SIST EN 60835-3-9:2002

Methods of measurement for equipment used in digital microwave radio transmission systems -- Part 3: Measurement on satellite earth stations -- Section 9: Terminal equipment SCPC-PSK

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 assignment multiple access (DAMA) network.

Meßverfahren für Geräte in digitalen Mikrowellen-Funkübertragungssystemen -- Teil 3: Messungen an Satelliten-Erdfunkstellen -- Hauptabschnitt 9: SCPC-PSK-Endgeräte

Méthodes de mesure applicables au matériel utilisé pour les systèmes de transmission numérique en hyperfréquence -- Partie 3: Mesures applicables aux stations terriennes de télécommunications par satellite -- Section 9: Equipement terminal SCPC-MDP

Traite des méthodes de mesure du système à porteuse monovoie, modulé par déplacement de phase (SCPC-MDP), de l'équipement terminal utilisant le codage MIC. L'équipement terminal SCPC-MDP peut être utilisé en mode pré-assigné ou intégré à un réseau à accès multiple avec assignation en fonction de la demande, (DAMA).

Methods of measurement for equipment used in digital microwave radio transmission systems - Part 3: Measurement on satellite earth stations - Section 9: Terminal equipment SCPC-PSK (IEC 60835-3-9:1993)

General Information

• Status: Published
• Publication Date: 30-Sep-2002
• ICS: 33.060.30 - Radio relay and fixed satellite communications systems
• Technical Committee: OMS - Equipment used in mobile services and satelite comunication systems
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Oct-2002
• Due Date: 01-Oct-2002
• Completion Date: 01-Oct-2002
• Ref Project: EN 60835-3-9:1995 - Methods of measurement for equipment used in digital microwave radio transmission systems - Part 3: Measurement on satellite earth stations - Section 9: Terminal equipment SCPC-PSK

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Methods of measurement for equipment used in digital microwave radio transmission systems - Part 3: Measurement on satellite earth stations - Section 9: Terminal equipment SCPC-PSK (IEC 60835-3-9:1993)Meßverfahren für Geräte in digitalen Mikrowellen-Funkübertragungssystemen -- Teil 3: Messungen an Satelliten-Erdfunkstellen -- Hauptabschnitt 9: SCPC-PSK-EndgeräteMéthodes de mesure applicables au matériel utilisé pour les systèmes de transmission numérique en hyperfréquence -- Partie 3: Mesures applicables aux stations terriennes de télécommunications par satellite -- Section 9: Equipement terminal SCPC-MDPMethods of measurement for equipment used in digital microwave radio transmission systems -- Part 3: Measurement on satellite earth stations -- Section 9: Terminal equipment SCPC-PSK33.060.30Radiorelejni in fiksni satelitski komunikacijski sistemiRadio relay and fixed satellite communications systemsICS:Ta slovenski standard je istoveten z:EN 60835-3-9:1995SIST EN 60835-3-9:2002en01-oktober-2002SIST EN 60835-3-9:2002SLOVENSKI
STANDARD



SIST EN 60835-3-9:2002



SIST EN 60835-3-9:2002



SIST EN 60835-3-9:2002



SIST EN 60835-3-9:2002



SIST EN 60835-3-9:2002



NORMECEIINTERNATIONALEIECINTERNATIONAL60835-3-9STAN DARDPremière éditionFirst edition1993-05Méthodes de mesure applicables au matérielutilisé pour les systèmes de transmissionnumérique en hyperfréquencePartie 3:Mesures applicables aux stations terriennesde télécommunications par satelliteSection 9: Equipement terminal SCPC-MDPMethods of measurement for equipment used indigital microwave radio transmission systemsPart 3:Measurements on satellite earth stationsSection 9: Terminal equipment SCP-PSK© IEC 1993 Droits de reproduction réservés — Copyright - all rights reservedAucune partie de cette publication ne peut être reproduite niNo part of this publication may be reproduced or utilized inutilisée sous quelque forme que ce soit et par aucunany form or by any means, electronic or mechanical,procédé, électronique ou mécanique, y compris la photo-including photocopying and microfilm, without permission incopie et les microfilms, sans l'accord écrit de l'éditeur.writing from the publisher.International Electrotechnical Commission3, rue de Varembé Geneva, SwitzerlandTelefax: [phone]e-mail: [e-mail] web site http: //www.iec.chIEC•Commission Electrotechnique InternationaleInternational Electrotechnical CommissionMcHtayHapouuaR 311e11TpoTeXHN4eCHaA Î{OMHCCNA•CODE PRIXPRICE CODEPour prix, voir catalogue en vigueurFor price, see current catalogueSIST EN 60835-3-9:2002



