SIST EN 301 790 V1.2.2:2003

• Abstract:

  Return chanel speciufication for satellite applications

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.070.40 - Satellite
• ICS: 33.170 - Television and radio broadcasting
• 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 301 790 V1.2.2 (2000-12) - Digital Video Broadcasting (DVB); Interaction channel for satellite distribution systems

Overview

SIST EN 301 790 V1.2.2:2003 is the Slovenian standard that specifies the requirements for the interaction channel in satellite distribution systems used for Digital Video Broadcasting (DVB). Developed in alignment with European Standard EN 301 790, this document provides a comprehensive baseline for enabling return channels in satellite broadcasting, facilitating interactive television services over geostationary (GEO) satellite networks. The standard is especially focused on fixed return channel satellite terminals (RCSTs), supporting both individual and collective installations, such as Satellite Master Antenna Television (SMATV) systems, and integration with in-home data networks.

Key Topics

SIST EN 301 790 V1.2.2:2003 addresses the following main areas:

• Reference Models for DVB Satellite Interactive Networks: Specifies protocols, system elements, and the conceptual architecture for integrating interactive capabilities into satellite broadcasting networks.
• Return Channel Specification: Details the technical requirements for the physical and signaling layers supporting upstream (user-to-network) communication, enabling interactive services such as requests, responses, and data transfers.
• Synchronization and Multiple Access Control: Defines synchronization procedures, medium access methods (including Multiple-Frequency Time-Division Multiple Access, MF-TDMA), and capacity reservation protocols to ensure reliable network operation.
• Security and Authentication: Provides guidelines for secure data transmission, including authentication, encryption options, and key management, to maintain communication integrity and confidentiality.
• Integration with Broadcast Channels: Describes operational models for combining unidirectional broadcast channels (network-to-user) and bidirectional interaction channels, supporting diverse DVB services and applications.

Applications

The return channel defined in SIST EN 301 790 V1.2.2:2003 expands the possibilities of satellite broadcasting by enabling interactive and two-way communication between end users and service providers. Key practical applications include:

• Interactive Television (iTV): Viewers can participate in live polls, quizzes, or e-commerce directly through their TV using the return channel.
• Software and Data Downloads: Enables distribution of software updates, multimedia content, or digital services on demand, using secure upstream requests.
• Home Networking: Supports connectivity between satellite receivers and in-home networks, allowing seamless sharing of interactive DVB services.
• Professional and Commercial Services: Facilitates services such as pay-per-view events, remote education, telemedicine, e-banking, and other interactive applications by providing a secure, reliable upstream communication path.
• Collective Installations: SMATV systems, commonly used in apartment complexes or community buildings, benefit from standardized return channel integration, ensuring compatibility and efficiency.

Related Standards

SIST EN 301 790 V1.2.2:2003 is closely related to several other international DVB and satellite communication standards. Key references include:

• EN 300 421: DVB framing, channel coding, and modulation for 11/12 GHz satellite services.
• EN 300 468: Specification for Service Information (SI) in DVB systems.
• EN 301 192: DVB specification for data broadcasting.
• EN 301 459: Harmonized standard for Satellite Interactive Terminals (SIT) and User Terminals (SUT) in GEO orbit.
• EN 300 802: Network-independent protocols for DVB interactive services.
• ETSI ES 200 800: DVB interaction channel for Cable TV (CATV) systems.

By adhering to SIST EN 301 790 V1.2.2:2003, satellite network operators, set-top box manufacturers, and service providers ensure interoperability, security, and scalability in deploying interactive DVB solutions, supporting expanding demands for interactivity in satellite broadcasting environments.

