ITU-T G.113 (11 2007) (英) Transmission impairments

InternationalTelecommunicationUnionITU-TG.113TELECOMMUNICATIONSTANDARDIZATIONSECTOROFITU(11/2007)SERIESG:TRANSMISSIONSYSTEMSANDMEDIA,DIGITALSYSTEMSANDNETWORKSInternationaltelephoneconnectionsandcircuits–GeneralRecommendationsonthetransmissionqualityforanentireinternationaltelephoneconnectionTransmissionimpairmentsduetospeechprocessingITU-TRecommendationG.113ITU-TG-SERIESRECOMMENDATIONSTRANSMISSIONSYSTEMSANDMEDIA,DIGITALSYSTEMSANDNETWORKSINTERNATIONALTELEPHONECONNECTIONSANDCIRCUITSG.100–G.199GeneraldefinitionsG.100–G.109GeneralRecommendationsonthetransmissionqualityforanentireinternationaltelephoneconnectionG.110–G.119GeneralcharacteristicsofnationalsystemsformingpartofinternationalconnectionsG.120–G.129Generalcharacteristicsofthe4-wirechainformedbytheinternationalcircuitsandnationalextensioncircuitsG.130–G.139Generalcharacteristicsofthe4-wirechainofinternationalcircuits;internationaltransitG.140–G.149GeneralcharacteristicsofinternationaltelephonecircuitsandnationalextensioncircuitsG.150–G.159Apparatusassociatedwithlong-distancetelephonecircuitsG.160–G.169TransmissionplanaspectsofspecialcircuitsandconnectionsusingtheinternationaltelephoneconnectionnetworkG.170–G.179ProtectionandrestorationoftransmissionsystemsG.180–G.189SoftwaretoolsfortransmissionsystemsG.190–G.199GENERALCHARACTERISTICSCOMMONTOALLANALOGUECARRIER-TRANSMISSIONSYSTEMSG.200–G.299INDIVIDUALCHARACTERISTICSOFINTERNATIONALCARRIERTELEPHONESYSTEMSONMETALLICLINESG.300–G.399GENERALCHARACTERISTICSOFINTERNATIONALCARRIERTELEPHONESYSTEMSONRADIO-RELAYORSATELLITELINKSANDINTERCONNECTIONWITHMETALLICLINESG.400–G.449COORDINATIONOFRADIOTELEPHONYANDLINETELEPHONYG.450–G.499TRANSMISSIONMEDIAANDOPTICALSYSTEMSCHARACTERISTICSG.600–G.699DIGITALTERMINALEQUIPMENTSG.700–G.799DIGITALNETWORKSG.800–G.899DIGITALSECTIONSANDDIGITALLINESYSTEMG.900–G.999QUALITYOFSERVICEANDPERFORMANCE–GENERICANDUSER-RELATEDASPECTSG.1000–G.1999TRANSMISSIONMEDIACHARACTERISTICSG.6000–G.6999DATAOVERTRANSPORT–GENERICASPECTSG.7000–G.7999PACKETOVERTRANSPORTASPECTSG.8000–G.8999ACCESSNETWORKSG.9000–G.9999Forfurtherdetails,pleaserefertothelistofITU-TRecommendations.ITU-TRec.G.113(11/2007)iITU-TRecommendationG.113TransmissionimpairmentsduetospeechprocessingSummaryITU-TRecommendationG.113providesguidanceregardingtransmissionimpairmentsintroducedbydigitalspeechprocessingsystems.TheinformationprovidedisforuseinconjunctionwiththetransmissionplanningapproachdescribedinITU-TRecommendationsG.107,G.108andG.109.Theimpairmentfactormethod,usedbytheE-modelofITU-TRecommendationG.107,isnowrecommended.Theearliermethodthatusedquantizationdistortionunitsisnolongerrecommended.UpdatedimpairmentfactorvaluesforvariousdigitalprocessingsystemsareprovidedinAppendixI.AppendixIIcontainsguidanceonhowanadvantagefactorcanbeusedtoreflectthevariationinuserexpectationofqualityfordifferentcommunicationssystems(e.g.,mobile).AppendixIIIprovidesguidelinesregardingindividualtransmissionimpairmentparametersotherthanqduandequipmentimpairmentfactor,andAppendixIVgivesprovisionalplanningvaluesforthewidebandequipmentimpairmentfactor.SourceITU-TRecommendationG.113wasapprovedon13November2007byITU-TStudyGroup12(2005-2008)undertheITU-TRecommendationA.8procedure.iiITU-TRec.G.113(11/2007)FOREWORDTheInternationalTelecommunicationUnion(ITU)istheUnitedNationsspecializedagencyinthefieldoftelecommunications,informationandcommunicationtechnologies(ICTs).TheITUTelecommunicationStandardizationSector(ITU-T)isapermanentorganofITU.ITU-Tisresponsibleforstudyingtechnical,operatingandtariffquestionsandissuingRecommendationsonthemwithaviewtostandardizingtelecommunicationsonaworldwidebasis.TheWorldTelecommunicationStandardizationAssembly(WTSA),whichmeetseveryfouryears,establishesthetopicsforstudybytheITU-Tstudygroupswhich,inturn,produceRecommendationsonthesetopics.TheapprovalofITU-TRecommendationsiscoveredbytheprocedurelaiddowninWTSAResolution1.InsomeareasofinformationtechnologywhichfallwithinITU-T'spurview,thenecessarystandardsarepreparedonacollaborativebasiswithISOandIEC.NOTEInthisRecommendation,theexpressionAdministrationisusedforconcisenesstoindicatebothatelecommunicationadministrationandarecognizedoperatingagency.CompliancewiththisRecommendationisvoluntary.However,theRecommendationmaycontaincertainmandatoryprovisions(toensuree.g.,interoperabilityorapplicability)andcompliancewiththeRecommendationisachievedwhenallofthesemandatoryprovisionsaremet.Thewordsshallorsomeotherobligatorylanguagesuchasmustandthenegativeequivalentsareusedtoexpressrequirements.TheuseofsuchwordsdoesnotsuggestthatcompliancewiththeRecommendationisrequiredofanyparty.INTELLECTUALPROPERTYRIGHTSITUdrawsattentiontothepossibilitythatthepracticeorimplementationofthisRecommendationmayinvolvetheuseofaclaimedIntellectualPropertyRight.ITUtakesnopositionconcerningtheevidence,validityorapplicabilityofclaimedIntellectualPropertyRights,whetherassertedbyITUmembersorothersoutsideoftheRecommendationdevelopmentprocess.AsofthedateofapprovalofthisRecommendation,ITUhadreceivednoticeofintellectualproperty,protectedbypatent