835-3-9 © IEC: 1993- 3 -CONTENTSPageFOREWORD 7INTRODUCTION 9Clause1Scope 112Normative references 113 PCM channel codec 133.1Idle channel noise level 133.2Total distortion including quantizing distortion 133.3Audio amplitude/frequency characteristics
153.4 PCM coder overload point
153.5Audio intermodulation products
173.6 Audio spurious output components
174I.F. sub-system characteristics
194.1Frequency accuracy and stability
194.2Transmit i.f. spurious signals
194.3I.F. intermodulation products 194.4A.F.C. pull-in range and a.g.c. characteristics 214.5I.F. amplitude/frequency characteristics
274.6I.F. return loss characteristics 275Bit-error-ratio (BER) 295.1 Continuous mode BER 295.2 Voice burst mode BER 295.3 Overall system performance with interference 316 Cycle-skipping performance 336.1Definition and general considerations 336.2 Method of measurement
356.3Presentation of results
356.4Details to be specified
35SIST EN 60835-3-9:2002



835-3-9 © I EC: 1993– 5 –Figures1 – Example of an SCPC-PSK terminal functional block diagram 372 – Typical arrangement for measuring PCM channel codec performance 393 – Test arrangement for measuring the signal-to-total distortion ratio 414 – Typical arrangement for measuring a.f.c. and a.g.c. functions 435 – Typical arrangement for measuring BER performance (voice mode)
456 – Typical arrangement for measuring BER performance (data mode) 477 – Typical arrangement for measuring BER performance with interference(data mode) 498 – Typical arrangement for measuring cycle-skipping performance(direct method)
51SIST EN 60835-3-9:2002



835-3-9 © IEC: 1993– 7 –INTERNATIONAL ELECTROTECHNICAL COMMISSIONMETHODS OF MEASUREMENT FOR EQUIPMENTUSED IN DIGITAL MICROWAVERADIO TRANSMISSION SYSTEMSPart 3: Measurements on satelliteearth stationsSection 9 - Terminal equipment SCPC-PSKFOREWORD1)The IEC (International Electrotechnical Commission) is a worldwide organization for standardizationcomprising all national electrotechnical committees (IEC National Committees). The object of the IEC is topromote international cooperation on all questions concerning standardization in the electrical andelectronic fields. To this end and in addition to other activities, the IEC publishes International Standards.Their preparation is entrusted to technical committees; any IEC National Committee interested inthe subject dealt with may participate in this preparatory work. International, governmental andnon-governmental organizations liaising with the IEC also participate in this preparation. The IECcollaborates closely with the International Organization for Standardization (ISO) in accordance withconditions determined by agreement between the two organizations.2)The formal decisions or agreements of the IEC on technical matters, prepared by technical committees onwhich all the National Committees having a special interest therein are represented, express, as nearly aspossible, an international consensus of opinion on the subjects dealt with.3)They have the form of recommendations for international use published in the form of standards, technicalreports or guides and they are accepted by the National Committees in that sense.4)In order to promote international unification, IEC National Committees undertake to apply IEC InternationalStandards transparently to the maximum extent possible in their national and regional standards. Anydivergence between the IEC Standard and the corresponding national or regional standard shall be clearlyindicated in the latter.International Standard IEC 835-3-9 has been prepared by sub-committee 12E: Radio-relayand fixed satellite communications systems, of IEC technical committee 12: Radio-communications.The text of this standard is based on the following documents:DISReport on Voting
12E(CO)14212E(CO)152Full information on the voting for the approval of this standard can be found in the reporton voting indicated in the above table.SIST EN 60835-3-9:2002



