SIST EN 300 723 V7.0.2:2003

• Abstract:

  SUBJECT Addition of mu-law (PCS 1900).

• 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
• Mandate: T-172
• Ref Project: ETSI EN 300 723 V7.0.2 (1999-12) - Digital cellular telecommunications system (Phase 2+) (GSM); Enhanced Full Rate (EFR) speech processing functions; General description (GSM 06.51 version 7.0.2 Release 1998)

SIST EN 300 723 V7.0.2:2003 is the Slovenian adoption of ETSI EN 300 723, a European Telecommunications series standard for GSM Phase 2+ Enhanced Full Rate (EFR) speech processing functions. It gives the general description of the EFR speech path, including transcoding, discontinuous transmission, voice activity detection, comfort noise, lost-frame handling, and code homing, and points to the companion ENs that specify each function in detail.

What does SIST EN 300 723 V7.0.2:2003 specify?

SIST EN 300 723 V7.0.2:2003 introduces the GSM 06.60, 06.61, 06.62, 06.81 and 06.82 ENs that define the speech processing functions for the Enhanced Full Rate channel of the GSM system. In practice, it is a roadmap to the detailed codec and channel-processing standards rather than the full detailed specification itself.

The document is organized into a short scope, references, definitions and abbreviations, a general overview, and separate clauses for:

• Enhanced Full Rate speech channel transcoding
• Enhanced Full Rate speech channel discontinuous transmission (DTX)
• Enhanced Full Rate speech channel Voice Activity Detection (VAD)
• Enhanced Full Rate speech channel comfort noise insertion
• Enhanced Full Rate speech channel lost speech frame substitution and muting
• Enhanced Full Rate code homing

Annex A is informative and gives the change request history.

What are the key requirements of SIST EN 300 723 V7.0.2:2003?

SIST EN 300 723 V7.0.2:2003 describes how the EFR speech chain is structured and how its major functions behave. The practical value is that implementers can see which companion standard governs each function and what interfaces and test expectations apply.

Transcoding and speech coding

Clause 5 states that the speech encoder takes 13-bit uniform PCM input, either directly from the Mobile Station (MS) or from the PSTN after 8-bit A-law or mu-law (PCS 1900) conversion. The encoded speech is then passed to GSM 05.03 channel coding. In practice, this tells designers where conversion happens and how the speech codec connects to radio channel coding.

Clause 5 also identifies the coding scheme as Algebraic Code Excited Linear Prediction (ACELP) and links compliance checking to GSM 06.53 C code and GSM 06.54 digital test sequences. That matters for interoperability and conformance testing.

DTX, VAD and comfort noise

Clause 6 explains Discontinuous Transmission (DTX): the transmitter is active only when frames contain useful information. The document connects DTX to battery saving in the MS and reduced Radio Frequency (RF) interference on the air interface. It also identifies the supporting functions: VAD, background noise evaluation, and comfort noise generation.

Clause 7 states that the VAD decides whether each 20 ms speech frame contains speech or not. The VAD flag feeds the TX DTX handler, but it does not key the transmitter directly. This is important because implementation must preserve the defined control flow.

Clause 8 describes comfort noise insertion to avoid an abrupt drop in background noise when transmission stops. The process uses noise evaluation, SID frames, SID decoding, and comfort noise generation at the receiver.

Lost-frame handling

Clause 9 states that lost speech frames are replaced by predicted frames based on previous frames, and that silence frames are not allowed. For multiple consecutive losses, muting is used. In practice, this defines the receiver behavior when radio errors or frame stealing disrupt the stream.

Bit exact behavior and homing

Clause 10 says the transcoder, VAD, DTX system and comfort noise parts are defined in bit-exact arithmetic. The modules must produce the same output for a given input sequence when they start from the same state. It also defines homing behavior using special inband signalling frames so that modules can be reset for type approval, infrastructure approval, and remote testing.

What terms does SIST EN 300 723 V7.0.2:2003 define?

