1、BRITISH STANDARD BS EN 61603-3:1998 IEC 61603-3:1997 Transmission of audio and/or video and related signals using infra-red radiation Part 3: Transmission systems for audio signals for conference and similar systems The European Standard EN 61603-3:1998 has the status of a British Standard ICS 33.16
2、0.99BSEN61603-3:1998 This British Standard, having been prepared under the directionof the Electrotechnical Sector Board, was published underthe authority of the Standards Board and comes into effect on 15 May 1998 BSI 04-1999 ISBN 0 580 29285 1 Amendments issued since publication Amd. No. Date Comm
3、entsBSEN61603-3:1998 BSI 04-1999 i Contents Page National foreword ii Foreword 2 Text of EN 61603-3 3BSEN61603-3:1998 ii BSI 04-1999 National foreword This British Standard is the English language version of EN 61603-3:1998. It is identical with IEC61603-3:1997. It supersedes Chapter 2 of BS6418:198
4、3 which has been withdrawn. The UK participation in its preparation was entrusted by Technical Committee EPL/100, Audio, video and multimedia systems and equipment, to Subcommittee EPL/100/3, Equipment and systems in the field of audio, video and audiovisual engineering, which has the responsibility
5、 to: aid enquirers to understand the text; present to the responsible international/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 UK. IEC 61603 co
6、mprises the following parts: Part 1: General (1997); Part 2: Transmission systems for audio wide band and related signals(1997); Part 3: Transmission systems for audio signals for conference and similar systems; Part 4: Transmission systems for low speed remote control; Part 5: Transmission systems
7、for high speed data and remote control; Part 6: Transmission systems for video and audiovisual signals of high quality. A list of organizations represented on this subcommittee can be obtained on request to its secretary. From 1 January 1997, all IEC publications have the number 60000 added to the o
8、ld number. For instance, IEC 27-1 has been renumbered as IEC60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally inc
9、lude an annex which lists normative references to international publications with their corresponding European publications. The British Standards which implement these international or European publications may be found in the BSI Standards Catalogue under the section entitled “International Standa
10、rds 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 with a British Standar
11、d does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, page i and ii, theENtitle page, pages 2 to 10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amend
12、ments incorporated. This will be indicated in the amendment table on theinside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN61603-3 February1998 ICS33.160.99 Supersedes HD455 S1:1985 Descriptors: Sound transmission, electroacoustic equipment, infrared radiation, specifications, me
13、asurements, characteristics, performance evaluation, electromagnetic compatibility, marking English version Transmission of audio and/or video and related signals using infra-red radiation Part 3: Transmission systems for audio signals for conference and similar systems (IEC 61603-3:1997) Transmissi
14、on de signaux audio et/ou vido et de signaux similaires au moyen durayonnement infrarouge Partie3:Transmission audio pour systmes de confrence et systmes similaires (CEI 61603-3:1997) bertragung von Ton- und/oder Bildsignalen und verwandten Signalen mitInfrarot-Strahlung Teil 3: bertragungssysteme f
15、r Audiosignalefr Konferenzsysteme undhnliches (IEC 61603-3:1997) This European Standard was approved by CENELEC on 1998-01-01. 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 stand
16、ard without any alteration. Up-to-date 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 othe
17、r 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 official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland,
18、France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, 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
19、 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. Ref. No. EN61603-3:1998 EEN61603-3:1998 BSI 04-1999 2 Foreword The text of document 100C/129/FDIS, future edition1 of IEC 61603-3, pr
20、epared by SC 100C, Audio, video and multimedia subsystems and equipment, of IEC TC 100C Audio, video and multimedia systems and equipment, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN61603-3 on 1998-01-01. This European Standard supersedes chapter 2 of HD 455 S1:1
21、985. This standard is to be used in conjunction with ENV50185-1:1995. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. In this standard, Annex ZA is normative. Annex ZA has been added by CENELEC. Endorsement notice The text of the International Sta
22、ndard IEC 61603-3:1997 was approved by CENELEC as a European Standard without any modification. Contents Page Foreword 2 1 General 3 1.1 Scope 3 1.2 Normative references 3 1.3 Definitions 3 2 Explanation of terms and general information 3 3 System considerations 5 3.1 Application area 5 3.2 Environm
23、ent 5 3.3 System planning and installation 5 3.4 Partition of functions between elements of the system 5 Page 4 General conditions for measurements 5 5 Characteristics to be specified and their methods of measurement 5 5.1 Characteristics of the IR source 5 5.2 Characteristics of the receiver 6 6 In
24、terface (matching) values, performance requirements and recommendations 6 6.1 Interface values for transmitter output signals 6 6.2 Interface values for radiator input signals 7 6.3 Polarity 7 6.4 Spurious emissions and signals 7 6.5 Sensitivity to random incidence 8 6.6 Rated signal-to-noise ratio
25、8 6.7 Channel allocation and modulation characteristics 8 6.8 Interface values for audio signals 8 6.9 Overall audio frequency performance requirements 8 7 Marking and contents of specifications 9 7.1 Marking 9 7.2 Contents of specifications 9 Annex ZA Normative reference to international publicatio
26、ns with their corresponding Europeanpublications Inside back cover Figure 1 Schematic representation of a conference sound system 10 Figure 2 Signal chain and related IEC standards 10 Figure 3 Allocation of channels and recommended carriers L 10 Table 1 Channel code, identification number and subcar
27、rier frequency 8 Table 2 Marking and contents of specifications 9 latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 1998-10-01 latest date by which the national standards conflicting with the EN have to be wit
