BS EN 60835-2-10-1993 Methods of measurement for equipment used in digital microwave radio transmission systems - Measurements on terrestrial radio-relay systems - Overall system p.pdf

1、BRITISH STANDARD BS EN 60835-2-10: 1993 BS7573-2.10: 1993 IEC835-2-10: 1992 Methods of measurement for equipment used in digital microwave radio transmission systems Part2: Measurements on terrestrial radio-relay systems Section2.10 Overall system performance The European Standard EN60835-2-10:1993

2、has the status of a BritishStandard UDC621.396.7:621.317.083BSEN 60835-2-10:1993 This BritishStandard, having been prepared under the directionof the Electronic Equipment Standards Policy Committee, was published underthe authority oftheStandards Board and comes intoeffect on 15June 1993 BSI01-2000

3、The following BSI references relate to the work on this standard: Committee reference EEL/25 Draft for comment 91/29838 DC ISBN 0 580 21854 6 Cooperating organizations The European Committee for Electrotechnical Standardization (CENELEC), under whose supervision this European Standard was prepared,

4、comprises the national committees of the following countries: Austria Italy Belgium Luxembourg Denmark Netherlands Finland Norway France Portugal Germany Spain Greece Sweden Iceland Switzerland Ireland United Kingdom Amendments issued since publication Amd. No. Date CommentsBSEN 60835-2-10:1993 BSI

5、01-2000 i Contents Page Cooperating organizations Inside front cover National foreword ii Foreword 2 Introduction 3 1 Scope 3 2 Normative references 3 3 Bit-error ratio (BER) 3 4 Jitter 5 5 Acceptable input interruption 5 6 Verification of protection switching operation 5 Annex ZA (normative) Other

6、international publications quoted in this standard with the references of the relevant European publications 8 National annex NA (informative) Committees responsible Inside back cover National annex NB (informative) Cross-reference Inside back cover Figure 1 Illustration of interference sources in t

7、hree-channel radio-relay system 6 Figure 2 Presentation of carrier-to-noise ratio degradation by two bit-error ratio (BER) functions 6 Figure 3 Effect of co-channel interference and adjacent-channel interference 7BSEN 60835-2-10:1993 ii BSI 01-2000 National foreword This BritishStandard has been pre

8、pared under the direction of the Electronic Equipment Standards Policy Committee and is the English language version of EN60835-2-10:1993 Methods of measurement for equipment used in digital microwave radio transmission systems Part2: Measurements on terrestrial radio-relay systems: Section10 Overal

9、l system performance, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC835-2-10:1992 published by the International Electrotechnical Commission (IEC). BS EN60835 is published in three Parts. The other Parts are: Part1: Measurements common to

10、 terrestrial radio-relay systems and satellite earth stations; Part3: Measurements on satellite earth stations. Some of the many Sections of the three Parts have appeared under the number BS7573, of the same generic title. Copies of International Radio Consultative Committee (CCIR) documents may be

11、purchased through BSI Sales, Linford Wood, Milton Keynes, MK146LE. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunit

12、y from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, the EN title page, pages2 to8, 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 indi

13、cated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN60835-2-10 January1993 UDC621.396.7:621.317.083 Descriptors: Radiocommunications, radio equipment, microwave frequencies, digital transmission, radio-relay systems, measurement English version

14、Methods of measurement for equipment used in digital microwave radio transmission systems Part2: Measurements on terrestrial radio-relay systems Sectionten Overall system performance (IEC835-2-10:1992) Mthodes de mesure applicables au matriel utilis pour les systmes de transmission numrique en hyper

15、frquence Partie2: Mesures applicables aux faisceaux hertziens terrestres Section dix Performance globale du systme (CEI835-2-10:1992) Meverfahren fr Gerte in digitalen Mikrowellen-Funkbertragungssystemen Teil2: Messungen an terrestrischen Richtfunksystemen Hauptabschnitt zehn Leistungsdaten des Gesa

