SIST EN 300 959 V8.1.2:2003

• Abstract:

  Release 99 CRs at SMG#30bis

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.070.50 - Global System for Mobile Communication (GSM)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI EN 300 959 V8.1.2 (2001-02) - Digital cellular telecommunications system (Phase 2+) (GSM); Modulation (GSM 05.04 version 8.1.2 Release 1999)

SIST EN 300 959 V8.1.2:2003 is the Slovenian adoption of ETSI EN 300 959 Version 8.1.2 for GSM modulation. It specifies how a GSM modulator turns bits from the encryption unit into an RF signal, so it is for people designing, verifying, or testing GSM radio equipment.

What does SIST EN 300 959 V8.1.2:2003 specify?

SIST EN 300 959 V8.1.2:2003 specifies the modulation format used in the digital cellular telecommunications system (Phase 2+) (GSM). It covers the signal processing needed to generate the transmit RF signal from the incoming bit stream, and it includes both GMSK and 8PSK.

The document also states what is outside its scope. RF filtering needed for spectral purity, and the tolerances linked to the theoretical filter requirements, are handled in GSM05.05 instead.

The structure is straightforward:

• Scope
• References
• Abbreviations
• Clause 2 - Modulation format for GMSK
• Clause 3 - Modulation format for 8PSK
• Annex A - informative change control history

This version reflects Release 99 change requests at SMG#30bis, so readers can treat it as a Release 1999 GSM modulation reference.

What are the key requirements of SIST EN 300 959 V8.1.2:2003?

SIST EN 300 959 V8.1.2:2003 gives the modulation rules that define how GSM transmit bursts are formed and driven. In practice, these rules matter because they determine the symbol rate, burst boundaries, symbol mapping, and phase behaviour that a transmitter must implement.

GMSK modulation in Clause 2

Clause 2 sets the GMSK modulating symbol rate at 1625/6 ksymb/s, which is the same numerical rate used for the bit stream. For a transmitter, that means the baseband timing must match the GSM burst structure exactly.

Clause 2 explains how the start and stop of the burst are handled with dummy bits. For normal bursts, the useful part lasts for 147 modulating bits, and the modulator state outside that useful part is not specified.

Clause 2 also defines differential encoding and the linear filter used to shape the modulating values. The practical point is that the transmitted phase is not a raw bit-by-bit switch - it is the result of differential coding and controlled pulse shaping.

The output phase is defined relative to the start of the active part of the burst, with a modulation index of 1/2. For implementers, that means the phase trajectory has to follow the GSM timing reference used in GSM05.02.

8PSK modulation in Clause 3

Clause 3 sets the 8PSK modulating symbol rate at 1625/6 ksymb/s, corresponding to 3 times the bit rate used for the symbol grouping. This tells designers how to align the serial bit stream with symbol processing.

Clause 3 maps the modulating bits in groups of three using Gray mapping. In practice, that reduces the chance of large symbol errors when only one bit changes.

The clause also defines symbol rotation by 3π/8 radians per symbol before pulse shaping. This is important because the transmitter must apply the rotation before the signal is shaped and sent to RF.

Clause 3 uses a linearised GMSK pulse for pulse shaping and then defines the modulated RF carrier during the useful part of the burst. That means 8PSK is not just a phase map - it is a complete transmit signal description, including shaping and carrier generation.

What terms does SIST EN 300 959 V8.1.2:2003 define?

• GMSK - the modulation format covered in Clause 2 for GSM burst transmission.
• 8PSK - the modulation format covered in Clause 3, using groups of three bits per symbol.
• dummy bits - bits assumed before and after the burst so the GMSK modulator has a defined internal state.
• tail bits - the bits that mark the start and stop of the active and useful part of a burst.
• active part of the burst - the part of the burst where the modulator is driven by the burst bit stream.
• useful part of the burst - the portion of the burst for which the modulation behaviour is specified.
• RF - Radio Frequency, the carrier signal produced by the modulator.
• symbol rotation - the fixed per-symbol phase rotation applied to 8PSK symbols before pulse shaping.

Who uses SIST EN 300 959 V8.1.2:2003?

SIST EN 300 959 V8.1.2:2003 is used by engineers and test teams working on GSM Phase 2+ radio transmitters. It is relevant to modem, baseband, and RF designers because it specifies how bits become a modulated RF burst.

It is also used by verification and conformance laboratories checking burst timing, symbol mapping, and modulation behaviour. Quality managers and buyers can use it to confirm that a GSM radio product is being designed or tested against the correct modulation reference.

What changed in SIST EN 300 959 V8.1.2:2003 from the previous edition?

Version 8.1.2 is published as an update to the earlier 8.1.1 text. The change control history also records:

• conversion to Release 97
• introduction of 8PSK for EDGE
• correction of a mistake in the range of alpha-sub-i in Clause 2.3
• replacement of Figure 3 after corruption
• publication update to Version 8.1.2

Which standards are used with SIST EN 300 959 V8.1.2:2003?

SIST EN 300 959 V8.1.2:2003 relies on these GSM documents:

• GSM01.04 - supplies abbreviations and acronyms used in the document.
• GSM05.01 - gives the general description of the physical layer on the radio path.
• GSM05.02 - defines multiplexing and multiple access on the radio path, including burst structure.
• GSM05.05 - covers radio transmission and reception, including the RF filtering and tolerance topics that are outside this document's scope.

What does the SIST EN 300 959 V8.1.2:2003 document contain?

The document contains the modulation rules for two GSM transmit formats, with equations for differential encoding, filtering, symbol rotation, and RF carrier generation. Clause 2 and Clause 3 each set out the timing and signal-processing steps needed to build the burst waveform.

