Seamus O'Leary - Understanding Digital Terrestr..

293 Pages·2003·1.28 MB·English

Understanding Digital Terrestrial
Broadcasting
Understanding Digital Terrestrial
Broadcasting
Seamus O(cid:146)Leary
Artech House
Boston (cid:149) London
www.artechhouse.com
LibraryofCongressCataloging-in-PublicationData
O(cid:146)Leary,Seamus.
Understandingdigitalterrestrialbroadcasting/SeamusO(cid:146)Leary.
p. cm.(cid:151)(ArtechHousedigitalaudioandvideolibrary)
Includesbibliographicalreferencesandindex.
ISBN1-58053-063-X(alk.paper)
1.Digitalcommunications. 2.Televisionbroadcasting. 3.Digitalaudio
broadcasting.
I.Title. II.Series.
TK5103.7.O49 2000
621.384(cid:151)dc21 00-040624
CIP
BritishLibraryCataloguinginPublicationData
O(cid:146)Leary,Seamus
Understandingdigitalterrestrialbroadcasting.(cid:151)(ArtechHousedigitalaudioandvideo
library)
1.Digitaltelevision 2.Digitalaudiobroadcasting
I.Title
621.3(cid:146)88
ISBN
1-58053-462-7
CoverandtextdesignbyDarrellJudd
'2000ARTECHHOUSE,INC.
685CantonStreet
Norwood,MA02062
Allrightsreserved.PrintedandboundintheUnitedStatesofAmerica.Nopartofthis
bookmaybereproducedorutilizedinanyformorbyanymeans,electronicormechani-
cal,includingphotocopying,recording,orbyanyinformationstorageandretrievalsystem,
withoutpermissioninwritingfromthepublisher.
Alltermsmentionedinthisbookthatareknowntobetrademarksorservicemarks
havebeenappropriatelycapitalized.ArtechHousecannotattesttotheaccuracyofthis
information.Useofaterminthisbookshouldnotberegardedasaffectingthevalidityof
anytrademarkorservicemark.
InternationalStandardBookNumber:1-58053-063-X
LibraryofCongressCatalogCardNumber:00-040624
10987654321
ThisbookisdedicatedtothememoryofUnaandDenisMcLoughlin,
Goraibhleabaimeascnanaoimhagaibhigc(cid:243)na(cid:237).
(MayyoualwayshaveabedamongsttheSaints.)
Contents
1 CurrentSituation 1
1.1 Introduction 1
1.2 HistoricalBackgroundandFutureTrendsinDigitalTelevision 2
1.3 GlobalDevelopmentsinDigitalTelevision 3
1.3.1 DTVintheUnitedStates 3
1.3.2 DTVinEurope 4
1.3.3 DTVinJapan 4
1.4 DigitalTelevisionOrganizations 5
1.5 TheNeedforCompression 11
1.5.1 RedundancyandEntropy 11
1.5.2 ConstantandVariableRateSources 13
1.6 IntracodingandIntercodingTechniques 14
1.6.1 Intracoding 14
1.6.2 Intercoding 14
2 DigitalEncodingofTelevisionSignals 17
2.2 SamplingFormats 19
2.2.1 Rec.601(ITU-RBT.601-5) 20
2.2.2 QuantizationLevelsin8-BitSampling 21
2.2.3 RedundancyandCompression 21
2.2.4 CompressionEfficiency 22
2.3 ITU-RRec.656Interface 23
2.3.1 SerialDigitalComponentVideo(4:2:2) 23
2.4 4:2:0SampledSignals 25
2.5 ITU-Rec.723 26
vii
viii UnderstandingDigitalTerrestrialBroadcasting
2.6 EncodingSignalsforDTVBroadcasting 27
2.7 DigitalAudioCoding 27
2.7.1 SamplingandQuantizationofAudioSignals 28
2.7.2 AES/EBUDigitalAudioInterface 29
2.7.3 CommonSamplingFrequencies 29
3 SomeCommonDigitalTelevisionStandards 31
3.1 Introduction 31
3.2 MovingPicturesExpertGroup(MPEG) 32
3.3 JointPhotographicExpertGroup(JPEG) 32
3.3.1 JPEGCompression(cid:151)AnOverview 33
3.3.2 LossyandLosslessCompression 33
3.4 MPEG-1 34
3.4.1 MPEG-1Compression(cid:151)AnOverview 35
3.5 Frame-basedandObject-basedCodingStandards 36
3.6 MPEG-4:Anobjectbasedcodingapproach 37
3.7 MPEG-7:AMultimediaContentDescriptionInterface 38
3.7.1 Metadata 38
4 MPEG-2:TheBroadcastersChoice 41
4.1 Introduction 41
4.2 4:2:0Sampling 42
4.3 DiscreteCosineTransform(DCT) 43
4.4 CoefficientQuantization 44
4.5 Zig-ZagCoefficientScanning 45
4.6 VariableLengthCodingandRunLengthCoding 46
4.7 Buffers 47
4.8 InterframeRedundancyCompressionTechniques 47
4.9 Motion-CompensatedInterframePrediction 48
4.10 MPEG-2PictureTypes 49
4.10.1 I-pictures 49
4.10.2 P-pictures 49
4.10.3 B-pictures 49
4.11 GroupofPictures(GOP) 50
4.12 MPEG-2ProfilesandLevels 50
4.13 MPEGAudioCoding 51
4.13.1 MPEG-1Audio 52
