1、 STDmETSI EN 301 222-ENGL 1494 M 3400855 D4ZL002 T7L M ETSI EN 301 222 1.1.1 (1999-07) European Standard fletemrnrnunktions seties) Digital Video Broadcasting (DVB); Co-ordination channels associated with Digital Satellite News Gathering (DSNG) STDmETSI EN 303 222-ENGL 3977 = 3400855 0423003 906 ETS
2、I EN 301 222 V1.l.l (1999-07) 2 Reference DEWJTC-DVB-82 (bbcOOico.PDF) Keywords DVB, digital, video, broadcasting, SNG, TV Postal address F-06921 Sophia Antipolis Cedex - FRANCE Office address 650 Route des Lucioles - Sophia Antipolis Valbonne - FRANCE Tel.: +33 4 92 94 42 O0 Fax: +334 93 65 47 16 A
3、ssociation but non lucratif enregistre la Sous-PrBfecture de Grasse (Os) No 7803/88 Cid W 348 623 562 00017 - NAF 742 C Internet secretariat et$i.fr Individual copies of this ETSI deliverable can be downloaded from http:/www.etsi.org If you find errors in the present document, send your comment to:
4、editoretsi.fr Copyrfgbt Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in ail media. Q European Telecommunications Standards Institute 1999. 8 European Broadcasting Union 1999. Ail rights reserved.
5、 3 ETSI EN 301 222 V1.l.l (199947) Contents Intellectual Property Rights . 4 Foreword 4 1 2 3 3.1 3.2 4 5 5.1 5.2 5.3 6 7 7.1 7.2 7.3 7.4 scope 5 References . 8 Symbols and abbreviations 8 Symbols . 8 Abbreviations . 9 System definition . 10 Source coding and interfaces . 11 Voice coding 11 Data cod
6、ing (Optional) 11 Signalling . 12 Multiplexing and interfaces . 12 Transmission system and interfaces 13 Randomization for energy dispersal . 13 Inner coding (convolutional) 14 Spread Spectnim 15 Bit mapping, baseband shaping and modulation 17 7.4.1 7.4.2 8 Annex A (normative): Annex B (normative):
7、Annex C (normative): Bit mapping to QPSK constellation . 17 Baseband shaping and quadrature modulation . 18 Error performance requirements 18 Signal spectrum at the modulator output 19 Transmission setups 21 Implementation of “optional“ features . 22 Annex D (informative): Examples of possible use o
8、f the System . 23 Bibliography 28 History 29 STD-ETSI EN 301 222-ENGL 1997 3400855 0421005 780 6 4 ETSI EN 301 222 V1.l.l (1999-07) Intellectual Property Rights PRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to these essentia
9、l PRs, if any, is publicly available for ETSI members and non-members, and can be found in SR o00 314: “Intellectual Property Rights (IPRs); Essential, orpotentially Essential, IPRs notified to ETSI in respect of ETSI standards“, which is available free of charge from the ETSI Secretariat. Latest up
10、dates are available on the ETSI Web server (http:llwww.etsi.org/ipr). Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee can be given as to the existence of other IPRs not referenced in SR O00 314 (or the updates on the ETSI Web serv
11、er) which are, or may be, or may become, essential to the present document. Foreword This European Standard (Telecommunications series) has been produced by the Joint Technical Committee (JTC) Broadcast of the European Broadcasting Union (EBU), Comit Europen de Normalisation ELECtrotechnique (CENELE
12、C) and the European Telecommunications Standards Institute (ETST). NOTE. The EBU/ETSI JTC Broadcast was established in 1990 to co-ordinate the drafting of standards in the specific field of broadcasting and related fields. Since 1995 the JTC Broadcast became a tripartite body by including in the Mem
13、orandum of Understanding also CENELEC, which is responsible for the standardization of radio and television receivers. The EBU is a professional association of broadcasting organizations whose work includes the co-ordination of its members activities in the technical, legal, programme-making and pro
14、gramme-exchange domains. The EBU has active members in about 60 countnes in the European broadcasting area; its headquarters is in Geneva. European Broadcasting Union CH-1218 GRAND SACONNEX (Geneva) Switzerland Tel: 41 22 71 7 21 11 Fax: +41 22 71 7 24 81 Digital Video Broadcasting VB) Project Found
15、ed in September 1993, the DVB Project is a market-led consortium of public and private sector organizations in the television industry. Its aim is to establish the framework for the introduction of MPEG-2 based digital television services. Now comprising over 200 organizations from more than 25 coun
16、tries around the world, DVB fosters market-led systems, which meet the real needs, and economic circumstances, of the consumer electronics and the broadcast industry. I National transposition dates I Date of adoption of this EN: Date of latest announcement of this EN (doa): 18 June 1999 30 September
17、 1999 Date of latest publication of new National Standard or endorsement of this EN (dople): 31 March 2000 Date of withdrawal of any conflicting National Standard (dow): 31 March 2000 5 ETSI EN 301 222 Vl.l.l (199407) 1 Scope According to -R Recommendation SNG.770-1, Satellite News Gathering (SNG) i