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digitalna videoradiodifuzija (DVB) – Povratni kanal za satelitske distribucijske sistemeDigital Video Broadcasting (DVB); Interaction channel for satellite distribution systems33.170Televizijska in radijska difuzijaTelevision and radio broadcasting33.070.40SatelitSatelliteICS:Ta slovenski standard je istoveten z:EN 301 790 Version 1.2.2SIST EN 301 790 V1.2.2:2003en01-december-2003SIST EN 301 790 V1.2.2:2003SLOVENSKI
STANDARD
ETSIEN301790V1.2.2(2000-12)EuropeanStandard(Telecommunicationsseries)DigitalVideoBroadcasting(DVB);Interactionchannelforsatellitedistributionsystems;EuropeanBroadcastingUnionUnionEuropéennedeRadio-TélévisionEBU·UERSIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)2ReferenceDEN/JTC-DVB-96Keywordsbroadcasting,DVB,interaction,satelliteETSI650RoutedesLuciolesF-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.©EuropeanTelecommunicationsStandardsInstitute2000.©EuropeanBroadcastingUnion2000.Allrightsreserved.SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)3ContentsIntellectualPropertyRights.7Foreword.71Scope.82References.83Definitions,symbolsandabbreviations.93.1Definitions.93.2Symbols.93.3Abbreviations.94ReferenceModelsforSatelliteInteractiveNetworksinDVB.114.1ProtocolStackModel.114.2SystemModel.124.3ReferenceModeloftheSatelliteInteractiveNetwork.135ForwardLink.146ReturnLinkBase-bandPhysicalLayerSpecificationandMultipleAccessDefinition.146.1RCSTsynchronization.156.1.1TimingControl.156.1.2Carriersynchronization.156.1.3Burstsynchronization.156.1.4Symbolclocksynchronization.166.2BurstFormat.166.2.1Traffic(TRF)burstformats.166.2.1.1ATMTRFburst.166.2.1.2OptionalMPEG2-TSTRFburst.166.2.2Synchronizationandacquisitionburstformats.176.2.2.1Synchronization(SYNC)burstformat.176.2.2.2Acquisition(ACQ)burst.176.2.3CommonSignallingChannel(CSC)burstformat.186.2.4BitNumberingandInterpretation.196.2.5TransmissionOrder.196.3Randomizationforenergydispersal.196.4Coding.206.4.1CRCerrordetectioncode.206.4.2ReedSolomonoutercoding.206.4.3Convolutionalinnercoding.206.4.4Turbocode.216.4.4.1Descriptionoftheturbocodepermutation.226.4.4.2Determinationofthecirculationstates.236.4.4.3Ratesandpuncturingmap.236.4.4.4OrderoftransmissionandmappingtoQPSKconstellation.246.5Modulation.256.5.1BitmappingtoQPSKconstellation.256.5.2Basebandshapingandquadraturemodulation.256.5.3Outputpowercontrol.266.5.4GuardTime.266.6MACmessages.266.6.1PrefixMethod.266.6.1.1Prefixmethodmechanism.266.6.1.2SatelliteAccessControl(SAC)field.266.6.2Dataunitlabellingmethod(DULM).276.6.2.1DULMwithATM-formatting.276.6.2.2DULMwithMPEG-formatting.296.6.3Mini-slotMethod.306.6.4ContentionbasedMini-slotMethod.30SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)46.7MultipleAccess.306.7.1MF-TDMA.306.7.1.1FixedMF-TDMA.306.7.1.2DynamicMF-TDMA(Optional).316.7.1.3Frequencyrange.316.7.2Segmentationofthereturnlinkcapacity.326.7.2.1Superframes.326.7.2.2Frames.336.7.2.3Timeslots.336.8Capacityrequestcategories.346.8.1ContinuousRateAssignment(CRA).346.8.2RateBasedDynamicCapacity(RBDC).346.8.3VolumeBasedDynamicCapacity(VBDC).346.8.4AbsoluteVolumeBasedDynamicCapacity(AVBDC).346.8.5FreeCapacityAssignment(FCA).347Synchronizationprocedures.357.1OverallEventsSequencing.357.2Initialsynchronizationprocedure.377.3Logonprocedure.387.4Coarsesynchronizationprocedure(Optional).387.5FineSynchronizationProcedure(Optional).397.6SynchronizationMaintenanceprocedure.