1、STDaEIA SP NO 3b7b-ENGL 2000 3234hDO 065h520 295 811 May 26,2000 2500 Wilson Boulevard, Suite 300 Arlington, VA 22201 703/907-7700 FAX 703/907-7727 Representing the telecommunications industry in association with the Electromc Industries Alliance Copyright Telecommunications Industry Association Pro
2、vided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-PLEASE FILL OUT AND SIGN THIS FORM AND RETURN IT WITH ANY COMMENTS TO: Billie Zidek-Comer Telecommunications Industry Assoc. 2500 Wilson Blvd., Suite 300 Arlington, VA 22201 -3834 (F
3、AX: 703/907-7727) SUBJECT: Standards Proposal No. 3696, Proposed New Standard “Accelerated Measurement of BER and Q-Factor in Digital Optical Transmission Systems Using the Sinusoidal Interference Method” (if approved, to be published as TWEL4-526-8) COMMENT PERIOD EXPIRES: JULY 26,2000 PRODUCER I G
4、ENERAL INTEREST of the relevance of this This information is re -page 2- Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,- - STD.EIA SP NO 3696-ENGL 2000 3234600 065h522 068 H NO
5、TICE This document is a TWEIA Engineering Standards Proposal, rather than an interim or final Standard. It is published for purposes of comment and is subject to further review and modification by the TLA Technical Standards Subcommittee (TSSC), which may accept or reject the Standards Proposal. Acc
6、ordingly, readers of this Standards Proposal are cautioned against contained therein prior to the adoption of a final standard. TMIA disc1 responsibility for the consequences of such reliance. ion or TELECOMMUNICATIONS INDUSTRY 2500 Wilson Boulevard Copyright Telecommunications Industry Association
7、Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,- STD=EIA SP NO 3bqb-ENGL 2000 W 3234b00 Ob5b523 TT4 I1Ip SP-3696 (To be TINEIA-526-8) Section Sinusoidal Interference Meth 1 Introduction 2 Normative references 3 Appartus OFSTP-8
8、 Accelerated Measurement of BER and Q-Fa Digital Optical Transmission Systems U 5 4 S 5 P 3 4 b 4 erpretation ts 9 8 9 oidal Interference Method by Optical Injection 6 for the Sinusoidal Interference Method by Electrical Injection 7 b Result from the Sinusoidal Interference Method 10 11 R vs Optical
9、 Power for Three Methods A Comparison between OFSTP-8 and IEC and ITU requirements 12 RLN, TIA SC F0-2.1,5/00 I Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-STD*EIA SP NO 3bq
10、b-ENGL 2000 3234600 065652Y 930 1911 SP-3696 (To be TINEIA-526-8) OFSTP-8 Accelerated Measurement of BER and Q-Factor in Digital Optical Transmission Systems Using the Si n u soi d al 1 n te rfe re n ce Method of very low bit-error ratios educe the time required to 1 espe it-rates. The usual methods
11、 can -i2 in which optical power is varied, in this varying disturbance, representing noise, is I noise, shot noise, reflection-induced noise, laser se, crosstalk, jitter, etc. The sum of all noise sources tribution. The technique may not be applicable if the BER is astic processes, such as rare impu
12、lse noise. Its applicability with amplified spontaneous emission (ASE) is under study. The r or not a BER “floor“ is present. Such a floor is due to the signal- ,eing almost independent of the input power to the receiver. The method artificially degrades the di ita1 channel in a controlled manner, t
13、hereby raising the BER to a range (such as IO- to IO- ) within which the measurement time is substantially reduced. Values of BER vs. the amount of artificial degradation are recorded and then extrapolated to the poiiit of zero artificial degradation. The results of the optical sinsusoidal ?o RLN, T
14、IA SC FO-2.1, 5/00 3 Previous page is blank Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SP-3696 (To be TINEIA-526-8) interference method and the variable threshold method of
15、 OFSTPQ have been shown to agree with each other. 1.2.1 Sinusoidal interference method: This method optically or electrically adds an interfering sinusoidal signal to the digital signal at a point before the receiver (Rx) decision circuit to increase the measured BER. The measurements taken at sever
16、al value The sinusoid can be injected into the Rx optically, by adding it to the o the sinusoid electrically requires electrical access to the circuitry of the The optical method works for an ac-coupled Rx only; the electri dc-coupled Rx. 2 Normative references asurement equipment: a BER pattern gth
17、 similar to the system under test and capable of being modulated at a in the passband of the Rx under test. This serves as an “interfering laser”. 3.1.3 An optical splitter/combiner with split ratios typically between 5050 and 1090, and with fiber compatible with that of the system and the interferi
18、ng laser. 3.1.4 An analog optical receiver capable of detecting frequencies within the passband of the system under test, used to confirm proper operation of the interfering laser. RLN, TIA SC FO-2.1,5/00 4 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot f
19、or ResaleNo reproduction or networking permitted without license from IHS-,-,-STD-EIA SP NO 3676-ENGL 2000 3234600 0656526 703 118 SP-3696 (To be TINEIA-526-8) 4 Sampling and specimens The specimen is a fiber optic digital system consisting of a digital transmitter (Tx) receiver (Rx). In between the
20、m is either a fiber link consisting of fiber or cable passive or active components (if an operational link is to be tested) or a attenuator (if the Tx/k pair alone is to be tested). 5 Procedure 5.1 Refer to Figure 1. Sinusoidal Interference Method (Optical O 5.1.1 Place the combiner with one input I
21、 Connect the output port to the Rx and th modulated by the sinewave generator. Con 5.1.2 Adjust the Tx the attenuator is use the duration oft 5.1.3 Choose and not harmonicallv r( ratio or the modulation depth of the interfering laser a step at a time by adjusting the output level of the sinewave gen
