1、BRITISH STANDARD BS EN 60510-3-4:1996 IEC 510-3-4: 1992 Methods of Measurement for radio equipment used in satellite earth stations Part 3: Methods of measurement on combinations of sub-systems Section 3.4 Measurements for frequency division multiplex (f.d.m.) transmission The European Standard EN 6
2、0510-3-4:1994 has the status of a British Standard ICS 33.060.30BSEN 60510-3-4:1996 This British Standard, having been prepared under the directionof the Electrotechnical Sector Board, was published underthe authority of the Standards Board and comes intoeffect on 15August1996 BSI 12-1999 The follow
3、ing BSI references relate to the work on this standard: Committee reference EPL/12/5 Draft announced in BSI News Update September 1995 ISBN 0 580 26115 8 Committees responsible for this British Standard The preparation of this British Standard was entrusted by Technical Committee EPL/12, Radio commu
4、nication, to Subcommittee EPL/12/5, Radio communication systems, upon which the following bodies were represented: British Broadcasting Corporation British Radio and Electronic Equipment Manufacturers Association British Telecommunications plc ERA Technology Ltd. Institution of Electrical Engineers
5、Radio, Electrical and Television Retailers Association Radiocommunications Agency Amendments issued since publication Amd. No. Date CommentsBSEN 60510-3-4:1996 BSI 12-1999 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN 60510-3-4 3 List of referen
6、ces Inside back coverBSEN 60510-3-4:1996 ii BSI 12-1999 National foreword This Section of BSEN 60510 has been prepared by Subcommittee EPL/12/5 and is the English language version of EN 60510-3-4:1994 Methods of measurement for radio equipment used in satellite earth stations Part 3: Method of measu
7、rement on combinations of sub-systems Section 4: Measurements for frequency division multiplex (f.d.m.) transmission published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC 510-3-4:1992, published by the International Electrotechnical Commission (
8、IEC). This standard is published in three Parts. The other Parts are: Part 1: Methods common to sub-systems and combinations of sub-systems; Part 2: Measurements for sub-systems. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are
9、 responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references Publication referred to Corresponding British Standard IEC 50(55):1987 BS 4727 Glossary of electrotechnical, power, telecommunication, electronic
10、s, lighting and colour terms Part 3 Terms particular to telecommunications and electronics Group 01:1971 aGeneral telecommunication and electronics terminology a IEC 50(55): 1987 has not been implemented as a British Standard. The cross-reference cited is technically equivalent to an earlier edition
11、 of that standard. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages 2 to 18, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicat
12、ed in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 60510-3-4 June 1994 UDC 621.396.6:629.783:621.317.08 Descriptors: Radiocommunications, telecommunications, satellite broadcasting, radio equipment, earth stations, characteristics, measurements,
13、telephones, multiplexing English version Methods of measurement for radio equipment used insatellite earth stations Part 3: Methods of measurement on combinations of sub-systems Section 4: Measurements for frequency division multiplex(f.d.m.) transmission (IEC 510-3-4:1992) Mthodes de mesure pour le
14、s quipements radiolctriques utiliss dans les stations terriennes de tlcommunication par satellites Partie 3: Mthodes de mesure applicables aux combinaisons de sous-ensembles Section quatre: Mesures pour la transmission de la tlphonie multivoie multiplexage par rpartition en frquence (m.r.f.) (CEI 51
15、0-3-4:1992) Meverfahren fr Funkgert in Satelliten-Erdfunkstellen Teil 3: Meverfahren fr Kombinationen von Untersystemen Hauptabschnitt Vier: Messungen fr Frequenzmultiplex (FDM)-bertragung (IEC 510-3-4:1992) This European Standard was approved by CENELEC on 1994-03-08. CENELEC members are bound to c
16、omply 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 national standards may be obtained on application to the Central
17、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 language and notified to the Central Secretariat has the same status
18、as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Ele
19、ctrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1994 Copyright reserved to CENELEC members Ref. No. EN 60510-3-4:1994 EEN 60510-3-4:1994 BSI 12-1999 2 Foreword The