SIST EN 300 723 V7.0.2:2003 uses a focused set of GSM speech-processing terms and abbreviations.

• ACELP - Algebraic Code Excited Linear Prediction, the speech coding scheme used for EFR transcoding.
• DTX - Discontinuous Transmission, a mode that sends only frames with useful information.
• VAD - Voice Activity Detector, the function that decides whether a frame contains speech.
• SID - SIlence Descriptor, the frame used to carry comfort-noise information.
• SP - SPeech flag, which marks speech information versus SID information.
• BFI - Bad Frame Indication, used when received information is corrupted or missing.
• TAF - Time Alignment Flag, which marks the position of the SID frame within the SACCH multiframe.

Who uses SIST EN 300 723 V7.0.2:2003?

SIST EN 300 723 V7.0.2:2003 is used by engineers and test teams working on GSM Enhanced Full Rate speech processing in mobile stations, radio subsystems, and network equipment. It is also relevant to people preparing type approval and to those doing remote control and maintenance testing, because the document explicitly links homing behavior to those tasks.

Quality and compliance teams use it to check that implementations follow the defined codec behavior and the companion test materials. Equipment buyers can use it to confirm that a product supports the EFR speech-processing functions expected in GSM Phase 2+ systems.

What changed in SIST EN 300 723 V7.0.2:2003 from the previous edition?

Annex A records the change request history. The listed substantive change is the addition of mu-law (PCS 1900), and the history also notes the update to Version 7.0.2 for publication.

Which standards are used with SIST EN 300 723 V7.0.2:2003?

Clause 2 names the standards that support this document:

• GSM 01.04 - abbreviations and acronyms used in GSM documents
• GSM 03.50 - transmission planning aspects of the speech service in the GSM PLMN system
• GSM 05.03 - channel coding
• GSM 06.53 - ANSI-C code for the GSM EFR speech codec
• GSM 06.54 - test vectors for the GSM EFR speech codec
• GSM 06.60 - Enhanced Full Rate speech transcoding
• GSM 06.61 - substitution and muting of lost frames for EFR speech traffic channels
• GSM 06.62 - comfort noise aspects for EFR speech traffic channels
• GSM 06.81 - DTX for EFR speech traffic channels
• GSM 06.82 - VAD for EFR speech traffic channels

These references supply the detailed algorithms, code, and test vectors that this overview points to.

What does the SIST EN 300 723 V7.0.2:2003 document contain?

SIST EN 300 723 V7.0.2:2003 contains a system-level overview of the EFR speech path and a reference configuration figure that shows where each speech-processing function sits between the MS audio path, the radio interface, and the PSTN. It also explains how A-law or mu-law conversion, PCM speech samples, SID frames, SP and TAF flags, and radio subsystem interaction fit together.

The document does not reproduce the detailed codec algorithms, VAD logic, comfort-noise procedure, or lost-frame handling rules. Instead, it points to the companion ENs and the test-vector document that carry those details for design, implementation, verification, and conformance testing.

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digital cellular telecommunications system (Phase 2+) (GSM); Enhanced Full Rate (EFR) speech processing functions; General description (GSM 06.51 version 7.0.2 Release 1998)33.070.50Globalni sistem za mobilno telekomunikacijo (GSM)Global System for Mobile Communication (GSM)ICS:Ta slovenski standard je istoveten z:EN 300 723 Version 7.0.2SIST EN 300 723 V7.0.2:2003en01-december-2003SIST EN 300 723 V7.0.2:2003SLOVENSKI
STANDARD
ETSIEN300723V7.0.2(1999-12)EuropeanStandard(Telecommunicationsseries)Digitalcellulartelecommunicationssystem(Phase2+);EnhancedFullRate(EFR)speechprocessingfunctions;Generaldescription(GSM06.51version7.0.2Release1998)GLOBALSYSTEMFORMOBILECOMMUNICATIONSRSIST EN 300 723 V7.0.2:2003