18、s defined as “Temporary and occasional transmission with short notice of television or sound for broadcasting purposes, using highly portable or transportable uplink earth stations . . .“. EN 301 210 2 describes the frame structure, channel coding and modulation system for Digital Satellite News gat
19、hering (DSNG). For SNG technical and/or programme co-ordination, and interruptible feed-back, -R Recommendation SNG.77 1-1 recommends “that SNG earth stations should be equipped to provide two-way satellite communication circuits which must be available prior to, during and after, the transmission o
20、f the vision and associated sound or sound programme signal. These circuits will provide communications between the SNG operator, the satellite operator and the broadcaster; that two or more duplex circuits should be provided, whenever possible within the same transponder as the programme vision and
21、 associated sound or sound programme signal“. The same Recommendation considers “that throughout the world, where news events take place, uniform technical and operational standards for communication should be established to ensure prompt activation of the SNG service“. The availability of co-ordina
22、tion (communication) circuits by satellite may be particularly useful in areas where access to the public switched or cellular telephone networks is difficult or impossible. For these purposes, the same antennas of the DSNG stations may often be used, and the same frequency resources (or at least th
23、e same satellite transponder) as the main DSNG signal may be exploited. Other frequency resources may also be chosen according to the operational conditions and requirements. To achieve a two-way (Le. full-duplex) communication channel, two independent carriers have to be transmitted, one from the D
24、SNG terminal. the other from a fixed station. Depending on the service requirements, vanous scenarios are possible, some of which require reduced communication capacity, others are more demanding (in terms of the number of required connections and up-link facilities). Figure 1 shows two examples of
25、implementation of the co-ordination channels between the DSNG terminal, the broadcaster, the DSNG operator (when required) and the satellite operator: Scenario A (two up-links for Co-ordination carriers): the DSNG terminal and a central station (e.g. the broadcasters fixed station) uplink a single C
26、o-ordination carrier each, containing U multiplexed circuits. in this scenario, the terrestrial infrastructure (e.g. PSTN) is used to forward the co-ordination circuits from the centrai station to the DSNG operator and the satellite operator and the co-ordination equipment at the DSNG terminal has t
27、o transmit and receive a single co-ordination carrier. Scenario B (four up-links for co-ordination carriers): the DSNG terminal uplinks a single Co-ordination carrier, containing three multiplexed channels (U=3), while the broadcaster, the DSNG operator and the satellite operator up-link a total of
28、three Co-ordination carriers, each with a single circuit. in this scenario, the Co-ordination equipment at the DSNG terminal has to transmit a single co-ordination carrier, and to receive three carriers at the same time. STD-ETSI EN 303 222-ENGL 3999 H 3400855 0423007 553 6 SATELLiTE 1 CQORDINATION
29、SIGNALS v y ETSI EN 301 222 V1.l.l (lsssO7) SATELLrrE OPERATOR DSNG OPERATOR DsNGTeRMINAL BROADCASTER SCENARIO A with two uplinks DsNGTeRMML BROADCArn SCENARIO B with four uplinks Figure 1 : Example environments for DSNG and co-ordination transmissions by satellite The present document describes the
30、 source coding (for voice and data), multiplexing, channel coding and modulation system (denoted as the “System“ for the purposes of the present document) for the optional co-ordination (communication) channels by satellite associated with DSNG services. The integration of this System in a DSNG stat
31、ion shall be optional, since other communication systems (e.g. PSTN, cellular phones connected to terrestrial or satellite networks) may be used, according to the prevailing operational needs. Maximum compatibility with existing ETSI and ITU standards is maintained. In particular voice coding is per
32、formed according lTU-T Recommendation G.729 5 (see note), offering high voice quality at 8 kbitls (.e. better than ADPCM at 32 kbitls). Data transmission is performed in synchronous RS-422 format, at bit-rates of 8, 16, or 32 kbitls. Optionally it may be performed in asynchronous RS-232 7 format at
33、a maximum bit-rate of 9,6; 19,2 or 38,4 kbit/s. The System defined in the present document provides up to four full-duplex coordination (voice) channels at 8 kbitls by satellite, or data capacity for other applications. A Co-ordination channel may also convey FAXes. A fixed time-division multiplex a
