1
History and TechnologyHistory and Technologyof of IISDBSDB--T T
~ aiming at mobile and ~ aiming at mobile and portable reception ~portable reception ~
17,17, September, 2007September, 2007Argentina Argentina
DiBEGDiBEG, JAPAN, JAPAN
Osamu YamadaOsamu YamadaPioneerPioneer
Digital Broadcasting Expert Group
2
1944 Born in Tokyo
1967 Graduated from Waseda University and joined NHK
1971 Started research of new broadcasting systems
1975-1985 Engaged in the development of Teletext
1985-1992 Engaged in the development of FM multiplex broadcasting
1986-2002 Engaged in the development of terrestrial digital
broadcasting
1991-2000 Engaged in the development of satellite digital broadcasting
1999-2002 Director General of NHK Science and Technical Research Laboratories
2002 left NHK and Joined Pioneer
2005 Senior Managing Director of Pioneer
2007 Executive Corporate Adviser, R&D
BiographyBiography
3
1. History2. TELETEXT3. FM Multiplex Broadcasting4. ISDB-T
4.1 OFDM4.2 Frequency Assignment4.3 Mobile Reception4.4 Effective Usage of Frequency4.5 System Parameter and BST-OFDM4.6 Receivers4.7 New Technologies for Receivers4.8 New Technologies for SFN4.9 International Activities
5. Conclusion
ContentsContents
4
1. Broadcasting History in Japan1. Broadcasting History in Japan
5
History of Broadcasting Technology History of Broadcasting Technology in Japanin Japan
050520002000
95959090858580807575707065656060555550504545404035353030
19251925 25 AM Radio25 AM Radio30 NHK STRL30 NHK STRL
53 TV 53 TV
60 60 NTSC Color TVNTSC Color TV
70 FM Radio70 FM Radio
82 82 TV withTV with MultiMulti--chch AudioAudio84 84 Experimental Analog BSExperimental Analog BS85 85 TELETEXTTELETEXT91 91 Experimental BSExperimental BS HDTVHDTV94 94 FM Multiplex BroadcastingFM Multiplex Broadcasting
00 00 ISDBISDB--SS03 03 ISDBISDB--TT
Radio(28years)Radio(28years)
TV(47years)TV(47years)
Digital(7years)Digital(7years)
Work for NHKWork for NHK(35years)(35years)
6
Research HistoryResearch History
19751975~~19851985 TELETEXTELETEX
19851985~~19941994 FM Multiplex BroadcastingFM Multiplex Broadcasting
19921992~~20002000 ISDBISDB--SS
19861986~~20022002 ISDBISDB--TT
7
2. TELETEXT2. TELETEXT((19751975~~19851985))
8
TELETEXTTELETEXT
(1) TELETEX is the first service with digital technology in analog broadcasting age.
(2) Characters and graphics are coded and multiplexed with the vertical blanking period of analog TV signals.
(3) In 1970s, three systems, System A (France), System B (UK), System C (North America), and System D (Japan) had been developed.
(4) At present, System B, and System D are available.
(5) Japanese each character has a different meaning. Bit errors give erroneous information, therefore bit error can’t be permitted.
(6) Only Japanese TELETEXT system had been making much of the development of error correcting codes.
(7) Japanese TELETEXT never shows incorrect characters, because of the new error correcting method we developed.
9
Field TrialField Trialss of TELETEXTof TELETEXT
FieldField TrialTrial inin WakayaWakayamama
Error PatternError Pattern AnalizerAnalizer
10
Research ResultResearch Result
(1) The simulation results using error patterns collected inthe actual field trials showed that the (272,190) code wasthe best.
(2) The (272,190) code is one of the majority logic decodablecodes, and it is called a difference Set Cyclic Code.
(3) The (272,190) code is one of LDPCs (Low Density ParityCheck), which are hot topics in an error correcting codefield.