407.7LogoffProcedure.417.7.1General.417.7.2Normal.417.7.3Abnormal.418Controlandmanagement.418.1Protocolstack.418.1.1RCSTTypeA(IP).418.1.2OptionalRCSTTypeB(NativeATM).438.2RCSTAddressing.448.3ForwardLinkSignalling.448.3.1GeneralSITables.448.3.1.1SuperframeCompositionTable(SCT).448.3.1.2FrameCompositionTable(FCT).448.3.1.3Time-SlotCompositionTable(TCT).458.3.1.4SatellitePositionTable(SPT).458.3.1.5CorrectionMessageTable(CMT).458.3.1.6TerminalBurstTimePlan(TBTP).458.3.2TerminalInformationMessage(TIM).458.3.3PCRInsertionTSPacket.458.3.4Summary.458.3.5RepetitionRates.468.4ReturnLinkSignalling.468.4.1RCSTsynchronizationandIdentificationmessages.468.4.2ConfigurationparametersbetweenRCSTandNCC(optional).478.4.3OtherMessagesforNetworkManagement(optional).478.4.4BurstTimePlanExchange.488.5CodingofSIforForwardLinkSignalling.488.5.1Introduction.488.5.2SITableMechanism.488.5.3DSM-CCSectionMechanism.488.5.4CodingofPIDandtable_idfields.498.5.5Tabledefinitions.498.5.5.1StandardSectionHeaders.498.5.5.1.1SISectionHeader.508.5.5.1.2DSM-CCPrivateSectionHeader.518.5.5.2SuperframeCompositionTable(SCT).528.5.5.3FrameCompositionTable(FCT).548.5.5.4TimeslotCompositionTable(TCT).55SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)58.5.5.5SatellitePositionTable(SPT).588.5.5.6PCRInsertionTransportStreampacket.588.5.5.6.1TSpacketformat.588.5.5.6.2Adaptationfield.598.5.5.6.3OptionalPayloadfield.598.5.5.7TerminalBurstTimePlan(TBTP).608.5.5.8TerminalInformationMessage(TIM).628.5.5.9CorrectionMessageTable(CMT).648.5.5.10Descriptorcoding.668.5.5.10.1DescriptorIdentificationandlocation.668.5.5.10.2NetworkLayerInfoDescriptor(optional).668.5.5.10.3CorrectionMessagedescriptor.678.5.5.10.4LogonInitializeDescriptor.688.5.5.10.5ACQAssignDescriptor.708.5.5.10.6SYNCAssignDescriptor.718.5.5.10.7EncryptedLogonIDDescriptor.728.5.5.10.8EchoValueDescriptor.728.5.5.10.9Linkagedescriptor(privatedata).738.5.5.10.10RCScontentdescriptor.748.5.5.10.11Satelliteforwardlinkdescriptor.758.5.5.10.12Satellitereturnlinkdescriptor.778.5.5.10.13TableUpdateDescriptor.788.5.5.10.14Contentioncontroldescriptor.798.5.5.10.15CorrectionControldescriptor.798.5.5.11Accessingoftheforwardlinksignalling.809Security,Identity,Encryption.849.1Authentication.849.2ForwardLink.849.3ReturnLink.859.4Security(optional).859.4.1Cryptographicprimitives.859.4.1.1Publickeyexchange.869.4.1.2Hashing.869.4.1.3Encryption.869.4.1.4Pseudo-randomnumbers.879.4.2MainKeyExchange,MKE.879.4.3QuickKeyExchange,QKE.889.4.4ExplicitKeyExchange,EKE.889.4.5Keyderivation.889.4.6Datastreamprocessing.889.4.6.1Payloadstreams.899.4.6.2Dataencryption.899.4.6.3Encryptionflags.899.4.6.4Chainingandinitializationvector.909.4.7SecurityEstablishment.909.4.8Persistentstatevariables.919.4.8.1Guaranteeddelivery.919.4.9SecurityMACMessages.919.4.9.1SecuritySign-On.919.4.9.2SecuritySign-OnResponse.929.4.9.3MainKeyExchange.939.4.9.4MainKeyExchangeResponse.939.4.9.5QuickKeyExchange.949.4.9.6QuickKeyExchangeResponse.949.4.9.7ExplicitKeyExchange.959.4.9.8ExplicitKeyExchangeResponse.959.4.9.9Wait.96SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)6AnnexA(informative):Compliancetable.97Bibliography.98History.99SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)7IntellectualPropertyRightsIPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.