22、erator, and at each step record the BER with the error detector. RLN, TIA SC FO-2.1, 5/00 5 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-STDmEIA SP NO 3696-ENGL 2000 H 323460
23、0 - 0656527 _ b4T-M SP-3696 (To be TINEIA-526-8) Setup for the Sinusoidal Interference Method 5.1.6 Measure at least 5data pairs, wit following is an example: 4.6 X al Interference Method (Electrical Option) Refer to Figure 2. 5.2.1 Ac-couple the sinewave generator to the decision threshold input of
24、 the comparator in the Rx under test. Refer to Figure 2, sinewave generator option. if the comparator has differential data inputs, a large series resistor can be used to isolate the comparator data signal from the sinewave generator. If isolation is difficult to achieve, use the threshold modificat
25、ion method of RLN, TIA SC FO-2.1, 5/00 6 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-STD-EIA SP NO 3b9b-ENGL 2000 H 3234b00 Ob56528 5Bb H SP-3696 (To be TINEIA-526-8) OFSTP-
26、9. 5.2.2 Adjust the Tx and Rx to the desired operating conditions. Adjust the data pattern and (if the attenuator is used) the received power to be constant for the duration of the measurement procedure. 5.2.3 Choose the frequency of the sinewave generator to be well within the pa: and not harmonica
27、lly related to the bit-rate. It should be significantly different (s from the bit-rate so that no slow beat phenomena are possible. The freque well above the range of any AGC or threshold tracking loop in the Rx. 5.3.4 Adjust the amplitude of the sinewave generator until a BER of reached. 5.3.5 Decr
28、ease the amplitude of the interference one st of the sinewave generator. At each step, record the E data should be similar to that in Section 5.1.6. jS Figure 2 Setup for the Sinusoidal Interference Method by Electrical Injection RLN, TIA SC FO-2.1, 5/00 - 7 Copyright Telecommunications Industry Ass
29、ociation Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SP-3696 (To be TINEIA-526-8) 6. Calculations and interpretation of results 6.1 Sinusoidal Interference Method 6.1 .I 5.2. the function: These calculations apply for both
30、the optical and electrical options Denote the data pairs collected in 5.1.6 as (Ai, BER$. Transform I where xt = ln(2 * BE&) and where c1 = 0.4926, c2 6.1.2 Fit a straight line to the values Y(BRi ) vs. Ai . Ext A, = O, giving the value Y(5R0) = Q . (Th than 1 O4 because of the erfc approximation mu
31、ch hiaher than 1 05.) Fiaure 3 is an exan urve is not a very g 1 IV Calculate the system BER as: This is the esti approximation to erfc6 to Receiv under test is operating. The above error rates of interest. ults to be expected using the above extrapolation ured by 3 techniques: I interference method
32、 of OFSTP-9 function fit to the measured data using best estimates for the noise of ent of Received Power and the noise from the Tx, which is proportional 7 Documentation 7.1 The following information shall be reported with each test: RLN, TIA SC FO-2.1, 5/00 8 Copyright Telecommunications Industry
33、Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,- STD-EIA SP NO 3696-ENGL 2000 3234600 0656530 134 ia SP-3696 (To be TINEIA-526-8) 7.1 .I Date of test. 7.1.2 Specimen identification. 7.1.3 OFSTP number 7.2 United Sta
34、tes military applications require that the following inform for each test. For other (nonmilitary) applications, this information need no be available for review upon request: 7.2.1 Type of Tx. 7.2.2 Type of Rx. 8 Specification information The following details shall be specified in the 8.1 OFSTP nu
35、mber 8.2 Any special t 8.3 Failure RLN, TIA SC F0-2.1,5100 - 9 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. STD. EIA SP NK3bSb-ENGL 000 3234b00 - - 065b533 070 -5- SP-3696
36、(To be TINEIA-526-8) 10 RLN, TIA SC FO-2.1,5/00 10 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,- STD-EIA SP NO 3b9b-ENGL 2000 1818 3234600 0656532 TO7 SP-3696 (To be TINEIA-5
37、26-8) RLN, TIA SC FO-2.1, 5/00 11 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SP-3696 (To be TINEIA-526-8) Appendix A (informative) Comparison between OFSTP-8 and IEC and IT
38、U requirements Al introduction One of TIAS policy objectives is to promote, whenever possible, th fiber-optic standards. This Annex gives the user of this OFSTP an indication of been adopted, or are in preparation, by IEC and ITU. This Annex is nonmandatory and is for general inform cited references
39、, plus available follow-up data, to determ proposed since the printing of this OFSTP. A2 IEC documents None. However, the topi procedure should be of interest there. B.3 iTU do None. However, the ., BER lev fiber n SGI5, WP4 since the specified m IO- to IO-*. Generally, for components, pruceuures. R
40、LN, TIA SC FO-2.1, 5/00 12 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-STD-EIA SP NO 3696-ENGL 2000 3234600 ObCb534 BBT SP-3696 (To be TINEIA-526-8) OFSTP BACKGROUND DATA Fi
41、ber Optic Test Procedures Proposed as Addendums to EIAiIA-526 This data is for background information only, and is not a permanent part of the OFSTP being balloted. Rick Neumann Picolight Inc. voice: 303-530-31 89 CommerciallMilitarvlFederal Test Methods:. 1 than given kboratory use. * and manufactu
42、ring processes. * # for manufacturina level testina. # I 1 # Reoresentative Manufacturers When Used )earth Council of Canada 1995 RDTE oration 1996 Comments on Accuracy (or potential accuracy), repeatability, etc. of the OFSTP: (if precision and bias statements are not included in the OFSTP) RLN, TIA SC FO-2.1, 5/00 13 Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-