ETSIETSIEN300723V7.0.2(1999-12)2(GSM06.51version7.0.2Release1998)ReferenceREN/SMG-020651Q7KeywordsDigitalcellulartelecommunicationssystem,GlobalSystemforMobilecommunications(GSM)ETSIPostaladdressF-06921SophiaAntipolisCedex-FRANCEOfficeaddress650RoutedesLucioles-SophiaAntipolisValbonne-FRANCETel.:[phone]Fax:[phone]SiretN°34862356200017-NAF742CAssociationàbutnonlucratifenregistréeàlaSous-PréfecturedeGrasse(06)N°7803/[e-mail]ETSIdeliverablecanbedownloadedfromhttp://www.etsi.orgIfyoufinderrorsinthepresentdocument,sendyourcommentto:[e-mail]Ideliverablemaybemadeavailableinmorethanoneelectronicversionorinprint.Inanycaseofexistingorperceiveddifferenceincontentsbetweensuchversions,thereferenceversionisthePortableDocumentFormat(PDF).Incaseofdispute,thereferenceshallbetheprintingonETSIprintersofthePDFversionkeptonaspecificnetworkdrivewithinETSISecretariat.CopyrightNotificationNopartmaybereproducedexceptasauthorizedbywrittenpermission.Thecopyrightandtheforegoingrestrictionextendtoreproductioninallmedia.©EuropeanTelecommunicationsStandardsInstitute1999.Allrightsreserved.SIST EN 300 723 V7.0.2:2003

ETSIETSIEN300723V7.0.2(1999-12)3(GSM06.51version7.0.2Release1998)ContentsIntellectualPropertyRights.4Foreword.41Scope.52References.53Definitionsandabbreviations.63.1Definitions.63.2Abbreviations.64General.65EnhancedFullRatespeechchanneltranscoding.86EnhancedFullRatespeechchanneldiscontinuoustransmission(DTX).87EnhancedFullRatespeechchannelVoiceActivityDetection(VAD).88EnhancedFullRatespeechchannelcomfortnoiseinsertion.99EnhancedFullRatespeechchannellostspeechframesubstitutionandmuting.910EnhancedFullRatecodechoming.9AnnexA(informative):ChangeRequestHistory.11History.12SIST EN 300 723 V7.0.2:2003

ETSIETSIEN300723V7.0.2(1999-12)4(GSM06.51version7.0.2Release1998)IntellectualPropertyRightsIPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.TheinformationpertainingtotheseessentialIPRs,ifany,ispubliclyavailableforETSImembersandnon-members,andcanbefoundinSR000314:"IntellectualPropertyRights(IPRs);Essential,orpotentiallyEssential,IPRsnotifiedtoETSIinrespectofETSIstandards",whichisavailablefromtheETSISecretariat.LatestupdatesareavailableontheETSIWebserver(http://www.etsi.org/ipr).PursuanttotheETSIIPRPolicy,noinvestigation,includingIPRsearches,hasbeencarriedoutbyETSI.NoguaranteecanbegivenastotheexistenceofotherIPRsnotreferencedinSR000314(ortheupdatesontheETSIWebserver)whichare,ormaybe,ormaybecome,essentialtothepresentdocument.ForewordThisEuropeanStandard(Telecommunicationsseries)hasbeenproducedbySpecialMobileGroup(SMG).ThepresentdocumentintroducestheEnhancedFullRate(EFR)speechtrafficchannelswithinthedigitalcellulartelecommunicationssystem.ThecontentsofthepresentdocumentissubjecttocontinuingworkwithinSMGandmaychangefollowingformalSMGapproval.ShouldSMGmodifythecontentsofthepresentdocumentitwillbere-releasedwithanidentifyingchangeofreleasedateandanincreaseinversionnumberasfollows:Version7.x.ywhere:7indicatesRelease1998ofGSMPhase2+xtheseconddigitisincrementedforallchangesofsubstance,i.e.technicalenhancements,corrections,updates,etc.ythethirddigitisincrementedwheneditorialonlychangeshavebeenincorporatedinthespecification.NationaltranspositiondatesDateofadoptionofthisEN:3December1999DateoflatestannouncementofthisEN(doa):31March2000DateoflatestpublicationofnewNationalStandardorendorsementofthisEN(dop/e):30September2000DateofwithdrawalofanyconflictingNationalStandard(dow):30September2000SIST EN 300 723 V7.0.2:2003