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)hasbeenproducedbyJointTechnicalCommittee(JTC)oftheEuropeanBroadcastingUnion(EBU),ComitéEuropéendeNormalisationElectrotechnique(CENELEC)andtheEuropeanTelecommunicationsStandardsInstitute(ETSI).NOTE:TheEBU/ETSIJTCBroadcastwasestablishedin1990toco-ordinatethedraftingofstandardsinthespecificfieldofbroadcastingandrelatedfields.Since1995theJTCBroadcastbecameatripartitebodybyincludingintheMemorandumofUnderstandingalsoCENELEC,whichisresponsibleforthestandardizationofradioandtelevisionreceivers.TheEBUisaprofessionalassociationofbroadcastingorganizationswhoseworkincludestheco-ordinationofitsmembers'activitiesinthetechnical,legal,programme-makingandprogramme-exchangedomains.TheEBUhasactivemembersinabout60countriesintheEuropeanbroadcastingarea;itsheadquartersisinGeneva.EuropeanBroadcastingUnionCH-1218GRANDSACONNEX(Geneva)SwitzerlandTel:[phone]Fax:[phone]FoundedinSeptember1993,theDVBProjectisamarket-ledconsortiumofpublicandprivatesectororganizationsinthetelevisionindustry.ItsaimistoestablishtheframeworkfortheintroductionofMPEG-2baseddigitaltelevisionservices.Nowcomprisingover200organizationsfrommorethan25countriesaroundtheworld,DVBfostersmarket-ledsystems,whichmeettherealneeds,andeconomiccircumstances,oftheconsumerelectronicsandthebroadcastindustry.NationaltranspositiondatesDateofadoptionofthisEN:24November2000DateoflatestannouncementofthisEN(doa):28February2001DateoflatestpublicationofnewNationalStandardorendorsementofthisEN(dop/e):31August2001DateofwithdrawalofanyconflictingNationalStandard(dow):31August2001SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)81ScopeThepresentdocumentisthebaselinespecificationfortheprovisionoftheinteractionchannelforGEOsatelliteinteractivenetworkswithfixedreturnchannelsatelliteterminals(RCST).ThepresentdocumentfacilitatestheuseofRCSTsforindividualorcollectiveinstallation(e.g.SMATV)inadomesticenvironment.Italsosupportstheconnectionofsuchterminalswithin-housedatanetworks.ThepresentdocumentmaybeappliedtoallfrequencybandsallocatedtoGEOsatelliteservices.ThesolutionsprovidedinthepresentdocumentforinteractionchannelforsatelliteinteractivenetworksareapartofawidersetofalternativestoimplementinteractiveservicesforDigitalVideoBroadcasting(DVB)systems.2ReferencesThefollowingdocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsofthepresentdocument.• Referencesareeitherspecific(identifiedbydateofpublication,editionnumber,versionnumber,etc.)ornon-specific.• Foraspecificreference,subsequentrevisionsdonotapply.• Foranon-specificreference,thelatestversionapplies.• Anon-specificreferencetoanETSshallalsobetakentorefertolaterversionspublishedasanENwiththesamenumber.[1]ETSIEN300421:"DigitalVideoBroadcasting(DVB);Framingstructure,channelcodingandmodulationfor11/12GHzsatelliteservices".[2]ETSITR101202:"DigitalVideoBroadcasting(DVB);ImplementationguidelinesforDataBroadcasting".[3]ETSIETS300802:"DigitalVideoBroadcasting(DVB);Network-independentprotocolsforDVBinteractiveservices".[4]ETSIEN300468:"DigitalVideoBroadcasting(DVB);SpecificationforServiceInformation(SI)inDVBsystems".[5]ETSIEN301192:"DigitalVideoBroadcasting(DVB);DVBspecificationfordatabroadcasting".[6]ETSIEN301459:"SatelliteEarthStationsandSystems(SES);HarmonizedENforSatelliteInteractiveTerminals(SIT)andSatelliteUserTerminals(SUT)transmittingtowardssatellitesingeostationaryorbitinthe29,5GHzto30GHzfrequencybandscoveringessentialrequirementsunderarticle3.2oftheR&TTEDirective".[7]IETFRFC1483(1993):"MultiprotocolEncapsulationoverATMAdaptationLayer5".