20、CENELEC questionnaire procedure, performed for finding out whether or not the International Standard IEC 510-3-4:1992 could be accepted without textual changes, has shown that no common modifications were necessary for the acceptance as European Standard. The reference document was submitted to the
21、CENELEC members for formal vote and was approved by CENELEC as EN 60510-3-4 on8March 1994. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. Annexes designated “informative” are given only for information. In this standard, Appendix A is informative
22、 andAnnex ZA is normative. Contents Page Foreword 2 1 Scope 3 2 Noise-loading performance 3 3 Continuity pilot and out-of-band noise (o.b.n.) 8 4 Periodic noise 9 5 Intelligible crosstalk 10 6 References 11 7 Bibliography 11 Appendix A (informative) Conversion of the measured n.p.r. to noise power l
23、evel or signal-to-noise ratio 16 Annex ZA (normative) Other international publications quoted in this standard with the references of the relevant European publications 18 Figure 1 Principle of the white noise test set 12 Figure 2 Example of noise performance as a function of white noise loading: no
24、ise power ratio measurement 13 Figure 3 Example of noise performance as a function of white noise loading: noise power level or weighted signal-to-noise measurement 13 Figure 4 Typical test arrangement for measuring system n.p.r. variation 14 Figure 5 Arrangement for measuring out-for-band noise and
25、 continuity pilot level 14 Figure 6 Arrangement for measuring intelligible crosstalk ratio 15 Table 1 Level of the conventional load 4 Table 2 Recommended filter frequencies 5 Table 3 Recommended frequencies 9 Table A.1 16 latest date of publication ofan identical national standard (dop) 1995-03-15
26、latest date of withdrawal ofconflicting national standards (dow) 1995-03-15EN 60510-3-4:1994 BSI 12-1999 3 1 Scope This section deals with baseband-to-baseband measurements for frequency division multiplex (f.d.m) telephony. These measurements are additional to those already given in part1, section
27、4 of this publication: Measurements in the baseband, which are common to telephony and to television, for example group-delay and amplitude/frequency characteristics. All of the following measurements are carried out on a system loop either by establishing a transmission path through the transmittin
28、g and receiving chain via a test loop translater or by means of an i.f. loop. 2 Noise-loading performance 2.1 Definitions and general considerations The noise-loading performance of a system is the noise power measured in a chosen narrow measuring channel, which simulates an unloaded telephone chann
29、el, when the baseband is loaded with random noise of uniform spectrum (white noise) at a conventional loading level (see2.1.1). The white noise applied to the baseband input of the system under test is limited to the frequency band occupied by the telephone channels by means of a high-pass and a low
30、-pass filter. Noise-measuring channels are provided by means of narrow band-stop filters which allow performance to be measured at several frequencies including channels located close to the bottom, middle and top of the baseband, frequency range. The total noise appearing within a noise-measuring c
31、hannel at the system output comprises basic noise and intermodulation noise (sometimes referred to as “idle noise” and “distortion noise” respectively). It is, therefore, common practice to measure the noise within each noise-measuring channel with the baseband loaded with noise and then unloaded, i
32、n order to obtain the total noise and basic noise separately; from these results the intermodulation noise may be obtained. The noise performance may be expressed as a noise power ratio (n.p.r.), a signal-to-noise ratio, in units of noise power or noise power level referred to the system zero relati
33、ve level point. The units used may be picowatts, decibels above 1 pW or decibels below 1mW, and they may be specified as a weighted or unweighted psophometric value. Noise power ratio is defined as the ratio of the noise power in a measuring channel when the baseband is fully loaded with the white n
34、oise load, to the power in that channel either with all the baseband loaded except the measuring channel (i.e.total noise) or with all the baseband unloaded (i.e.basic noise); n.p.r. is always expressed as a positive number of decibels. Signal-to-noise ratio is defined as the ratio of the power of t
