《BS-EN-50083-10-1999.pdf》由会员分享，可在线阅读，更多相关《BS-EN-50083-10-1999.pdf（30页珍藏版）》请在三一文库上搜索。
1、BRITISH STANDARD BS EN 50083-10:1999 Cable networks for television signals, sound signals and interactive services Part 10: System performance for return paths The European Standard EN 50083-10:1999 has the status of a British Standard ICS 33.060.40 Licensed Copy: sheffieldun sheffieldun, na, Mon No
2、v 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 50083-10:1999 This British Standard, having been prepared under the direction of the Electrotechnical Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 December 1999 BSI 04-2000 IS
3、BN 0 580 35217 X National foreword This British Standard is the English language version of EN 50083-10:1999. The UK participation in its preparation was entrusted by Technical Committee EPL/100, Audio, video and multimedia systems and equipment, to Subcommittee EPL/100/4, Cabled distribution system
4、s, which has the responsibility to: aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the
5、 UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled
6、 “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. 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
7、with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages 2 to 24 and a back cover. This standard has been updated (see copyright date) and may have had am
8、endments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 50083-10:1999 BSI 04-2000i Content
9、s Page National forewordInside front cover Foreword2 Text of EN 50083-105 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ii blank Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUR
10、OPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 50083-10 March 1999 ICS 33.060.40 English version Cable networks for television signals, sound signals and interactive services Part 10: System performance for return paths Rseaux de distribution par cbles pour signaux de tlvision, signaux de radiodi
11、ffusion sonore et services interactifs Partie 10: Caractristiques des systmes de voie de retour Kabelnetze fr Fernsehsignale, Tonsignale und interaktive Dienste Teil 10: Rckkanal-Systemanforderungen This European Standard was approved by CENELEC on 1999-02-01. CENELEC members are bound to comply wit
12、h 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 Secretari
13、at 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 as the o
14、fficial versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee
15、 for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1998 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
16、 Ref. No. EN 50083-10:1998 E Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 50083-10:1999 BSI 04-2000 2 Foreword This European Standard was prepared by the Technical Committee CENELEC TC 209, Cable networks for television signals, sound
17、signals and interactive services. The text of the draft was submitted to the Unique Acceptance Procedure and was approved by CENELEC as EN 50083-10 on 1999-02-01. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. Annexes designated “informative” are
18、 given for information only. In this standard, Annex B is normative and Annex A and Annex C are informative. Contents Page Foreword2 1Scope5 1.1General5 1.2Specific scope of this part 105 2Normative references6 3Terms, definitions, symbols and abbreviations6 3.1Terms and definitions6 3.2Symbols8 3.3
19、Abbreviations8 4Methods of measurement9 4.1Setup of the network9 4.2Measurement of signal level11 4.3Measurement of amplitude response12 4.4Measurement of signal to noise ratio (S/N)12 4.5Measurement of multiple interference13 4.6Measurement of impulse noise14 4.7Measurement of echo ratio15 4.8Measu
20、rement of group delay variation15 4.9Measurement of frequency error16 4.10 Measurement of Bit Error Rate (BER)16 5System performance requirements18 5.1Introduction18 5.2Analogue parameters influencing system performance19 5.3General requirements20 5.4Specific system performance requirements20 6Syste
21、m performance recommendations20 6.1Proposal for the use of the return path bandwidth20 Annex A (informative) System performance requirements for different modulation techniques22 Annex B (normative) Correction factors for noise22 Annex C (informative) Bibliography24 Figure 1 Reference points of an a
22、ctive return path system (example)5 Figure 2 Procedure for setup and adjustment of an upstream plant11 Figure 3 Arrangement of test equipment for measurement of echo ratio15 Figure 4 Test setup for frequency stability measurement16 latest date by which the EN has to be implemented at national level
23、by publication of an identical national standard or by endorsement(dop) 1999-09-01 latest date by which national standards conflicting with the EN have to be withdrawn(dow) 1999-09-01 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 50083-
24、10:1999 BSI 04-20003 Page Figure 5 Principle of BER measurement17 Figure 6 Upstream signals affecting downstream signals18 Figure 7 Downstream signals affecting upstream signals18 Figure 8 Upstream signals of service 1 affecting upstream signals of a different service (e.g. service 2)19 Figure 9 Ups
25、tream signals of a specific service (e.g. service 2) affecting upstream signals of the same service19 Figure 10 Identification of the most common sub-bands within the return path band with limited transmission quality21 Figure B.1 Noise correction factor (CF)dB versus measured level difference (D)dB
26、23 Table 1 Characterization criteria for downstream and upstream operations10 Table 2 Examples of the Nyquist bandwidth of digitally modulated carriers12 Table 3 System performance requirements using a reference signal according to ETS 300800 (QPSK Grade C)20 Table 4 Return path frequency ranges20 T
27、able 5 Reasons for quality reduction in sub-bands of the return path21 Table A.1 System performance requirements for different modulation techniques for BER = 10422 Table B.1 Noise correction factor23 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy,
28、(c) BSI 4 blank Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 50083-10:1999 BSI 04-20005 1 Scope 1.1 General Standards of EN 50083 series deal with cable networks for television signals, sound signals and interactive services including