ETSIETSIEN300723V7.0.2(1999-12)5(GSM06.51version7.0.2Release1998)1ScopeThepresentdocumentisanintroductiontoGSM06.60[6],GSM06.61[7],GSM06.62[8],GSM06.81[9]andGSM06.82[10]ENsdealingwiththespeechprocessingfunctionsintheEnhancedFullRatechanneloftheGSMsystem.Ageneraloverviewofthespeechprocessingfunctionsisgiven,withreferencetotheENswhereeachfunctionisspecifiedindetail.2ReferencesThefollowingdocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsofthepresentdocument.•Referencesareeitherspecific(identifiedbydateofpublication,editionnumber,versionnumber,etc.)ornon-specific.•Foraspecificreference,subsequentrevisionsdonotapply.•Foranon-specificreference,thelatestversionapplies.•Anon-specificreferencetoanETSshallalsobetakentorefertolaterversionspublishedasanENwiththesamenumber.•ForthisRelease1998document,referencestoGSMdocumentsareforRelease1998versions(version7.x.y).[1]GSM01.04:"Digitalcellulartelecommunicationssystem(Phase2+);Abbreviationsandacronyms".[2]GSM03.50:"Digitalcellulartelecommunicationssystem(Phase2+);TransmissionplanningaspectsofthespeechserviceintheGSMPublicLandMobileNetwork(PLMN)system".[3]GSM05.03:"Digitalcellulartelecommunicationssystem(Phase2+);Channelcoding".[4]GSM06.53:"Digitalcellulartelecommunicationssystem(Phase2+);ANSI-CcodefortheGSMEnhancedFullRate(EFR)speechcodec".[5]GSM06.54:"Digitalcellulartelecommunicationssystem(Phase2+);TestvectorsfortheGSMEnhancedFullRate(EFR)speechcodec".[6]GSM06.60:"Digitalcellulartelecommunicationssystem(Phase2+);EnhancedFullRate(EFR)speechtranscoding".[7]GSM06.61:"Digitalcellulartelecommunicationssystem(Phase2+);SubstitutionandmutingoflostframeforEnhancedFullRate(EFR)speechtrafficchannels".[8]GSM06.62:"Digitalcellulartelecommunicationssystem(Phase2+);ComfortnoiseaspectsforEnhancedFullRate(EFR)speechtrafficchannels".[9]GSM06.81:"Digitalcellulartelecommunicationssystem(Phase2+);Discontinuoustransmission(DTX)forEnhancedFullRate(EFR)speechtrafficchannels".[10]GSM06.82:"Digitalcellulartelecommunicationssystem(Phase2+);VoiceActivityDetector(VAD)forEnhancedFullRate(EFR)speechtrafficchannels".SIST EN 300 723 V7.0.2:2003

ETSIETSIEN300723V7.0.2(1999-12)6(GSM06.51version7.0.2Release1998)3Definitionsandabbreviations3.1DefinitionsDefinitionoftermsusedinthepresentdocumentcanbefoundinGSM06.60[6],GSM06.61[7],GSM06.62[8],GSM06.81[9]andGSM06.82[10].3.2AbbreviationsForthepurposesofthepresentdocument,thefollowingabbreviationsapply:ACELPAlgebraicCodeExcitedLinearPredictionBFIBadFrameIndicationBSSBaseStationSystemCCITTComitéConsultatifInternationalTélégraphiqueetTéléphoniqueDTXDiscontinuousTransmissionETSEuropeanTelecommunicationStandardGSMGlobalSystemforMobilecommunicationsMSMobileStationPCMPulseCodeModulatedPLMNPublicLandMobileNetw
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