[8]ETSITR100815:"DigitalVideoBroadcasting(DVB);GuidelinesforthehandlingofAsynchronousTransferMode(ATM)signalsinDVBsystems".[9]ISO/IEC13818-1(1996):"Informationtechnology-Genericcodingofmovingpicturesandassociatedaudioinformation;Part1:Systems".[10]ETSIETR154:"DigitalVideoBroadcasting(DVB);ImplementationguidelinesfortheuseofMPEG-2Systems,VideoandAudioinsatellite,cableandterrestrialbroadcastingapplications".[11]ITU-TRecommendationQ.2931(1995):"BroadbandIntegratedServicesDigitalNetwork(B-ISDN)-DigitalSubscriberSignallingSystemNo.2(DSS2)-User-NetworkInterface(UNI)-Layer3specificationforbasiccall/connectioncontrol".SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)9[12]IEEE802.3(1996):"Informationtechnology-Telecommunicationsandinformationexchangebetweensystems-Localandmetropolitanareanetworks-Specificrequirements-Part3:Carriersensemultipleaccesswithcollisiondetection(CSMA/CD)accessmethodandphysicallayerspecifications".[13]ITU-TRecommendationI.432(1999):"B-ISDNuser-networkinterface-Physicallayerspecification".[14]ETSIES200800:"DigitalVideoBroadcasting(DVB);DVBinteractionchannelforCableTVdistributionSystem(CATV);DVBdocumentA023Rev.1,June1999.[15]IETFRFC2104(1997):"HMAC:Keyed-HashingforMessageAuthentication".[16]ANSI/IEEE754(1985):"IEEEStandardforBinaryFloating-PointArithmetic".[17]ISO/IEC13818-6(1998):"Informationtechnology-Genericcodingofmovingpicturesandassociatedaudioinformation-Part6:ExtensionsforDSM-CC".[18]ITU-TRecommendationI.363-5(1996):"B-ISDNATMAdaptationLayerspecification:Type5AAL".3Definitions,symbolsandabbreviations3.1DefinitionsForthepurposesofthepresentdocument,thefollowingtermanddefinitionapplies:reserved:term"reserved",whenusedintheclausesdefiningthecodedbitstream,indicatesthatthevaluemaybeusedforfutureextensions.Unlessotherwisespecifiedwithinthepresentdocument,allreservedbitsshallbesetto'1'.3.2SymbolsForthepurposesofthepresentdocument,thefollowingsymbolsapply:*multiplication^power~concatenationmodmodulodivision(unsignedchar)xANSICcastoperator:convertsvaluextounsignedchar""emptystring(zerolength)nonce1randomstring(NCC)nonce2randomstring(RCST)NatmNumberofATMcellsinanATMTRFburst(1,2or4).NmpegNumberofMPEGpacketsinanoptionalMPEG2-TSTRFburst(1and2*nforn=1to12).Np,atmNumberofbytesoftheprefixusedonATMTRFbursts(0,2or4).Np,syncNumberofbytesoftheoptionalprefixusedonSYNCbursts:0,2…31forconcatenatedcode,0,12or16fortheTurbocode(seesubclause6.4).3.3AbbreviationsForthepurposesofthepresentdocument,thefollowingabbreviationsapply:AALATMAdaptationLayerACQAcquisitionburstATMAsynchronousTransferModeAVBDCAbsoluteVolume-BasedDynamicCapacityBCDBinaryCodedDecimalBTPBurstTimePlanCBCCipherBlockChainingSIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)10CMFControl&MonitoringFunctionsCMTCorrectionMessageTableCRCapacityRequestsCRAConstant-RateAssignmentCRCCyclicRedundancyCheckCRSCCircularRecursiveSystematicConvolutionalCSCCommonSignallingChannelCTRL/MNGMControl/ManagementvirtualchannelusedinDULMDESDataEncryptionStandardDSM-CCDigitalStorageMedium-CommandandControlDULMDataUnitLabellingMethodDVBDigitalVideoBroadcastDVB-SDigitalVideoBroadcastbySatelliteEKEExplicitKeyExchangeENEuropeanNormETSEuropeanTelecommunicationsStandardETSIEuropeanTelecommunicationsStandardsInstituteFCAFreeCapacityAssignmentFCTFrameCompositionTableFLSForwardLinkSignallingGEOGeostationaryEarthOrbitGFCGenericFlowControlHMACHash-basedMessageAuthenticationCodeHPAHighPowerAmplifierIIn-phaseIDIdentifierIDUIndoorunitIEInformationElementIECInternationalElectrotechnicalCommissionIEEEInstituteofElectricalandElectronicsEngineersIFIntermediateFrequencyIPInternetProtocolISDNIntegratedServicesDigitalNetworkISOInternationalStandardsOrganizationITUInternationalTelecommunicationUnionIVInitializationVectorLFSRLinearFeedbackShiftRegisterLLCLogicalLinkControlLSBLeastSignificantBitM&CMonitoringandControlMACMediumAccessControlMF-TDMAMultiple-FrequencyTime-DivisionMultipleAccessMIBManagementInformationBaseMKEMainKeyExchangeMPEGMovingPictureExpertsGroupMSBMostSignificantbitNCCNetworkControlCentreNCRNetworkClockReferenceNITNetworkInformationTableNIUNetworkInterfaceUnitOBOOutputBack-OffODUOutdoorunitOSIOpenSystemsInterconnectionPATProgramAssociationTablePCPersonalComputerPCRProgramClockReferencePIDPacketIDentifierPMTProgramMapTableppmpartspermillionPRBSPseudoRandomBinarySequencePRNGPseudo-RandomNumberGeneratorPSIProgramSpecificInformationSIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)11PSTNPublicSwitchedTelephoneNetworkPVCPermanentVirtualCircuitQQuadratureQKEQuickKeyExchangeQPSKQuadraturePhase-ShiftKeyingRBDCRate-BasedDynamicCapacityRCSTReturnChannelSatelliteTerminalRFRadioFrequencyRMTRCSMapTableRSReed-SolomonSACSatelliteAccessControlSARSegmentationAndRe-assemblySCTSuperframeCompositionTableSDTServiceDescriptionTableSIServiceInformationSITSatelliteInteractiveTerminalSMATVSatelliteMasterAntennaTelevisionSNAPSubNetworkAccessProtocolSNMPSimpleNetworkManagementProtocolSPTSatellitePositionTableSUTSatelliteUserTerminalSVCSwitchedVirtualCircuitSYNCSynchronizationbursttypeTBTPTerminalBurstTimePlanTCTTime-slotCompositionTableTDMATime-DivisionMultipleAccessTGTrafficGatewayTIMTerminalInformationMessageTRFTraffic(bursttype)TSTransportStreamTxTransmitterUNIUserNetworkInterfaceVBDCVolume-BasedDynamicCapacityVCIVirtualCircuitIdentifierVPIVirtualPathIdentifier4ReferenceModelsforSatelliteInteractiveNetworksinDVB4.1ProtocolStackModelForinteractiveservicessupportingbroadcasttotheenduserwithreturnchannel,asimplecommunicationsmodelconsistsofthefollowinglayers:physicallayer:whereallthephysical(electrical)transmissionparametersaredefined.transportlayer:definesalltherelevantdatastructuresandcommunicationprotocolslikedatacontainers,etc.applicationlayer:istheinteractiveapplicationsoftwareandruntimeenvironment(e.g.homeshoppingapplication,scriptinterpreter,etc.).AsimplifiedmodeloftheOSIlayerswasadoptedtofacilitatetheproductionofspecificationsfortheselayers.Figure1pointsoutthelowerlayersofthesimplifiedmodelandidentifiessomeofthekeyparametersforthelowertwolayers.SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)12AccessmechanismPacketstructureHighermediumlayersProprietarylayersNetworkDependentProtocolsNetworkIndependentProtocolsSynchronizationModulationChannelcodingFreq.RangeFilteringPowerFigure1:LayerstructureforgenericsystemreferencemodelThepresentdocumentaddressesthesatelliteinteractivenetworkdependentaspectsonly.4.2SystemModelFigure2showsthesystemmodelwhichistobeusedwithinDVBforinteractiveservices.Inthesystemmodel,twochannelsareestablishedbetweentheserviceproviderandtheuser:-BroadcastChannel:aunidirectionalbroadbandBroadcastChannelincludingvideo,audioanddataisestablishedfromtheserviceprovidertotheusers.ItmayincludetheForwardInteractionPath.-InteractionChannel:abi-directionalInteractionChannelisestablishedbetweentheserviceproviderandtheuserforinteractionpurposes.Itisformedby:-ReturnInteractionPath(ReturnChannel):fromtheusertotheserviceprovider.Itisusedtomakerequeststotheserviceprovider,toanswerquestionsortotransferdata.