1、= 3b24bb 0587323 b8O BRITISH STANDARD Methods of measurement for equipment used in digital microwave radio transmission systems Part 3. Measurements on satellite earth stations Section 3.13 VSAT systems The European Standard EN 60835-3-13 : 1996 has the status of a British Standard ICs 33.060.30 NO
2、COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW I BS EN 1997 BS 7573 : Section 3.13 : 1997 1996 60835-3-13 : IEC 835-3-13 : BS EN 60835-3-13 : 1997 Committees responsible for this British Standard The preparation of this British Standard was entrusted by Technical Committee EPW12
3、, Radio communication, to Subcommittee EPL/12/5, Radio communication systems, upon which the foliowing bodies were represented British Broadcasting Corporation British Radio and Electronic Equipment Manufacturers Association British Telecommunications plc ERA Technology Ltd. Institution of Electrica
4、l Engineers Radio, Electrical and Television Retailers Association Radiocommunications Agency This British Standard, having been prepared under the direction of the Electrotechnicai Sector Board, was published under the authority of the Standards Board and comes into effect on 15 February 1997 O BSI
5、 1997 Amendments issued since publication 1 Date Amd. No. I Text affected The following BSI references relate to the work on this standard Committee reference EPL/12/5 Draft for comment 95/210409 DC ISBN O 580 26930 2 -p D LbZqbb 57L25-pL53 BS EN 608353-13 1997 Contents Committees responsible Nation
6、al foreword page Inside front cover ii Foreword Text of EN 60835-3-13 2 3 OBSI 1997 i BS EN 608353-13 : 1997 National foreword This British Standard has been prepared by Subcommittee EPL/12/5 and is the English language version of EN 608353-13 : 1996 Methods of measurement for equipment used in digi
7、tal microwave radio transmission systems Part 3: Measurements on satellite earth stations: Section 3.13 VSATsystems, published by the European Committee for Electrotechnicai Standar-on (CENELEC). It is identical with IEC 8353-13 : 1996 published by the Intedonai Electrotechnicai Commission (IEC). BS
8、 EN 60835 is published in three Parts. The other Parts are: Part 1 Measurement common to terrestrid dio-relay systems and satellite earth statwns Part 2 Measurements on terrestrial dzO-reluy systems Some of the many Sections of the three Parts have appeared under the number BS 7573, of the same gene
9、ric title. This Section describes measurements for very small aperture terminals (VSA%) of data transmitlreceive type, both in the star network and in the point-to-point network. Measurements of the hub earth stations equipment are not covered Cross-references Publication referred to Corresponding B
10、ritish Standard BS EN 60835 Methods of measurement for equipment used in digital microwave mdw transmission systems EN 608351-2 : 1993 (lEC 8351-2 : 1992) Part 1 Measurements common to terrestrial radio-relay systems and saMite earth stations Section 1.2 : 1995 Basic chamtemstics EN 6083514 : 1995 (
11、IEC 83514 : 1992) Section 1.4 Transmission perfomncel) EN 608353-2 : 1996 (IEC 83.53-2 : 1994) Part 3 Measurements on sateUite earth stations Section 3.2 : 1996Antmm EN 608353-7 : 1995 (IEC 835-3-7 : 1995) EN 55022 : 19872) (CISPR 22 : 1985) Section 3.7 : 1996 Figure-of-merit of receiving system Lim
12、its and methods of measurement of radio disturbance chmtemstics of information technology equipment Compliance 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 titl
13、e page, pages 2 to 22, an inside back cover and back cover. in preparation. 2, EN 55022 : 1987 has been superseded by EN 55022 : 1995 with which the cited British Standard is identical. ii O BSI 1997 Lb2Libb 0587327 22b EUROPEAN STANDARD NORME EUROPEENNE EUROPISCHE NORM EN 60835-3-1 3 July 1996 ICs
14、33.060.30 DescriptOro: Tekoommunia.tionu. rdiocommunicatiom, cwmwnication oquipnwnt. earth station, microwwe froquoncios, digitil technics, measurements, characteristic8 English version Methods of measurement for equipment used in digital microwave radio transmission systems Part 3: Measurements on
15、satellite earth stations Section 13: VSAT systems (IEC 835-3-1 3:1996) Mthodes de mesure applicables au matriel utilis pour les systmes Meverfahren fr Gerte in digitalen Mikrowellen-Funk bertrag ungssystemen Satelliten-Erdfunkstellen - de transmission numrique en Teil 3: Messungen an - E hyperfrquen
16、ce E - Partie 3: Mesures applicables aux Hauptabschnitt 13: VSAT-Systeme - - stations terriennes de (IEC 835-3-1 3:1996) I _. tlcommunications par satellite I- I- Ln Section 13: Systmes VSAT (CE1 835-3-1 3:1996) This European Standard was approved by CENELEC on 1996-07-02. CENELEC members arebound t
