:2010 6 62150-4 IEC:2009(E) FIBRE OPTIC ACTIVE COMPONENTS AND DEVICES TEST AND MEASUREMENT PROCEDURES Part 4: Relative intensity noise using a time-domain optical detection
29、 system 1 Scope This part of IEC 62150 specifies test and measurement procedures for relative intensity noise (RIN). It applies to lasers, laser transmitters, and the transmitter portion of transceivers. This procedure examines whether the device or module satisfies the appropriate performance speci
30、fication. The procedure is applicable to single longitudinal mode (SLM). An optional section of the procedure presents a controlled return loss to the device-under-test, but is only applicable to devices coupled to SMF. The method described in this standard, using a time-domain detection system, pro
31、vides a single value for RIN that averages the noise over the transmission bandwidth. The measurement is made on a modulated laser capturing the RIN value under normal operating conditions. It also measures RINOMA, an alternative definition, as described in IEEE 802.3-2005. An alternative RIN measur
32、ement method uses a photoreceiver and electrical spectrum analyzer and provides RIN vs. electrical frequency. This method provides a RIN value averaged over particular electrical band determined by a filter. For a filter bandwidth and characteristic that duplicates the filtering in a transmission sy
33、stem, this technique provides a result that is appropriate to determine the noise for such a system. This method is based on the measurement of total intensity noise including and does attempt to subtract the effects of thermal and shot noise. Background on laser intensity noise is given in Annex A.
34、 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 document (including any amendments) applies. IEC 61280-2-2, Fibre opti
35、c communication subsystem test procedures Part 2-2: Digital systems Optical eye pattern, waveform and extinction ratio measurement IEC 61300-3-6, Fibre optic interconnecting devices and passive components Basic test and measurement procedures Part 3-6: Examinations and measurements Return loss IEC 6
36、2007-2, Semiconductor optoelectronic devices for fibre optic system applications Part 2: Measuring methods IEEE 802.3TM-2005, Carrier sense multiple access with collision detection (CSMA/CD) access method and physical layer specifications ITU-T Recommendation G.957, Optical interfaces for equipments
37、 and systems relating to the synchronous digital hierarchy BS EN 62150-4:201062150-4 IEC:2009(E) 7 3 Terms, definitions and abbreviations For the purposes of this document, the following terms, definitions and abbreviations apply. 3.1 Terms and definitions 3.1.1 intersymbol interference distortion o
38、f the received signal, which is manifested in the temporal spreading and consequent overlap of individual pulses to the degree that the receiver cannot reliably distinguish between changes of state, i.e., between individual signal elements 3.1.2 optical modulation amplitude difference of the power i
39、n the “1” level to the power in the “0” level on a digital transmission signal 3.1.3 relative intensity noise ratio of the mean-square optical intensity fluctuations over a specified frequency range, normalized to a 1-Hz bandwidth, to the square of the average optical power NNBPPRIN212 (4) f) Calcul
40、ate RINOMAfrom Equation (2). 5.4 RIN and RINOMAmeasurement Using signal processing 5.4.1 General It is sometimes not possible to modulate the laser transmitter with a square wave as described in 5.2.2 c), but instead, the modulation is a PRBS. In that case the “0” and “1” levels consist of two compo
41、nents: (1) the random (Gaussian) component that is required for the RIN and RINOMAcalculations and (2) a deterministic component due to ISI. In this case, signal analysis is required separate the random component from the deterministic component. If the performance specification does not require mea
42、surement for a particular return loss, steps 5.2.2 f) and 5.2.2 g) are omitted. 5.4.2 Procedure This procedure shall be carried out as follows: a) Follow steps 5.2.2 a) through 5.2.2 i). b) If measuring RINOMA, also follow steps 5.3.2 b) through 5.3.2 f). c) To obtain the power and noise values for
43、the calculations, measure the pattern repeatedly and acquire histograms of the “0” and “1” levels. Fit the histogram data to a dual-Dirac model in order to separate random a deterministic components. Use only the random components to derive P1, P0, P1, and P0. Alternatively, the “0” and “1” levels c
44、an be processed through an FFT because they are repetitively sampled. The random component is separated by removing the spectral peaks and integrating the remainder. BS EN 62150-4:2010 12 62150-4 IEC:2009(E) 6 Test results The following information shall be reported for each test: data rate; low-pas
45、s filter bandwidth; return loss presented to laser transmitter (if required); RIN and RINOMAvalues. BS EN 62150-4:201062150-4 IEC:2009(E) 13 Annex A (informative) Background on laser intensity noise In a receiver, laser intensity fluctuations can create noise that exceeds the thermal noise of the lo
46、ad impedance and/or the shot noise of the photodetector. It therefore can become a limiting factor for the power budget of an optical link. If so, then careful characterization of such fluctuations becomes essential to optimize system performance. Intensity fluctuations come primarily from the spect
47、ral properties of a laser. At very low power levels a laser emits mostly spontaneous emission, which, similar to the light coming from an LED, covers a range of wavelengths. Above its lasing threshold, a laser emits mostly stimulated emission and only a small amount of spontaneous emission. The stim
48、ulated emission is concentrated at or around one wavelength and contains most of the power used for sending information along an optical fibre. In a photodetector the stimulated emission interacts with any residual spontaneous emission, effectively creating noise that can be observed electrically. P
49、hotodetectors create an output current that is proportional to the optical power, which in turn is proportional to the square of the electric field. Because of this nonlinear relationship between optical field strength and photodetector current, photons with different optical frequencies create “beat signals.“ The signal “beats“ with the spontaneous emission and the spontaneous emission beats with itself. However, with todays semiconductor lasers a