35、he standard test tone (0dBm0) to the noise power, in a specified bandwidth within the noise-measuring channel, both being referred to the same point in the circuit. Signal-to-noise ratio may be measured weighted or unweighted and is expressed as a positive number in decibels. Conversion between comm
36、only encountered noise-loading measurement units may be made by reference toAppendix A. 2.1.1 Conventional load The conventional loading level, which is defined by the CCITT (reference 1, seeclause6) and recommended by the CCIR (reference 2, see clause 6), is shown inTable 1 for some typical channel
37、 capacities. For other channel capacities the mean power level L cof the conventional load may be calculated from the following expressions: where N is the system channel capacity. NOTE 1These levels simulate the mean power of speech plus signalling currents, etc., transmitted over the system during
38、 the busy hour. Where a significant proportion of the baseband is used for v.f. telegraphy or data transmission, these expressions do not apply. NOTE 2Equations 2-1 and 2-2 give a good approximation to actual signals when N U 60. For smaller channel capacities, however, tests with white noise are le
39、ss realistic owing to the differing nature of actual signals and test signals. L c= 15 + 10 log 10N dBm0 for N U 240 (2-1) L c= 1 + 4 log 10N dBm0 for 12 k N 240 (2-2)EN 60510-3-4:1994 4 BSI 12-1999 Table 1 Level of the conventional load A conventionally loaded system is one which is loaded at the c
40、onventional loading level with a uniform spectrum random noise signal which is band-limited to correspond with the total bandwidth of the f.d.m. signal. The test signal level, in most cases, is chosen to equal the conventional load. 2.1.2 Noise components The total noise measured within the baseband
41、 of a simulated satellite system includes the following three components: a) Residual noise which is independent of path attenuation and loading. This is normally referred to as path-loss-independent basic noise. b) Thermal noise which varies with path attenuation. This is normally referred to as pa
42、th-loss-dependent basic noise. c) Intermodulation noise which is dependent upon the baseband noise loading level. Basic noise a)+b) is measured without noise loading as described below in2.3.4. Total noisea)+b)+c) is measured with noise loading as described below in2.3.2 or2.3.3. 2.2 Measuring equip
43、ment 2.2.1 General considerations Equipment for the measurement of noise-loading performance is commercially available and known either as “white noise test sets” or “noise-loading test sets”. A white noise test set comprises a noise generator and a noise receiver; a typical circuit arrangement is s
44、hown inFigure 1. To ensure test equipment compatibility and to achieve good measurement accuracy, the relevant characteristics of white noise test sets are closely specified by both CCIR (reference 2, seeclause6) and the CCITT (reference 3, see clause6). Commercial white noise test sets are normally
45、 sufficiently accurate for measurements on simulated satellite systems without making allowance for test equipment errors. However, where the required accuracy of measurement is comparable with the intrinsic accuracy of the test equipment, due allowance for measurement error should be made in the pr
46、esentation of results. Measurement accuracy depends upon many factors, including the following: generator and receiver attenuator and monitor accuracies; number of band-stop filters inserted and the effective bandwidths of the noise-measuring channels; region of the loading curve at which the measur
47、ement is being made (i.e.whether basic or intermodulation noise predominates); Number of telephone channels Level of the conventional load (dBm0) 24 36 60 72 96 132 192 252 312 372 432 492 552 612 792 972 1 092 1 872 + 4,5 + 5,2 + 6,1 + 6,4 + 6,9 + 7,5 + 8,1 + 9,1 + 9,9 + 10,7 + 11,4 + 11,9 + 12,4 +
48、 12,9 + 14,0 + 14,9 + 15,4 + 17,7EN 60510-3-4:1994 BSI 12-1999 5 order of distortion predominant in the system under test. These factors are discussed in references3 and4 (see6) and in the publications listed in the bibliography (see7). 2.2.2 Noise generator 2.2.2.1 Output characteristics The r.m.s.
49、 voltage of the noise source, when measured in a bandwidth of about2 kHz, shall not vary by more than 0,5dB within the bandwidth corresponding to the baseband of the system under test. The test signal should have a Gaussian amplitude distribution up to a peak-to-r.m.s. ratio of at least12dB. The density of the noise power at the generator output shall have a maximum value of not less than 40 dBm/kHz to enable loading levels up to at least 10 dB above the conventional loading level to be used. The tran