29、equipment, systems and installations for headend-reception, processing and distribution of television and sound signals and their associated data signals and for processing, interfacing and transmitting all kinds of signals for interactive services using all applicable transmission media. All kinds
30、of networks like CATV-networks MATV-networks and SMATV-networks individual receiving networks and all kinds of equipment, systems and installations installed in such networks, are within this scope. The extent of these standardization work is from the antennas, special signal source inputs to the he
31、adend or other interface points to the network up to the system outlet or the terminal input, where no system outlet exists. The standardization of any user terminals (i.e. tuners, receivers, decoders, multimedia terminals etc.) as well as of any coaxial and optical cables and accessories therefore
32、is excluded. 1.2 Specific scope of this part 10 This standard is dealing with the transparent return path of cable networks operated in the frequency range between 5 MHz and 65 MHz or parts thereof. Higher frequencies may be used in fibre based networks. NOTEIn addition it is possible to use the fre
33、quency range from 0 to 5 MHz for return path transmissions, e.g. for NMS or other control, monitoring and signalling purposes. Applications below 5 MHz are not covered by this standard. An active return path carries typically only return signals. A passive return path can be used for both return and
34、 forward signals. This standard lays down the basic methods of measurement for signals typically used in the return path of cable networks in order to assess the performance of those signals and their performance limits. All requirements refer to the performance limits which shall be obtained betwee
35、n the reference points (Figure 1) of the return path system. One reference point is the network termination close to the subscriber. It is the last point where all forward and return signals are present and carried on the same cable. If no network termination point exists, the reference point is the
36、 system outlet. The other reference point is the input of the return signal receiver (or transceiver). At this point the transparent signal path ends and behind this point the signal is treated in a non-transparent way. The return signal receiver can be situated at the headend but can also be at the
37、 node of the coaxial cell or at any other point of the network. Figure 1 Reference points of an active return path system (example) Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 50083-10:1999 6 BSI 04-2000 In addition to the system perf
38、ormance requirements for the transparent return path, system performance recommendations were laid down in this standard e.g. for the overall frequency allocation, for the use of specific modulation techniques for different interactive multimedia services or for different sub-bands within the return
39、 path frequency range etc. Specific equipment installed in cable networks for the operation of such return paths is standardized in the relevant equipment standards, parts 3 to 6 of the EN 50083 series. Transmission systems are not within the scope of this standard. 2 Normative references This Europ
40、ean Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications
41、apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. 3 Terms, definitions, symbols and abbreviations 3.1 Terms and definitions 3.1.1 broadcast signal a signal comprising of video and/o
42、r audio and/or data content which is distributed to several receivers simultaneously 3.1.2 downstream direction direction of signal flow in a cable network from the headend or any other central point (node) of a cable network to the subscribers area 3.1.3 forward path (downstream) part of a cable ne
43、twork by which signals are distributed in the downstream direction from the headend or any other central point (node) of a cable network to the subscribers area 3.1.4 frequency error a quality of supply evaluated on the basis of the actual frequency of an electrical system compared to the nominal va
44、lue. Frequency error consists of initial error, short term and long term frequency stability 3.1.5 headend equipment which is connected between receiving antennas or other signal sources and the remainder of the cable network, to process the signals to be distributed NOTEThe headend may, for example
45、, comprise antenna amplifiers, frequency converters, combiners, separators and generators. EN 50083Cable networks for television signals, sound signals and interactive services EN 50083-1 + A1 1993 1997 Part 1: Safety requirements EN 50083-2 + A1 1995 1997 Part 2: Electromagnetic compatibility for e
46、quipment EN 50083-31998Part 3: Active wideband equipment for coaxial cable networks EN 50083-41998Part 4: Passive wideband equipment for coaxial cable networks EN 50083-5199XPart 5: Headend equipment EN 50083-61997Part 6: Optical equipment EN 50083-7199XPart 7: System performance EN 50083-81999Part
47、8: Electromagnetic compatibility for networks ETS 3008001998Digital Video Broadcasting (DVB); Interaction channel for Cable TV distribution systems (CATV) Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 06 08:15:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 50083-10:1999 BSI 04-20007 3.1.6 hy
48、brid fibre coaxial network (HFC) cable network which is comprised of optical equipment and cables and coaxial equipment and cables in different parts 3.1.7 impulse noise this noise is caused by electromagnetic interference into cable networks. Impulse noise is characterized by pulses with a duration
49、 of typically 40 dB at the demodulator input. If this is not possible, move the demodulator and the oscilloscope closer to the modulator and measure the network in two parts. The part closer to the head-end has typically less echoes and that part is tested only to verify that the contribution to the total system echo ratio is negligible. 4.7.4.2 With the equipment connected as shown in Figure 3 adjust the oscilloscope time-base speed to 100 ns/div. Adjust the vertical gain and position controls so th