17、o comply with the CENICENELEC 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 Centr
18、al 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 sta
19、tus 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
20、 Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: NO de Stassari 35, B - 1050 Brussels Ref. NO. EN 60835-3-13:1996 E W lb24bb 0587128 Lb2 Page 2 EN 60836-3-13 : 1996 Foreword The text of document 12
21、E/237/FDIS, future edition 1 of IEC 8353-13, prepared by SC 12E, Radio-relay and fixed satellite commmunication syskms, of IEC TC 12, Radiocommunications, was submitted to the IEGCENELEC parallel vote and was approved by CENELEC as EN 60835-3-13 on 1996-0742. The following dates were fixed: - latest
22、 date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 1997-04-01 latest date by which the national standards conflicting with the EN have to be withdrawn - (dow) 1997-0401 Annexes designated normative are part of the bo
23、dy of the stanhd. Annexes designated informative are given for information oniy. in this standard, annex ZA is normative and annex A is informative. Annex ZA has been added by CENELEC. Contents 1 1.1 1.2 2 3 3.1 3.2 3.3 3.4 3.6 3.6 Figures General Scope Normative references General description Metho
24、ds of measurement General considerations Antenna RF characteristics Moduiator/demodulator performance End-bend connection test Monitor and control Page 3 3 3 4 5 5 5 6 10 14 15 17 Annexes A (informative) Bibliography 20 ZA (nonnative) Normative references to international publications with their cor
25、responding European publications 21 O BSI 1997 m LbZqbbS 0587329 UT9 m Page 3 EN 60835-3-13 : 1996 * * u1 METHODS OF MEASUREMENT FOR EQUIPMENT USED IN DIGITAL MICROWAVE RADIO TRANSMISSION SYSTEMS - Part 3: Measurements on satellite earth stations - Section 13: VSAT systems 1 General 1.1 Scope This s
26、ection of IEC 835-3 deals with the methods of measurements applicable to very small aperture terminals (VSATs) of data transmitlreceive type both in the star network (many VSATs controlled by the hub earth station) and in the point-to-point network. Some clauses may also be applicable to the receive
27、-only type VSATs. This section does not handle the measurements of the hub earth stations equipment. 1.2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this section of IEC 835-3. At the time of publication, th
28、e editions indi- cated were valid. All normative documents are subject to revision, and parties to agreements based on this section of IEC 835-3 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and IS0 maint
29、ain registers of currently valid International Standards. IEC 835-1 -2: 1992, Methods of measurement for equipment used in digital microwave radio transmission systems - Part 7: Measurements common to terrestrial radio-relay systems and satellite earth stations - Section 2: Basic characteristics IEC
30、 835-1 -4: 1992, Methods of measurement for equipment used in digital microwave radio transmission systems - Part 1: Measurements common to terrestrial radio-relay systems and satellite earlh stations - Section 4: Transmission performance 835-3-2: 1995, Methods of measurement for equipment used in d
31、igital microwave radio transmission systems - Part 3: Measurements on satellite earth stations - Section 2: Antenna IEC 835-3-7: 1995, Methods of measurement for equipment used in digital microwave radio transmission systems - Part 3: Measurements on satellite earth stations - Section 7: Figure-of-m
32、erit of receiving system IEC CISPR 22: 1985, Limits and methods of measurement of radio interference charac- teristics of information technology equipment ITU-R Recommendation S 725: 1992. Technical characteristics for very small aperture terminals (VSATs) * Formerly CCIR. Page 4 EN 60835-3-13 1996
33、ITU-R Recommendation S 729: 1992, Control and monitoring function of vety small aperiure terminals (VSATs) ITU-T. Recommendation X 24: 1988, List of definitions for interchange circuits between data terminal equipment (DTE) and data cirwit-terminating equipment (DCE) on public data circuit-terminati
34、ng equipment (DCE) on public data networks ITU-T Recommendation X 25: 1993, Interface between data terminal equipment (DTE) and data circuit-terminating equipment (DCE) for terminals operating in the packet mode and connected to public data networks by dedicated circuit Radio Regulations, Appendix 8
35、: 1990, Table of maximum permitted spurious emission power levels 2 General descrlpt Ion VSATs are small, lowcost satellite earth stations which are equipped with small antennas (typically 1 m to 2 m), with low power RF transmitters (typically 0,s W to 2 W), and with compact modem and signal process
