1、BRITISH STANDARD BS EN 60835-3-9:1995 BS7573-3.9: 1995 IEC835-3-9: 1993 Methods of measurement for equipment used in digital microwave radio transmission systems Part3: Measurements on satellite earth stations Section3.9 Terminal equipment SCPC-PSK The European Standard EN60835-3-9:1995 has the stat
2、us of a BritishStandard ICS 33.060.30BSEN 60835-3-9:1995 This British Standard, having been prepared under the directionof the ElectrotechnicalSector Board, was published under the authorityof the Standards Boardand comes into effect on 15December1995 BSI 01-2000 The following BSI references relate
3、to the work on this standard: Committee reference EPL/12 Draft for comment 91/22367 DC ISBN 0 580 24962 X Committees responsible for this BritishStandard The preparation of this BritishStandard was entrusted to Technical Committee EPL/12, Radio communication, upon which the following bodies were rep
4、resented: British Broadcasting Corporation British Radio and Electronic Equipment Manufacturers Association British Telecommunications plc ERA Technology Ltd. Institution of Electrical Engineers Radio, Electrical and Television Retailers Association Radiocommunications Agency Amendments issued since
5、 publication Amd. No. Date CommentsBSEN 60835-3-9:1995 BSI 01-2000 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN 60835-3-9 3 List of references Inside back coverBSEN 60835-3-9:1995 ii BSI 01-2000 National foreword This BritishStandard has been p
6、repared by Technical Committee EPL/12 and is the English language version of EN60835-3-9:1995 Methods of measurement for equipment used in digital microwave radio transmission systems Part3:Measurements on satellite earth stations Section3.9 Terminal equipment SCPC-PSK, published by the European Com
7、mittee for Electrotechnical Standardization (CENELEC). It is identical with IEC835-3-9:1993, published by the International Electrotechnical Commission(IEC). BS EN60835 is published in three Parts. The other Parts are: Part1: Measurements common to terrestrial radio-relay systems and satellite earth
8、 stations; Part2: Measurements on terrestrial radio-relay systems. Some of the many Sections of the three Parts have appeared under the number BS7573, of the same generic title. When using this BritishStandard, reference is required to BS EN60835-1-1.2, BS EN60835-1-1.3 1)and BS EN60835-1-1.4 1) . T
9、his Section of BS EN 60835 covers methods of measurement on Single-Channel-Per-Carrier, Phase-Shift-Keying,(SCPC-PSK) terminal equipment using pulse code modulation(PCM) encoding. The terminal can be used in a pre-assigned mode or be integrated in a Demand Assignment Multiple Access(DAMA) network. T
10、he methods described are applicable to SCPC-PSK equipment used in international satellite systems and most of the methods are also applicable to systems used in domestic or regional satellite systems. A British Standard does not purport to include all the necessary provisions of a contract. Users of
11、 British Standards are responsible for their correct application. 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 title page, pages2 to18, an inside bac
12、k cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. 1) In preparation. Cross-references Publication referred to Corresponding BritishStandard BS EN60835 Method
13、s of measurement for equipment used in digital microwave radio transmission systems. Part1 Measurements common to terrestrial radio-relay systems and satellite earth stations EN60835-1-2:1993 (IEC835-1-2:1992) Section1.2:1995 Basic characteristics EN60835-1-3:1995 (IEC835-1-3:1992) Section1.3:1995 T
14、ransmission characteristics 1) EN60835-1-4:1992 (IEC835-1-4:1992) Section1.4:1995 Transmission performance 1)EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN60835-3-9 January1995 ICS 33.060.30 Descriptors: Telecommunications, radiocommunications, communication equipment, earth stations, microwav
15、e frequencies, digital technics, measurements, characteristics English version Methods of measurement for equipment used in digital microwave radio transmission systems Part3: Measurements on satellite earth stations Section9: Terminal equipment SCPC-PSK (IEC835-3-9:1993) Mthodes de mesure applicabl
16、es au matriel utilis pour les systmes de transmission numrique en hyperfrquence Partie3: Mesures applicables aux stations terriennes de tlcommunications par satellite Section9: Equipement terminal SCPC-MDP (CEI835-3-9:1993) Meverfahren fr Gerte in digitalen Mikrowellen-Funkbertragungssystemen Teil3:
17、 Messungen an Satelliten-Erdfunkstellen Hauptabschnitt9: SCPC-PSK-Endgerte (IEC835-3-9:1993) This European Standard was approved by CENELEC on1994-12-06. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the
18、 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 Secretariat or to any CENELEC member. This European Standard exists in three official versions(English, French, Germ
19、an). 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 official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark,
20、 Finland, 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 Elektrotechnisc
21、he Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1995 Copyright reserved to CENELEC members Ref. No. EN60835-3-9:1995 EEN 60835-3-9:1995 BSI 01-2000 2 Foreword The text of the International Standard IEC835-3-9:1993, prepared by SC12E, Radio-relay and fixed satellite communications
22、 systems, of IECTC12, Radiocommunications, was submitted to the formal vote and was approved by CENELEC as EN60835-3-9 on1994-12-06 without any modification. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. In this standard, Annex ZA is normative.