835-3-9 © IEC: 1993- 9 -INTRODUCTIONA block diagram of a typical SCPC-PSK terminal is shown in figure 1. The terminal may bedivided 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, andvice versa. Only one voice or data channel is processed by a channel unit. Therefore,numbers of channel units, the number depending on the traffic requirements, are usuallyinstalled 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 andconverts it to a PCM signal at 56 kbit/s. A voice detector is provided to detect theexistence 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 framesynchronizing words at specified intervals. The output signal of the channel synchronizer,e.g. 64 kbit/s, is applied to a PSK modulator where biphase or quadriphase phase shiftkeying modulation is performed on the carrier. The output carrier frequency is controlledby a transmit frequency synthesizer.On the receive-side, the received, PSK-modulated i.f. carrier is selected by a receivefrequency synthesizer and demodulated by a PSK demodulator. The demodulated PCMsignal, e.g. 64 kbit/s, is applied to a channel synchronizer (receive-side), and wordsynchronization is achieved. The voice signal is then recovered by a PCM decoder.In the case of a channel unit used for data signals, an incoming data signal, e.g. at abit-rate of 48 kbit/s or 56 kbit/s, is scrambled and combined with additional bits for errorcorrection in a data encoder. The encoded signal, e.g. 64 kbit/s, is then applied to a PSKmodulator which is the same as that used for voice signals. On the receive-side, therecovered signal from the PSK demodulator is applied to a data decoder, where correctcode synchronization is recovered and error correction is performed.The output signal of each PSK modulator is applied to an i.f. combiner in the i.f.sub-system and combined with each other. A reference pilot signal is also combined in thecase of the reference earth station. The combined i.f. signal is amplified and sent to theup-converter in the earth station i.f./r.f. equipment. The received i.f. signal from thedown-converter is first applied to automatic frequency control (a.f.c.) and automatic gaincontrol (a.g.c.) circuits, where any frequency inaccuracy arising from the local oscillatorsof the satellite transponder and/or earth station i.f./r.f. equipment is corrected using thereference pilot signal. The a.g.c. function also uses the pilot signal. The output frequencyof the a.f.c. and a.g.c. circuits may differ from the input frequency because of frequencyconversion 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 the PSK demodulator ofthe channel units.SIST EN 60835-3-9:2002



835-3-9 © IEC: 1993- 11 -METHODS OF MEASUREMENT FOR EQUIPMENTUSED IN DIGITAL MICROWAVERADIO TRANSMISSION SYSTEMSPart 3: Measurements on satelliteearth stationsSection 9 - Terminal equipment SCPC-PSK1 ScopeThis section of IEC 835-3 deals with methods of measurement on Single-Channel-Per-Carrier, Phase-Shift-Keying, (SCPC-PSK) terminal equipment utilizing PCM encoding. TheSCPC-PSK terminal may be used in a pre-assigned mode or integrated in a DemandAssignment Multiple Access (DAMA) network.The measurement methods described in this section are applicable to SCPC-PSKequipment used in international satellite systems. However, most of the methods ofmeasurement will also be applicable to systems used in domestic or regional satellitesystems.2 Normative referencesThe following normative documents contain provisions which, through reference in thistext, constitute provisions of this section of IEC 835-3. At the time of publication, theeditions indicated were valid. All normative documents are subject to revision, and partiesto agreements based on this section of IEC 835-3 are encouraged to investigate thepossibility of applying the most recent editions of the normative documents indicatedbelow. Members of IEC and ISO maintain registers of currently valid InternationalStandards.IEC 835-1-2: 1992, Methods of measurement for equipment used in digital microwaveradio transmission systems - Part 1: Measurements common to terrestrial radio-relaysystems and satellite earth stations - Section 2: Basic characteristicsIEC 835-1-3: 1992, Methods of measurement for equipment used in digital microwaveradio transmission systems - Part 1: Measurements common to terrestrial radio-relaysystems and satellite earth stations - Section 3: Transmission characteristicsIEC 835-1-4: 1992, Methods of measurement for equipment used in digital microwaveradio transmission systems - Part 1: Measurements common to terrestrial radio-relay andsatellite earth stations - Section 4: Transmission performanceCCITT Recommendation G.712: Performance characteristics of PCM channels between4-wire interfaces at voice frequenciesSIST EN 60835-3-9:2002