It also includes a bit-to-symbol mapping table for 8PSK and figures showing how the active part, useful part, and tail bits relate in a burst. Those visuals are mainly for implementers checking burst timing and signal state.

Annex A is informative and gives the change control history, which is useful when tracking how the specification reached Version 8.1.2.

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digital cellular telecommunications system (Phase 2+) (GSM); Modulation (GSM 05.04 version 8.1.2 Release 1999)33.070.50Globalni sistem za mobilno telekomunikacijo (GSM)Global System for Mobile Communication (GSM)ICS:Ta slovenski standard je istoveten z:EN 300 959 Version 8.1.2SIST EN 300 959 V8.1.2:2003en01-december-2003SIST EN 300 959 V8.1.2:2003SLOVENSKI
STANDARD
ETSIEN300959V8.1.2(2001-02)EuropeanStandard(Telecommunicationsseries)Digitalcellulartelecommunicationssystem(Phase2+);Modulation(GSM05.04version8.1.2Release1999)GLOBALSYSTEMFORMOBILECOMMUNICATIONSRSIST EN 300 959 V8.1.2:2003

ETSIETSIEN300959V8.1.2(2001-02)2(GSM05.04version8.1.2Release1999)ReferenceREN/SMG-020504Q8KeywordsDigitalcellulartelecommunicationssystem,GlobalSystemforMobilecommunications(GSM)ETSI650RoutedesLuciolesF-06921SophiaAntipolisCedex-FRANCETel.:[phone]Fax:[phone]SiretN°34862356200017-NAF742CAssociationàbutnonlucratifenregistréeàlaSous-PréfecturedeGrasse(06)N°7803/88ImportantnoticeIndividualcopiesofthepresentdocumentcanbedownloadedfrom:http://www.etsi.orgThepresentdocumentmaybemadeavailableinmorethanoneelectronicversionorinprint.Inanycaseofexistingorperceiveddifferenceincontentsbetweensuchversions,thereferenceversionisthePortableDocumentFormat(PDF).Incaseofdispute,thereferenceshallbetheprintingonETSIprintersofthePDFversionkeptonaspecificnetworkdrivewithinETSISecretariat.Usersofthepresentdocumentshouldbeawarethatthedocumentmaybesubjecttorevisionorchangeofstatus.InformationonthecurrentstatusofthisandotherETSIdocumentsisavailableathttp://www.etsi.org/tb/status/Ifyoufinderrorsinthepresentdocument,sendyourcommentto:[e-mail]opartmaybereproducedexceptasauthorizedbywrittenpermission.Thecopyrightandtheforegoingrestrictionextendtoreproductioninallmedia.©EuropeanTelecommunicationsStandardsInstitute2001.Allrightsreserved.SIST EN 300 959 V8.1.2:2003

ETSIETSIEN300959V8.1.2(2001-02)3(GSM05.04version8.1.2Release1999)ContentsIntellectualPropertyRights.4Foreword.41Scope.51.1References.51.2Abbreviations.52ModulationformatforGMSK.52.1Modulatingsymbolrate.52.2Startandstopoftheburst.52.3Differentialencoding.62.4Filtering.62.5Outputphase.72.6Modulation.73Modulationformatfor8PSK.73.1Modulatingsymbolrate.73.2Symbolmapping.73.3Startandstopoftheburst.83.4Symbolrotation.93.5Pulseshaping.93.6Modulation.9AnnexA(informative):Changecontrolhistory.10History.11SIST EN 300 959 V8.1.2:2003

ETSIETSIEN300959V8.1.2(2001-02)4(GSM05.04version8.1.2Release1999)IntellectualPropertyRightsIPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.TheinformationpertainingtotheseessentialIPRs,ifany,ispubliclyavailableforETSImembersandnon-members,andcanbefoundinETSISR000314:"IntellectualPropertyRights(IPRs);Essential,orpotentiallyEssential,IPRsnotifiedtoETSIinrespectofETSIstandards",whichisavailablefromtheETSISecretariat.LatestupdatesareavailableontheETSIWebserver(http://www.etsi.org/ipr).PursuanttotheETSIIPRPolicy,noinvestigation,includingIPRsearches,hasbeencarriedoutbyETSI.NoguaranteecanbegivenastotheexistenceofotherIPRsnotreferencedinETSISR000314(ortheupdatesontheETSIWebserver)whichare,ormaybe,ormaybecome,essentialtothepresentdocument.ForewordThisEuropeanStandard(Telecommunicationsseries)hasbeenproducedbyETSITechnicalCommitteeSpecialMobileGroup(SMG).Thepresentdocumentspecifiesthemodulationformatusedwithinthedigitalcellulartelecommunicationssystem.ThecontentsofthepresentdocumentmaybesubjecttocontinuingworkwithinSMGandmaychangefollowingformalSMGapproval.ShouldSMGmodifythecontentsofthepresentdocumentitwillthenbere-submittedforformalapprovalproceduresbyETSIwithanidentifyingchangeofreleasedateandanincreaseinversionnumberasfollows:Version8.x.ywhere:8GSMPhase2+Release1999.xtheseconddigitisincrementedforchangesofsubstance,i.e.technicalenhancements,corrections,updates,etc.;ythethirddigitisincrementedwheneditorialonlychangeshavebeenincorporatedinthespecification.NationaltranspositiondatesDateofadoptionofthisEN:2February2001DateoflatestannouncementofthisEN(doa):31May2001DateoflatestpublicationofnewNation
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