4.13.2 MPEG-2Audio 53
4.13.3 DifferentISOMPEGlayers 53
Contents ix
4.13.4 PrinciplesBehindMPEGLayerIICoding 55
4.13.5 Sub-BandCoding 56
4.13.6 MPEGAudioDecoding 57
4.13.7 DVBGuidelinesforAudioCoding 57
5 MPEG-2TransportStreams 59
5.1 Introduction 59
5.2 TheMPEG-2SystemLayer 60
5.2.1 ClockReferenceInformation 60
5.2.2 TransmissionandProgramInformation 60
5.3 MPEG-2BitStreams 61
5.4 MPEG-2Interfaces 63
5.4.1 SynchronousParallelInterface(SPI) 63
5.4.2 AsynchronousSerialInterface(ASI) 65
5.5 MPEG-2TransportStreamParameters 66
5.5.1 ProgramSpecificInformation(PSI) 68
5.5.2 DVBServiceInformation(SI) 69
5.5.3 ServiceInformationDistribution 71
5.6 ConstantandVariableBitRateSources 72
5.6.1 DTVMulticasting 72
5.6.2 StatisticalMultiplexing 73
5.6.3 OpportunisticData 76
6 SingleCarrierDigitalModulations 79
6.1 Introduction 79
6.1.1 UsesofSingleCarrierDigitalModulations 80
6.2 BandlimitingDigitalSignals 80
6.2.1 DigitalSignalsinTimeandFrequencyDomains 81
6.2.2 NyquistFiltering 81
6.2.3 RaisedCosineFilters 83
6.3 DataTransmissionSpeeds 83
6.4 MultilevelDigitalModulations 84
6.4.1 QPSK(QuartenaryPhaseShiftKeying) 85
6.4.2 DataCapacityof2m-QAMSystems 86
6.4.3 BytetoM-TupleConversion 87
6.4.4 16-QAM 88
6.4.5 32-QAMModulation 89
6.4.6 64-QAMModulation 90
x UnderstandingDigitalTerrestrialBroadcasting
6.4.7 QAMModulatorImplementation 91
6.4.8 FilteringofQAMSystems 92
6.4.9 TrellisCodeModulation 92
6.5 DVB-basedQAMSystems 93
6.5.1 DVB-CSystemConcepts 93
6.5.2 CommonOperatingCharacteristicsofDVB-CSystems 94
6.6 VestigialSidebandModulation 95
6.6.1 SystemOverview 95
6.6.2 VSBModulator 96
6.7 SingleCarrierandMulticarrierModulationforTerrestrial
6.7 Broadcasting 97
7 CodedOrthogonalFrequencyDivision
Multiplexing 101
7.1 Introduction 101
7.2 COFDM:AQualitativeDescription 103
7.2.1 FrequencyDivisionMultiplexing 103
7.2.2 Coded 103
7.2.3 Orthogonality 104
7.3 SymbolPeriod,Intervals,andCarrierSpacing 105
7.3.1 ConsequenceofVaryingGuardInterval 107
7.4 TimeDomainSignalandTransmissionConsequences 107
7.5 The2kand8kSystems 109
7.5.1 DataPayloadof2kand8kSystems 110
7.6 InnerCoding(ConvolutionalCodes) 113
7.7 InnerModulation 114
7.8 OuterCoding 114
7.9 PilotCells 115
7.10 RadioFrequencySpectrumCharacteristics 116
7.10.1 RFChannelBandwidth 116
7.11 HierarchicalTransmission 117
7.11.1 PossibleUsesofHierarchicalTransmission 121
7.12 PracticalDVB-TModulators 122
7.12.1 UseofFFTinCOFDM 123
8 TerrestrialTransmissionofDTVSignals 125
8.1 Introduction 125
8.1.1 DigitalandAnalogTransmittedPictureQuality 126
8.1.2 AnalogTransmissionImpairments 126
Contents xi
8.1.3 DigitalTransmissionAdvantages 127
8.2 TransmissionSpectrumIssues 127
8.2.1 AnalogSpectrumAllocationsandFrequencyBands 128
8.2.2 TelevisionPlanning 128
8.2.3 UHFPropagation 129
8.2.4 ConstraintsonAssigningAnalogChannels 130
8.2.5 DTVChannelPossibilities 132
8.3 DigitalTelevisionTransmitters 133
8.3.1 TypicalTransmitterOutputPowers 133
8.3.2 SolidStateTransmitters 134
8.4 DTVTransmitterArchitecture 139
8.4.1 Modulator 139
8.4.2 LinearityPrecorrector 139
8.4.3 RFUpconvertor 139
8.4.4 PowerAmplifierandDerratedOperation 140
8.4.5 DTVTransmitterDistortionsandClipping 141
8.5 Filters,Combiners,andAntennaSystems 141
8.5.1 DTVFilters 142
8.5.2 DTVCombiners 142
8.5.3 DTVAntennaSystems 142
8.5.4 VoltageandPowerRatings 143
8.6 DTVTransmitterSizeandCoolingArrangements 144
8.6.1 AirCoolingSystems(cid:151)DisadvantagesforDTV 144
8.6.2 LiquidCoolingSystems 145
8.6.3 GeothermalCoolingSystems 145
9 DTVReceivers,Measurements,andMiddleware 147
9.1 Introduction 147
9.2 Measurements 149
9.2.1 RFandIFSignalPower 149
9.2.2 NoisePower 149
9.2.3 Carrier-to-NoiseRatio(C/N) 150
9.2.4 BERVersusC/N 150
9.2.5 TransmitterOutputBack-off 151
9.2.6 PhaseNoise 151
9.2.7 TransmitterLinearity 151
9.2.8 EquivalentNoiseDegradation(END) 152