835-3-9 ©IEC: 1993–13 –CCITT Recommendation 0.41: Specification for a psophometer for use on telephone –type circuitsCCITT Recommendation 0.131: Specification for a quantizing distortion measuringapparatus using a pseudo-random noise stimulusCCITT Recommendation 0.132: Specification for a quantizing distortion measuringequipment using a sinusoidal test signal3 PCM channel codecThe following methods of measurement are in accordance with CCITT Recommendations(see CCITT Recommendation G.712). The measurement can be performed by a loopbackconnection either at i.f., or at the digital side, of the PCM codec, whichever is the mostconvenient. A typical arrangement for measuring the performance of a PCM channelcodec is shown in figure 2. When the i.f. loopback connection method is used, the voicedetector circuit shall be disabled so that the i.f. signal is transmitted regardless of thepresence or absence of a voice input signal.3.1 Idle channel noise level3.1.1DefinitionThe idle channel noise level is the noise level at the output terminal of the PCM decoder inthe absence of the input voice signal.3.1.2 Method of measurementThe idle channel noise level is measured by noise measuring equipment connected to theoutput terminal of the PCM decoder with the input port of the PCM coder terminated by amatched load (see figure 2). A noise weighting network as specified in CCITTRecommendation 0.41 should be used.3.1.3 Presentation of resultsThe results should be expressed in dBmOp, that is, psophometrically weighted noise levelwith reference to the test tone level.3.1.4 Details to be specifiedThe following items should be included, as required, in the detailed equipmentspecification:a)the maximum permitted idle channel noise level;b)loopback connection method applied.3.2 Total distortion including quantizing distortion3.2.1DefinitionThe signal-to-total distortion (including quantizing distortion) ratio is the ratio of the voicesignal level to the total distortion level at the output terminal of the PCM decoder.SIST EN 60835-3-9:2002



835-3-9 © IEC: 1993- 15 -3.2.2 Method of measurementThe measurement can be performed by either of two methods. According to the firstmethod given in CCITT Recommendation 0.131, and shown in figure 3, a band-limitedpseudo-random noise signal (via filter F1, 350 Hz to 550 Hz), is applied to the inputterminal of the PCM coder at specified levels (e.g. in the range of -60 to 0 dBmO). At eachlevel, the noise at the PCM decoder output terminal is measured by a noise receiver in twobands; first in the band 350 Hz to 550 Hz via filter F1, then in the band 800 Hz to 3 400 Hzvia filter F2. The signal-to-total distortion ratio, given by the difference in decibelsbetween the levels thus measured, has to be scaled from the measuring band of filter F2(800 Hz to 3 400 Hz), to the total voice channel band (300 Hz to 3 400 Hz) by a factorequal to the ratio of these bands, that is by adding 0,76 dB to the result of themeasurement.According to the second method given in CCITT Recommendation 0.132, a sinusoidal testsignal is applied to the input terminal of the PCM coder at specified levels (e.g. in the levelrange given above). At each input level, the signal level at the PCM decoder output ismeasured. The test signal is then blocked by a narrow band rejection filter, and the totaldistortion product is measured by an r.m.s., or quasi-r.m.s., detector via a standardtelephony noise weighting filter (see CCITT Recommendation 0.41). The signal-to-totaldistortion ratio is given by the difference in decibels between the two measured levels.This has to be scaled by a correction factor which is the difference in decibels between themeasuring bandwidth, excluding the stop-band at the rejection frequency, and the totalmeasuring bandwidth including the stop-band.3.2.3 Presentation of resultsThe results should be expressed in decibels and, for preference, should be presented inthe form of a graph with the input signal level as the abscissa.3.2.4 Details to be specifiedThe following items should be included, as required, in the detailed equipmentspecification:a)measurement method used (noise or sinusoidal test signals);b)the minimum required signal-to-total distortion ratio mask (in decibels);c)input signal level range;d)loopback connection method applied.3.3 Audio amplitude/frequency characteristicsSee IEC 835-1-3.3.4 PCM coder overload point3.4.1DefinitionThe overload point of the PCM coder is the level of the input signal which results in thefirst appearance of the highest positive or negative PCM output code, e.g. +111111or -111111.SIST EN 60835-3-9:2002