16、mtsystems (IEC835-2-10:1992) This European Standard was approved by CENELEC on1992-06-16. 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-dat

17、e 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 (English, French, German). A version in any other language made by translation under

18、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 Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Lux

19、embourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brus

20、sels 1993 Copyright reserved to CENELEC members Ref.No.EN60835-2-10:1993EEN 60835-2-10:1993 BSI 01-2000 2 Foreword The text of document12E(C0)145, as prepared by sub-committee12E, Radio relay and fixed satellite communications systems, of IEC technical committee12, Radiocommunications, was submitted

21、 to the IEC-CENELEC parallel vote in August1991. The reference document was approved by CENELEC as EN60835-2-10 on16 June1992. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. In this standard, Annex ZA is normative. latest date of publication ofan

22、 identical national standard (dop)1993-12-01 latest date of withdrawal ofconflicting national standards (dow)1993-12-01EN 60835-2-10:1993 BSI 01-2000 3 Introduction In previous sections of IEC835-2 measurement methods for parameters of the digital radio-relay system have been discussed separately fo

23、r each part of the system. In addition to these tests, the overall performance of a complete simulated system should be tested. The tests cover the two basic parameters of digital transmission systems, bit-error ratio and jitter, as well as the acceptable input interruption and verification of the p

24、rotection switching operation, which are all affected by the presence of more than one radio channel and/or radio hop. The measurement of other additional parameters such as error-free seconds, burst-error ratio, block-error ratio, which remain under consideration by other international organization

25、s, may also be required. 1 Scope This section IEC835-2 deals with measurements to be carried out during factory acceptance tests and type approval tests on a complete simulated digital radio-relay system, following tests on the individual parts of the system. In the following, it will be stated for

26、each parameter whether or not a multi-hop measurement is required in the overall system performance test, depending on the cumulative or non-cumulative property of that parameter. In this section, the emphasis is on the system configuration. For methods of measurement, see under the appropriate futu

27、re sections of IEC835-1 and IEC835-2. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this section of IEC835-2. At the time of publication, the editions indicated were valid. All standards are subject to revision, and

28、parties to agreements based on this section of IEC835-2 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. IEC835-1-4:1992, Methods of measurement f

29、or equipment used in digital microwave radio transmission systems Part1: Measurements common to terrestrial radio-relay systems and satellite earth stations Section4: Transmission performance. IEC835-2-4, Methods of measurement for equipment used in digital microwave radio transmission systems Part2

30、: Measurements on terrestrial radio-relay systems Section4: Transmitter/receiver including modulator/demodulator. (In preparation) IEC835-2-6, Methods of measurement for equipment used in digital microwave radio transmission systems Part2: Measurements on terrestrial radio-relay systems Section6: Pr

31、otective switching. (Under consideration) IEC835-2-8, Methods of measurement for equipment used in digital microwave radio transmission systems Part2: Measurements on terrestrial radio-relay systems Section8: Adaptive equaliser. (In preparation) CCIR Report930-2, Performance objectives for digital r

32、adio-relay systems Recommendations and reports of the CCIR, 1990, Annex to VolumeIX Part1. 3 Bit-error ratio (BER) The method of measurement is given in IEC835-1-4. The configuration of the transmit-receive section during the measurement is discussed in the future IEC835-2-4. As explained in IEC835-

33、2-4, the bit-error ratio of a transmit-receive section has a receiver input level dependent part and a constant part covering the nominal receiver input level. These two parts should be distinguished in overall system performance tests. In addition to single-hop measurements over individual channels

34、, the bit-error ratio degradation due to multi-channel and multi-hop transmission should also be measured where applicable. 3.1 Bit-error ratio versus receiver input level In a multi-hop link, this test is carried out separately for each hop for every radio channel, including tests with greater than