36、ing units. They can be installed very easily on roof tops, on a wall, or in the car park of the users office building, where the user data terminals are located. They can be used very conveniently and economically to connect the user terminals to the central host computer located at a distant proces
37、sing centre. The VSATs are usually used for digital data communications. However, H is possible to use them for voice and/or video communications by adding appropriate voice/video cader/decoders or by adding TV receivers to demodulate analog FM N signals. VSATs are often used in the star type networ
38、k as shown in figure la). VSATs com- municate with a relatively large central earth station, called the hub earth station. In this case, the type of modulation, the bit rates, the coding and access techniques of the outbound hub to VSAT) channel and the inbound (VSAT to hub) channel are usually diff
39、erent in order to use the satellite channels effectively by multiple access schemes. In this type of VSAT networks the user data are usually processed by the VSAT and hub to support the various computer network protocols effectively. Point-to-point connections between VSATs as shown in figure lb) ar
40、e also used. In this case, the modulation rate and format of the transmitting and receiving signals of the VSAT are usually the same, and the user data are usually passed through the VSAT network transparently without the protocol processing. Usually a network control and monitoring computer is prov
41、ided to control and monitor the network configuration and operation. Formerly CCIR. 1b24bb7 0587131 757 = Page 5 EN 60835-3-13 : 1996 * * m A typical configuration of a VSAT is shown in figure 2. It consists of an antenna, an outdoor unit (ODU) and an indoor unit (IDU). Offset parabolic type antenna
42、s are widely used and often the feed horn is integrated with the ODU, which contains a low noise amplifier, a high power amplifier and upldown converters in a weatherproof housing and installed behind the antenna focal point. The IDU contains an i.f. circuit, a modem and a baseband signal processor,
43、 and is installed near the user data terminals. The ODU and the IDU are connected by inter-facility link (IFL) cable). The ITU-R has established recommendations for technical characteristics of VSATs (see ITU-R Recommendations S 725 and 729). 3 Methods of measurement 3.1 General considerations The R
44、F pori of the ODU is often directly fitted with the antenna feed horn. In this case, it is necessary to separate the antenna and feed horn from the remaining part of the ODU by manufacturers instructions, to enable the measurement of the antenna parameters and the RF parameters at this interface poi
45、nt. Sometimes it may be necessary to use appropriate waveguide adapters and/or transducers to connect the measuring equipment with this interface point. In such a case, the performance of such adapters and/or transducers should be calibrated. When the antenna feed horn is connected to the ODU throug
46、h a feeder circuit, the feeder circuit may be included either in the antenna sub- system or in the ODU sub-system in the measurements, or its performance (ag. loss) may be measured separately, as appropriate. Where the loss of the feeder circuit is measured separately, that loss should be subtracted
47、 when calculating the equivalent isotropically radiated power (EIRP) of the VSAT (see 3.3.3, 3.3.8 and 3.3.9). Since the control function inside the VSAT usually inhibits emission of the output RF Sig- nal when the VSAT in the star type network does not receive the appropriate control signal from th
48、e hub station, it may be necessary to follow the manufacturers instructions to force the VSAT to emit the signal by disabling such control function or by using the hub simulator with network control and monitoring computer or its emulator which generates the control signal (see 3.5). Most of the mea
49、surements described in this standard are performed as type tests. , 3.2 Antenna See IEC 835-3-2. Ideally, the following items should be measured: a) on-axis gain; b) radiation pattern: c) cross-polarization discrimination. LbZLibb9 0587332 b93 = Page 6 EN 60836-3-13 : 1996 3.3 RF characteristics 3.3.1 3.3.1 -1 Method of measurement Transmit carrier frequency range, accuracy and stability See IEC 835-1-2. Enable transmission of a continuous wave carrier (preferably unmodulated) by appropriate local setting or remote control. Connect a frequency counter t