11
Packet Signals of TELETEXTPacket Signals of TELETEXT
12
Error Correcting Capability of Error Correcting Capability of the (272,190) Codethe (272,190) Code
0 2 4 6 8 10 12 10 -7
10 -6
10 -5
10 -4
10 -3
10 -2
10 -1
Bit-
erro
r ra
te
Eb/No (dB)
(272,190) Product code
(272,190) code Convolutional code (Viterbi hard 1/2)
No coding
13
Error Correcting Capability of Error Correcting Capability of the (272,190) Codethe (272,190) Code
10-6
10-8
10-10
10-12
10-14
10-16
10-18
10-20
10-22
10-4 10-3 10-2
A B
A : Error correctionB : Error detection
Bit Error Rate of Received Signals
Bit
Err
or R
ate
afte
r E
rror
Cor
rect
ion
or
Det
ecti
on
14
Effect of the (272,190) CodeEffect of the (272,190) Code
Ghost interference(Delay time:2.5μs,D/U=7dB,
Bit-error-rate:4.03x10-3)
Random noise(Input level:31dBμV,Bit-error-rate:2.4x10-2)
15
Applications of the (272,190) CodeApplications of the (272,190) Code
(1) TELETEXT : (272,190)(1) TELETEXT : (272,190)(2) FM multiplex Broadcasting : Product Code(2) FM multiplex Broadcasting : Product Code--
(272,190)X(272,190)(272,190)X(272,190)(3) Optical Card System for immigration card in (3) Optical Card System for immigration card in
U.S.A : Product CodeU.S.A : Product Code--(272,190)X(272,190)(272,190)X(272,190)(4) Protection for key of BS Pay TV : (272,190)(4) Protection for key of BS Pay TV : (272,190)(5) ISDB(5) ISDB--T : Shortened (184,102) for TMCC T : Shortened (184,102) for TMCC
signalssignals
16
What we were taughtWhat we were taught
(1)(1) Digital signals are robust against random noise, but very Digital signals are robust against random noise, but very weak against wave distortion.weak against wave distortion.
(2) Error correction is one of the key technologies in digital (2) Error correction is one of the key technologies in digital broadcasting, and indispensable technology for digital broadcasting, and indispensable technology for digital transmission.transmission.
(3) Thanks to the progress of LSI, theoretically difficult theme(3) Thanks to the progress of LSI, theoretically difficult themes s can be realized.can be realized.
(4) Though analog TV can be received in running cars to some (4) Though analog TV can be received in running cars to some extent, TELETXE signals(5.27Mbps) canextent, TELETXE signals(5.27Mbps) can’’t be received.t be received.
(5) At that time, I believed that digital terrestrial TV (5) At that time, I believed that digital terrestrial TV broadcasting would be impossible, because of high bit rate broadcasting would be impossible, because of high bit rate of video signals and difficulty of mobile reception.of video signals and difficulty of mobile reception.
17
3. FM Multiplex Broadcasting3. FM Multiplex BroadcastingーーDARC(Data Radio Channel)DARC(Data Radio Channel)ーー
(1986(1986~~1995)1995)
18
Frequency Spectrum of Frequency Spectrum of FM Stereo Broadcasting SignalsFM Stereo Broadcasting Signals
0 20 40 60 80 100
-60
-40
-20
0
Baseband frequency (kHz)
Leve
l (dB
)
0 20 40 60 80 100
-60
-40
-20
0
L+R
Pilot
L-R
Multiplexableband
Leve
l (dB
)
Baseband frequency (kHz)
Original baseband spectrum and multiplexable band of FM stereo broadcasting
Baseband spectrum of FM stereo broadcasting under multipath interference
19
Frequency Spectrum of DARCFrequency Spectrum of DARC
0 20 40 60 80 100
-60
-40
-20
0
Baseband frequency (kHz)
Rel
ativ
e le
vel (
dB)
DARC
Pilot tone
L+R L-R
20
Error Correction of DARC
Powerful error correction by (272,190) product code
Parity
Data
Product code
Parity
Parity
21
Car Navigation System with VICSCar Navigation System with VICS(Vehicle Information Communication System)(Vehicle Information Communication System)
Penetration in March, 2006Penetration in March, 2006
1.5 Million1.5 Million
22
Example of VICSExample of VICS
Red Red :: heavy traffic jamheavy traffic jam
Yellow Yellow :: traffic jamtraffic jam
23
Performance of Performance of the (272,190) product codethe (272,190) product code
0 2 4 6 8 10 1210 -7
10 -6
10 -5
10 -4
10 -3
10 -2
10 -1 B
it-er
ror
rate
Eb/No (dB)
(272,190) Product code
(272,190) code Convolutional code (Viterbi hard 1/2)
No coding
24
Comparison of DARC and RDSComparison of DARC and RDS
System DARC RDS
Subcarrier 76 kHz 57 kHz
Multiplex level 4~10% 2~3%
Modulation LMSK BPSK
Bitrate 16 kbit/s 1.2 kbit/s
Error correction (272,190)
product code (26,16) code
25
What we were taughtWhat we were taught
(1)(1) Many kind of digital modulation methodsMany kind of digital modulation methods
(2) Difficulty of mobile reception : poor antenna gain, fading (2) Difficulty of mobile reception : poor antenna gain, fading interference, ghost interferenceinterference, ghost interference
(3) For example, the difference of antenna gain between fixed (3) For example, the difference of antenna gain between fixed reception and mobile reception is more than 15 dB. reception and mobile reception is more than 15 dB.