35、 nominal receiver input levels to cover up-fade conditions. There is no need for the measurement of the complete multi-hop link as there is no degradation due to multi-hop transmission (assuming that reduced receiver input level due to flat fading is present only in a single hop at a time).EN 60835-

36、2-10:1993 4 BSI 01-2000 3.2 Residual bit-error ratio at nominal receiver input level This is the low bit-error ratio which is due to low-level residual noise sources and equipment degradation, including ageing, in the transmit-receive equipment of each hop (see CCIRReport930-2). The contribution of

37、each hop is cumulative so it is measured for the complete multi-hop link in all radio channels. The definition and method of measurement of the residual bit-error ratio is described in IEC835-1-4. 3.3 Bit-error ratio degradation due to multi-channel interference 3.3.1 Definition and general consider

38、ation Multi-channel interference is one of the important parameters of multi-channel microwave transmission systems as it is closely related to efficient spectrum utilization. It is mainly determined by the radio-frequency channel arrangement, the frequency response of the individual radio channels,

39、 the cross-polarization discrimination of the antenna system and the transmission medium during fading conditions, by multipath propagation. Multi-channel interference sources are illustrated in Figure 1, showing two kinds of interference. a) Adjacent-channel interference, originating from neighbour

40、ing channels, generated by the unwanted reception of signals transmitted either in the same direction by neighbouring stations (far-end interference) or in the opposite direction by the same station (near-end interference). The former is due to insufficient selectivity of the channel filters whilst

41、the latter is mainly caused by insufficient de-coupling between transmitter and receiver (e.g.in the circulator and/or polarizer). b) Co-channel interference, originating from the same channel, generated either by the unwanted reception of signals transmitted by neighbouring stations via rearwards a

42、ntenna radiation in the opposite direction, or by the unwanted reception of cross-polarized signals due to finite cross-polarization discrimination. All types of multi-channel interference result in the degradation of the bit-error ratio. Such degradation can also be related to the carrier-to-noise

43、ratio. It can be quantified by the difference in decibels between the r.f. carrier levels at the receiver input, measured with and without interfering channels, that result in the same specified bit-error ratio. 3.3.2 Method of measurement The carrier-to-noise ratio degradation of a radio channel in

44、 a multi-channel transmission system is measured on a single transmit-receive section, as explained in IEC835-2-4, with all radio channels working under operational conditions. The radio channel under test is connected to a bit-error ratio measuring instrument as explained in IEC835-1-4. The digital

45、 inputs of all interfering channels are driven by independent (uncorrelated) pseudo-random bit sequence (p.r.b.s.) generators. All interfering channels are first switched off, and the r.f. input level of the test channel is adjusted for a specified bit-error ratio (e.g.10 5 ). The interfering channe

46、ls are then switched on, resulting in an increase of the test channel bit-error ratio. The test channel r.f. input level is subsequently increased until the above specified bit-error ratio is restored, and the difference in decibels between the two carrier levels is noted. 3.3.3 Presentation of resu

47、lts Results are presented by stating the value in decibels of the carrier-to-noise ratio degradation pertaining to a specified bit-error ratio. Alternatively, two curves may be presented, with and without interference, both showing the bit-error ratio as a function of the carrier-to-noise ratio (see

48、Figure 2). 3.3.4 Details to be specified The following items should be included, as required, in the detailed equipment specification: a) carrier frequencies and polarizations of the test channel and the interfering channels; b) bit-error ratio at which the carrier-to-noise ratio degradation due to

49、interference is measured; c) r.f. input level of the test channel without interference at the above bit-error ratio, in dBm; d) r.f. input levels of interfering channels, in dBm; e) highest permitted carrier-to-noise ratio degradation, in dB. NOTEAn alternative method to assess the effect of multi-channel interference is to plot the test channel receiver input level required for a specified bit-error ratio (e.g.10 3 ) as a function of the interfering channel receiver input level. By plotting two curves, one for co-channel interfer