34、llows the transmission of one, two or four 8 kbitls channels producing an output bit-stream at 8,16 kbit/s, 2 x 8,16 kbitls, 4 x 8.16 kbitls, respectively. The multiplex provides a signalling byte which indicates the multiplex configuration to the receiver. STD.ETSI EN 301 222-ENGL 1999 3400855 0423
35、008 4T m ETSI EN 301 222 V1.l.l (199947) 7 The system provides randomization for energy dispersal and inner convolutional coding (rate 1/2 only) for error correction, to achieve high ruggedness against noise and interference. Reed-Solomon coding and convolutional interleaving are not used in the Sys
36、tem, as the target BER ( lW3) after FEC decoding is adequate for voice communication using ITU-R Recommendation G.729 5, and additionally since they would generally introduce a large end-to-end delay which may cause problems on voice communications in DSNG applications. Direct-Sequence Spread-Spectr
37、um (DS-SS) processing is applied before Quaternary Phase Shift Keying (QPSK) modulation, generating a modulated signal whose bandwidth occupation is expanded and whose power spectral density level is reduced accordingly. DS-SS technique permits the superposition of a number of co-ordination signals
38、in the frequency domain (Code Division Multiple Access, CDMA), using the same centre frequency. For example the scenarios in Figure 1 may be efficiently implemented by using this technique. For system simplicity, the spreading processes are asynchronous at each tenninal, therefore the number of chan
39、nels which may be superimposed is limited by mutual interference. Compared to conventional modulations, DS-SS techniques offer significant performance improvements in the presence of interferences (e.g. from and to Co-channel narrow-band signals) and also produce less intermodulation noise density o
40、ver a non linear transponder. DS-SS signals also requk less frequency precision in the transmissiodreception equipment. The Co-ordination carriers may be transmitted at a power levei significantly lower than that of the DSNG carrier, since their bit-rate is typically some hundred times lower than th
41、e DSNG bit-rate, therefore they do not significantly modify the transponder operating point. Flexible. user-definable frequency assignments may be used for the co-ordination channels, allowing the selection on a case-by-case basis of the best frequency division multiplex (FDM) configuration in the s
42、atellite transponder. For example, the System is capable of operating, if required, within the same frequency slot as the main DSNG signal. while keeping the level of mutual interference between the main DSNG signal and the co-ordination carriers at an acceptable level (see Annex D for further detai
43、ls). To achieve this, the Co-ordination channels may be superimposed onto the main DSNG signal (e.g. same centre frequency), at the cost of some performance degradation due to mutual interference, which may be more or less critical depending on the modulatiodcoding scheme of the DSNG system and on t
44、he mutual signal levels. As an alternative, the Co-ordination channels using a low spreading factor (e.g. 0.5 MHz or 1 MHz bandwidth occupation) may be allocated within the “roll-off“ region of the DSNG signal, in order to reduce the mutual interference between co-ordination and DSNG signals. In oth
45、er cases, a clear hquency slot may be allocated to co- ordination channels, on the me transponder as the DSNG signal, or even on another transponder/satellite, according to the service requirements. The transmission parameters, such as the frequency, the symbol-rate and the spreading sequences are t
46、o be manually set- up in the co-ordination terminals; user definable configurations may be defined to simplify the link set-up (see Annex B). The present document: - - gives a general description of the System; specifies source coding, multiplexing, channel coding and modulation of the signal, in or
47、der to allow compatibility between equipments developed by different manufacturers. This is achieved by describing in detail the signal processing principles at the transmitting side, while the processing at the receive side is left open to different implementation solutions. However, it is necessar
48、y in the present document to refer to certain aspects of reception; identifies the global performance requirements and features of the System, in order to meet the service quality targets. - NOTE. The adoption of Annex A of -T Recommendation G.729 5 is under evaluation. Comments are invited during t
49、he ETSI Public Enquiry. STDmETSI EN 303 222-ENGL 1999 m 3400855 0423009 326 111 8 ETSI EN 301 222V1.1.1 (199947) 2 Ref e re nces The following documents contain provisions which, through reference in this text, constitute provisions of the present document. References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. For a specific reference, subsequent revisions do not apply. For a non-specific reference, the latest version applies. A non-specific reference to an ETS shall also be taken
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