28、hdrawn (dow) 1998-10-01EN61603-3:1998 BSI 04-1999 3 1 General 1.1 Scope This part of IEC 61603 gives methods for measuring and specifying those characteristics of audio infra-red (IR) transmission systems for conference and similar systems which are not covered by part 1 (see also 3.1). It allows sy
29、stems which make different economic use of the available bandwidth to be described in order that conclusions regarding interference and compatibility can be drawn. Interface (matching) values and other system characteristics are also covered. The standard replaces chapter 2 of IEC60764. 1.2 Normativ
30、e references The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of IEC 61603. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on
31、 this part of IEC61603 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. IEC 60068, Environmental testing. IEC 60268-15:1996, Sound syste
32、m equipment Part 15: Preferred matching values for the interconnection of sound system components. IEC 60315-4:1982, Methods of measurement on radio receivers for various classes of emission Part 4: Radio-frequency measurements on receivers for frequency modulated sound-broadcasting emissions. IEC 6
33、0417:1973, Graphical symbols for use on equipment Index, survey and compilation of the singlesheets. IEC 60764:1983, Sound transmission using infra-red radiation. IEC 60914:1988, Conference systems Electrical and audio requirements. IEC 61147:1993, Uses of infra-red transmission and the prevention o
34、r control of interference between systems. IEC 61603-1:1997, Transmission of audio and/or video and related signals using infra-red radiation Part 1: General. IEC 61938:1996, Audio, video and audiovisual systems Interconnections and matching values Preferred matching values of analogue signals. ISO
35、7000:1989, Graphical symbols for use on equipment Index and synopsis. ITU-R 412-6:1995, Planning standards for FM sound broadcasting at VHF. ITU-R 641:1990, Determination of radio-frequency protection ratios for frequency-modulated sound broadcasting. ITU-R 704:1990, Characteristics of FM sound broa
36、dcasting reference receivers for planning purposes. 1.3 Definitions For the purpose of this part of IEC 61603, the definitions given in part 1 apply. 2 Explanation of terms and general information 2.1 Transmitter A transmitter (link A-B in Figure 2) has an audio signal input (analogue or digital), a
37、nd a special form of electrical output to feed a radiator. 2.2 Combined transmitter and radiator A combined transmitter and radiator (link A-C in Figure 2) does not have an electrical output, and interface values therefore apply only at the input.EN61603-3:1998 4 BSI 04-1999 2.3 Radiator A radiator
38、(link B-C in Figure 2) has a special form of electrical input, to be fed by a transmitter. A radiator may be combined with other functions, such as a transmitter. At present, radiators normally consist of a number (from ten and more) of infra-red emitting diodes (IREDs) employing different technolog
39、ies. These devices have peak emissions in the wavelength range830nm to950nm, and an IR bandwidth of about100nm. 2.4 Receiver Besides the general characteristics given in part 1 and shown as link C-D in Figure 2, others may need to be specified if a receiver is combined with other units to serve, for
40、 example, as a transmitter for up-stream signals in a duplex system. To eliminate interference from other modulated IR sources, the receiver shall provide enough selectivity with regard to the modulated subcarrier in addition to selectivity in the IR band. Normally, this selectivity shall correspond
41、 to the spectral bandwidth of the modulated subcarrier signal, with some margin for instabilities and possible extra features. Definitions and methods of measurement for selectivity in relation to analogue FM signals are given in the standards dealing with FM broadcast systems, such as IEC60315-4 an
42、d ITU-R412, ITU-R 641 andITU-R704. NOTEFor digital audio transmission, the subject of receiver selectivity is under consideration. 2.5 Ancillary equipment Ancillary equipment, such as power supplies or battery chargers, may be required for the operation of the system. The manufacturer should specify
43、 all the data necessary for correct operation and maintenance. 2.6 Transmission of audio signals 2.6.1 Analogue audio signals Due to its technical performance and bandwidth economy, frequency modulation multiplex is mainly used for multichannel operation and is, at present, the only technique for wh
44、ich compatible equipment is available from different manufacturers. With this modulation technique, the transmitter output signal consists of a group of modulated subcarriers; this frequency-division multiplex makes economic use of the available bandwidth. Pulse modulation may be used for the transm
45、ission of analogue signals, usually employing pulses whose duration is less than14s. This technique requires a wide transmission channel, but allows the use of very low average IR power. At present, equipment supplied by different manufacturers is seldom compatible. The types of modulation in use in
46、clude differential pulse position modulation (where the timing of a pulse is determined relative to that of the preceding pulse, so that a floating time raster is employed), pulse frequency modulation with variable carrier frequency, and pulse amplitude modulation (providing six modulation channels)
47、. In general, present pulse modulation systems provide fewer channels usable in the same space than FM systems can provide. 2.6.2 Digital audio signals Under consideration. 2.7 Electromagnetic compatibility General information is given in part 1 of IEC 61603. Extensive information on inter-system in
48、terference and interference from other sources of IR is given in IEC61147. For electromagnetic compatibility, reference is made to the IEC generic standards being prepared by CISPR and IECTC77. 2.8 Safety aspects Safety is dealt with in part 1 of IEC 61603. It should be noted that systems within the
49、 scope of this part use radiators which give a high concentration of IR power at short distances, but the spatial average power is low.EN61603-3:1998 BSI 04-1999 5 2.9 Future developments in modulation techniques While systems using frequency modulation and systems using several different forms of pulse modulation are available, other techniques are under development, at a stage too early for standardization. Care is required to ensure that new systems do not cause further difficulties with band-sharing and inter