835-3-9 © I EC: 1993- 17 -3.4.2 Method of measurementA test signal is applied from a low-frequency generator to the PCM coder input terminal atthe reference frequency, and its level is increased until the highest PCM output code firstappears. This can be observed by displaying the PCM coder output pulses on anoscilloscope synchronized by the PCM clock signal and the start of limiting can be notedor, alternatively and if available, by observing the overload indicator lamp of the coder.3.4.3 Presentation of resultsThe results should be expressed in dBmO, together with the measuring frequency.3.4.4 Details to be specifiedThe following items should be included, as required, in the detailed equipmentspecification:a)measuring frequency;b)permitted range of input levels resulting in overload.3.5 Audio intermodulation productsSee IEC 835-1-2.The two audio frequency signals are added by a hybrid or a resistive adder, and thenapplied to the PCM coder.3.6 Audio spurious output componentsSee IEC 835-1-2.The out-of-band components with in-band signals, and the in-band components with out-of-band signals, should be measured.The following additional items should be included, as required, in the detailedspecification:a)frequency range and level range of the in-band signals;b)frequency range and level range of the out-of-band signals.SIST EN 60835-3-9:2002



835-3-9 © IEC: 1993- 19 -4 I.F. sub-system characteristics4.1 Frequency accuracy and stabilitySee IEC 835-1-2.The frequency accuracy and stability of various oscillators, such as the synthesizerreference oscillator, the digital clock source, the reference pilot oscillator, the PSKmodulator carrier oscillator, PSK demodulator local oscillator, etc., shall be measured.Direct measurement of the i.f. output frequency of the PSK modulators usually is notnecessary because it is synthesized from, and determined by, the frequencies of thereference oscillators. The stability measurement takes a long time, e.g. 1 month.Therefore, submission of the factory data may be permitted in lieu of witnessed tests.4.2 Transmit i.f. spurious signalsSee IEC 835-1-2.In SCPC-PSK terminal equipment, many kinds of frequency sources are utilized, e.g.modulator reference oscillators, frequency synthesizer reference oscillators, digital clocksources, etc., and they may be potential causes of spurious signals in the transmit i.f.signal either by themselves or in combination. Therefore, during this measurement, all thefrequency sources and the relevant circuits shall be in the "ON" condition wheneverpracticable.The modulator and demodulator section, including the PCM codec or any digitalprocessing sub-system, should be connected to the i.f. sub-system. One carrier at a time,with no modulation, shall be activated. The level of spurious signals within the specifiedfrequency range shall be measured. The measurement shall be made by varying thecarrier frequency across the specified bandwidth range whenever practicable.4.3 /.F. intermodulation productsSee IEC 835-1-2.A number of SCPC carriers are amplified and/or frequency converted together in the i.f.sub-system. The intermodulation products generated should be less than a specified level.Because the level of the intermodulation products caused by the multicarrier signal isrelated to that of two tones with the same total power, the two-tone measurement methodis usually employed. The third order intermodulation products, i.e. at frequencies of2 fi - f2 and 2 f2 - f, shall be measured. The measurement shall be performed for boththe transmit-side and the receive-side of the i.f. sub-system.The total power of the two test signals should be equal to or related to the nominal totalpower of the multicarrier signal applied to the syst
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