-ForwardInteractionPath:fromtheserviceprovidertotheuser.Itisusedtoprovideinformationfromtheserviceprovidertotheuserandanyotherrequiredcommunicationfortheinteractiveserviceprovision.ItmaybeembeddedintotheBroadcastChannel.ItispossiblethatthischannelisnotrequiredinsomesimpleimplementationswhichmakeuseoftheBroadcastChannelforthecarriageofdatatotheuser.TheRCSTisformedbytheNetworkInterfaceUnit(consistingoftheBroadcastInterfaceModuleandtheInteractiveInterfaceModule)andtheSetTopUnit.TheRCSTprovidesinterfaceforbothBroadcastandInteractionChannels.TheinterfacebetweentheRCSTandtheinteractionnetworkisviatheInteractiveInterfaceModule.SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)13ReturnChannelSatelliteTerminal(RCST)Figure2:AgenericsystemReferenceModelforInteractiveSystems4.3ReferenceModeloftheSatelliteInteractiveNetworkAnoverallSatelliteInteractiveNetwork,withinwhichalargenumberofReturnChannelSatelliteTerminal(RCST)willoperate,willcomprisethefollowingfunctionalblocks,asshowninfigure3:-NetworkControlCentre:aNCCprovidesmonitoring&controlfunctions.ItgeneratescontrolandtimingsignalsfortheoperationoftheSatelliteInteractiveNetworktobetransmittedbyoneorseveralFeederStations.-TrafficGateway:aTGreceivestheRCSTreturnsignals,providesaccountingfunctions,interactiveservicesand/orconnectionstoexternalpublic,proprietaryandprivateserviceproviders(databases,pay-per-viewTVorvideosources,softwaredownload,tele-shopping,tele-banking,financialservices,stockmarketaccess,interactivegamesetc.)andnetworks(Internet,ISDN,PSTNetc…).-Feeder:aFeedertransmitstheforwardlinksignal,whichisastandardsatellitedigitalvideobroadcast(DVB-S)uplink,ontowhicharemultiplexedtheuserdataand/orthecontrolandtimingsignalsneededfortheoperationoftheSatelliteInteractiveNetwork.AnRCSTise.g.aSIToraSUTasdescribedin[6].SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)14RCSTNCCSATFWSATRTRCSTNETWORK1NETWORK2InteractiveNetworkAdapterFEEDER1STATIONGATEWAY1STATIONDVBForwardLink1DVBForwardLink2RCSTReturnLinkRCSTRCSTGATEWAY2STATIONFEEDER2STATIONBroadcastNetworkAdapterInteractiveServiceProviderBroadcastServiceProviderFigure3:ReferenceModelfortheSatelliteInteractiveNetworkTheforwardlinkcarriessignallingfromtheNCCandusertraffictoRCSTs.ThesignallingfromtheNCCtoRCSTsthatisnecessarytooperatethereturnlinksystemiscalled"ForwardLinkSignalling"inthefollowing.Boththeusertrafficandforwardlinksignallingcanbecarriedoverdifferentforwardlinksignals.SeveralRCSTconfigurationsarepossibledependingonthenumberofforwardlinkreceiverspresentontheRCST.5ForwardLinkTheRCSTshallbeabletoreceivedigitalsignalsconformingtoEN300421[1],TR101202[2],ETS300802[3],EN300468[4],EN301192[5]andETR154[10].6ReturnLinkBase-bandPhysicalLayerSpecificationandMultipleAccessDefinitionSpecificationsforthebase-bandphysicallayeraregiveninthischapter.Figure4representsthegenericdigitalsignalprocessingtobeperformedattheRCSTtransmitterside,fromtheburstformattingoftheserialinformationbit-stream,tothemodulationrepresentingthedigitaltoanalogueconversion.Thesignalprocessingtobeperformedbyeachsubsetisdescribedinthefollowingsections.SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)15EnergyDispersalInformationdataMACdataChannelCodingBurstformattingI/QburstmodulationModulatedsignalSynchronizationFigure4:BlockdiagramoftheRCSTreturnlinkbasebandsignalprocessing6.1RCSTsynchronization6.1.1TimingControlThesynchronizationoftheRCSTisanimportantfeatureofthesatelliteinteractivenetwork.ConstraintsareimposedontheRCSTstoobtainanefficientTDMAsystemwithminimuminterferencebetweenusersandmaximumthroughput,althoughtheycanbeminimizediftheNCCperformstaskssuchassatellitefrequencytranslationerrorandcommon-modeDopplercompensationforRCSTcarrierfrequency.Forthisreason,thesynchronizationschemeisbasedoninformationcontainedwithintheForwardLinkSignallingasfollows:-NCR(NetworkClockReference);-signallinginDVB/MPEG2-TSprivatesections.TheNCRisdistributedwithaspecificPIDwithintheMPEG2TransportStreamthatcarriestheForwardLinkSignalling.TheNCRdistributionfollowsthePCRdistributionmechanismasdefinedinISO/IEC13818-1[9],whichisusuallyderivedfromanMPEGvideoencoder,whereasheretheNCRisderivedfromtheNCCreferenceclock.TheNCCreferenceclockwillhaveanaccuracyof5ppmorbetter.6.1.2CarriersynchronizationTheMPEG2-TSthatcarriestheForwardLinkSignallingcontainsaNCRinformationwhichprovidesa27MHzreferenceoftheNCCreferenceclocktotheRCSTs.TheRCSTreconstructsthereferenceclockfromthereceivedNCRinformationasimplementedinMPEGdecodersforMPEG2TransportStreams(MPEG2-TS).TheRCSTthenperformsacomparisontodeterminetheoffsetbetweenthelocalreferenceclockwhichcontrolstheRCSTupconverterlocaloscillatorandthereferenceclockrecoveredfromthereceivedNCR.Itthencompensatesthecarrierfrequencyaccordingtothisoffset.ThislocalcarriersynchronizationprovidesawayofadjustingthetransmitfrequencyofallRCSTsonthenetworktoalmostthesamefrequency.Normalizedcarrierfrequencyaccuracyshallbebetterthan10-8(rootmeansquare).6.1.3BurstsynchronizationTheRCSTsretrievethecentrefrequency,thestarttimeandthedurationoftheirtransmitburstsbyexaminingtheforwardlinksignalling(morepreciselytheSCT,FCTandTCTtablesdescribedinsubclause8.3.1).ThecontentionbetweenRCSTsonthereturnlinkisresolvedasdescribedinsubclause6.7.TheburstsaresentaccordingtotheBurstTimePlan(BTP)receivedintheForwardLinkSignalling(seesubclause6.7.2).TheBTPisexpressedintermsofcentrefrequencyandabsolutestarttime(giveninNCR-countervalue)ofsuperframesandassociatedfrequencyandtimeoffsetsofburstallocationsalongwithadescriptionofthetimeslotproperties.AsuperframealwaysstartsatagivenvalueoftheRCSTlocalNCRcounter,whichservesasareferenceforallburstallocationswithinthesuperframe.ForthepurposeofsynchronizingtothenetworktheRCSTreconstructs,inadditiontothereferenceclock,theabsolutevalueoftheNCCreferenceclock.TheRCSTcomparesthereconstructedvaluewiththeNCRvaluegivenbytheBTP.Thetimereferenceforcountingtimeslotsoccurswhenthevaluesareequal.SIST EN 301 790 V1.2.2:2003

ETSIETSIEN301790V1.2.2(2000-12)16Burstsynchronizationaccuracyshallbewithin50%ofasymbolperiod.Theresolutionshallbe1NCRcountinterval.Theburstsynchronizationaccuracyistheworstcasedeviationofthescheduledstartofbursttimeandtheactualstartofbursttimeatthetransmitteroutput.ThescheduledstartofbursttimeisthepointintimewhentheidealreconstructedNCRequalsthevaluewrittenintheTBTPforthatburst.TheidealreconstructedNCRisdefinedasobservedattheoutputofanidealdelay-lessDVB-Sreceiver.Compensationforthereceiverdelay,ifrequiredtoachievethespecifiedaccuracy,shallbedonebytheRCST.6.1.4SymbolclocksynchronizationThesymbolclockforthetransmittershallbelockedtotheNCRbasedclock,inordertoavoidtimedriftwithrespecttotheNCCreferenceclock.TheRCSTneednotcompensateforsymbolclockDoppler.Symbolclock
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