23、Annex ZA has been added by CENELEC. Contents Page Foreword 2 Introduction 3 1 Scope 3 2 Normative references 3 3 PCM channel codec 4 3.1 Idle channel noise level 4 3.2 Total distortion including quantizing distortion 4 3.3 Audio amplitude/frequency characteristics 5 3.4 PCM coder overload point 5 3.
24、5 Audio intermodulation products 5 3.6 Audio spurious output components 5 4 I.F. sub-system characteristics 5 4.1 Frequency accuracy and stability 5 4.2 Transmit i.f. spurious signals 5 4.3 I.F. intermodulation products 6 4.4 A.F.C. pull-in range and a.g.c. characteristics 6 4.5 I.F. amplitude/frequ
25、ency characteristics 8 4.6 I.F. return loss characteristics 8 5 Bit-error-ratio(BER) 8 Page 5.1 Continuous mode BER 8 5.2 Voice burst mode BER 8 5.3 Overall system performance with interference 8 6 Cycle-skipping performance 9 6.1 Definition and general considerations 9 6.2 Method of measurement 9 6
26、.3 Presentation of results 10 6.4 Details to be specified 10 Annex ZA (normative) Other international publications quoted in this standard with the references of the relevant European publications 18 Figure 1 Example of an SCPC-PSK terminal functional block diagram 11 Figure 2 Typical arrangement fo
27、r measuring PCM channel codec performance 12 Figure 3 Test arrangement for measuring the signal-to-total distortion ratio 12 Figure 4 Typical arrangement for measuring a.f.c. and a.g.c. functions 13 Figure 5 Typical arrangement for measuring BER performance (voice mode) 14 Figure 6 Typical arrangeme
28、nt for measuring BER performance (data mode) 15 Figure 7 Typical arrangement for measuring BER performance with interference(data mode) 16 Figure 8 Typical arrangement for measuring cycle-skipping performance (direct method) 17 latest date by which the EN has to be implemented at national level by p
29、ublication of an identical national standard or by endorsement (dop) 1995-12-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 1995-12-01EN 60835-3-9:1995 BSI 01-2000 3 Introduction A block diagram of a typical SCPC-PSK terminal is shown in Figure 1. T
30、he terminal may be divided into two portions; the channel units and the intermediate frequency(i.f.) sub-system. The channel units accept voice or data signals and modulate i.f. carriers, and vice versa. Only one voice or data channel is processed by a channel unit. Therefore, numbers of channel uni
31、ts, the number depending on the traffic requirements, are usually installed in an earth station. The channel units for voice and data are different. For example, on the transmit-side, a channel unit for voice accepts a voice signal and converts it to a PCM signal at56kbit/s. A voice detector is prov
32、ided to detect the existence of the voice signal and to radiate a carrier only while the voice signal is active. The output carrier therefore becomes a stream of short bursts. A channel synchronizer (transmit-side) attaches a preamble word at the beginning of each burst and inserts frame synchronizi
33、ng words at specified intervals. The output signal of the channel synchronizer, e.g.64kbit/s, is applied to a PSK modulator where biphase or quadriphase phase shift keying modulation is performed on the carrier. The output carrier frequency is controlled by a transmit frequency synthesizer. On the r
34、eceive-side, the received, PSK-modulated i.f. carrier is selected by a receive frequency synthesizer and demodulated by a PSK demodulator. The demodulated PCM signal, e.g.64kbit/s, is applied to a channel synchronizer(receive-side), and word synchronization is achieved. The voice signal is then reco
35、vered by a PCM decoder. In the case of a channel unit used for data signals, an incoming data signal, e.g.at a bit-rate of 48kbit/s or56kbit/s, is scrambled and combined with additional bits for error correction in a data encoder. The encoded signal, e.g.64kbit/s, is then applied to a PSK modulator
36、which is the same as that used for voice signals. On the receive-side, the recovered signal from the PSK demodulator is applied to a data decoder, where correct code synchronization is recovered and error correction is performed. The output signal of each PSK modulator is applied to an i.f. combiner
37、 in the i.f. sub-system and combined with each other. A reference pilot signal is also combined in the case of the reference earth station. The combined i.f. signal is amplified and sent to the up-converter in the earth station i.f./r.f. equipment. The received i.f. signal from the down-converter is
38、 first applied to automatic frequency control(a.f.c.) and automatic gain control(a.g.c.) circuits, where any frequency inaccuracy arising from the local oscillators of the satellite transponder and/or earth station i.f./r.f. equipment is corrected using the reference pilot signal. The a.g.c.function
39、 also uses the pilot signal. The output frequency of the a.f.c. and a.g.c. circuits may differ from the input frequency because of frequency conversion during the a.f.c. function. It may also differ between manufacturers equipment. The output signal is then divided by an i.f. divider and applied to
40、the PSK demodulator of the channel units. 1 Scope This section of IEC835-3 deals with methods of measurement on Single-Channel-Per-Carrier, Phase-Shift-Keying,(SCPC-PSK) terminal equipment utilizing PCM encoding. The SCPC-PSK terminal may be used in a pre-assigned mode or integrated in a Demand Assi
41、gnment Multiple Access(DAMA) network. The measurement methods described in this section are applicable to SCPC-PSK equipment used in international satellite systems. However, most of the methods of measurement will also be applicable to systems used in domestic or regional satellite systems. 2 Norma
42、tive references The following normative documents contain provisions which, through reference in this text, constitute provisions of this section of IEC835-3. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements bas
43、ed on this section of IEC835-3 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. IEC835-1-2:1992, Methods of measurement for equipment us
44、ed in digital microwave radio transmission systems Part1: Measurements common to terrestrial radio-relay systems and satellite earth stations Section2: Basic characteristics. EN 60835-3-9:1995 4 BSI 01-2000 IEC835-1-3:1992, Methods of measurement for equipment used in digital microwave radio transmi
45、ssion systems Part1: Measurements common to terrestrial radio-relay systems and satellite earth stations Section3: Transmission characteristics. IEC835-1-4:1992, Methods of measurement for equipment used in digital microwave radio transmission systems Part1: Measurements common to terrestrial radio-
46、relay and satellite earth stations Section4: Transmission performance. CCITT Recommendation G.712, Performance characteristics of PCM channels between4-wire interfaces at voice frequencies. CCITT RecommendationO.41, Specification for a psophometer for use on telephone type circuits. CCITT Recommenda
47、tionO.131, Specification for a quantizing distortion measuring apparatus using a pseudo-random noise stimulus. CCITT RecommendationO.132, Specification for a quantizing distortion measuring equipment using a sinusoidal test signal. 3 PCM channel codec The following methods of measurement are in acco
48、rdance with CCITT Recommendations (seeCCITT Recommendation G.712). The measurement can be performed by a loopback connection either at i.f., or at the digital side, of the PCM codec, whichever is the most convenient. A typical arrangement for measuring the performance of a PCM channel codec is shown
49、 in Figure 2. When the i.f. loopback connection method is used, the voice detector circuit shall be disabled so that the i.f. signal is transmitted regardless of the presence or absence of a voice input signal. 3.1 Idle channel noise level 3.1.1 Definition The idle channel noise level is the noise level at the output terminal of the PCM decoder in the absence of the input voice signal. 3.1.2 Method of measurement The idle channel noise level is measured by noise measuring equipment connected to the output terminal of the PCM deco