(4) Existence of potential need, so called traffic information (4) Existence of potential need, so called traffic information serviceservice
26
44. ISDB. ISDB--TT(1986(1986--2002)2002)
27
Merits of Digital BroadcastingMerits of Digital Broadcasting
(1) Robustness against noise(1) Robustness against noise
(2) Easy channel assignment(2) Easy channel assignment
(3) Effective use of bandwidth(3) Effective use of bandwidth
(4) Mobil and portable reception(4) Mobil and portable reception
(5) High video quality(5) High video quality
(6) Affinity to computer and Internet(6) Affinity to computer and Internet
(7) Easy to add new services(7) Easy to add new services
(8) Fit for LSI technology(8) Fit for LSI technology
28
Introduction of Digital BroadcastingIntroduction of Digital Broadcasting
CableCable
SatelliteSatellite12GHz Band12GHz Band
USUS
AudioAudio
TVTV
9494 200020009696 9898 0202 0404 08080606
CSCS
BSBS ▽▽
▽▽
DirecTV, USSB etc.DirecTV, USSB etc.▽▽
▽▽ DTVDTVEnd of Analog BroadcastingEnd of Analog Broadcasting
▽▽ Canal Sat. etc.(France, Italy, Germany, Spain etc.)Canal Sat. etc.(France, Italy, Germany, Spain etc.)
▽▽UK (BBC) etc.UK (BBC) etc.
▽▽Start broadcasting in 3 metropolitan areasStart broadcasting in 3 metropolitan areas
▽▽110 110 degree CSdegree CS
▽▽
▽▽
ISDBISDB--SS
ISDBISDB--TT
YearYear
Test broadcasting in Tokyo, OsakaTest broadcasting in Tokyo, Osaka
Analog Broadcasting will be closed in 2011Analog Broadcasting will be closed in 2011TerrestrialTerrestrial
EuropeEurope
JapanJapan
TerrestrialTerrestrial
SatelliteSatellite
ISDBISDB--TsbTsb
ISDBISDB--CC
▽▽
TerrestrialTerrestrial
SatelliteSatellite
29
Implementation Schedule of ISDB-T in Japan
1994 MPT asked to Council for technical requirement 1998 Issue of Digital Broadcasting Study Group Report
1999 MPT established technical standard
Apr. 2003 Provisional licenses were awarded
1999-2003 Real Scale Experiment Broadcasting
Dec 1.st 2003 Start of ISDB-T (Tokyo, Nagoya, Osaka)
Feb.2003 Start of Analog channel relocation
Apr 1.st 2006 Start of 1-Segment Broadcasting
Oct. 2006 Start of ISDB-T(main city of the whole country)
Jul. 2011 Analog disappears
30
System RequirementsSystem Requirementsand Principal Technologiesand Principal Technologies
(1)(1) Excellent transmission characteristicsExcellent transmission characteristicsOFDMOFDM
(2) HDTV, mobile and portable services(2) HDTV, mobile and portable servicesOFDM, time interleave, hierarchical OFDM, time interleave, hierarchical transmission and one transmission and one segseg
(3) System flexibility(3) System flexibilitySegment structure Segment structure
(4) Effective use of frequency(4) Effective use of frequencySFNSFN
31
Why Mobile and Portable ReceptionWhy Mobile and Portable Reception
(1) All kind of TV programs including data services can be recei(1) All kind of TV programs including data services can be received at home ved at home in the future, via satellite, cable, internet, etc..in the future, via satellite, cable, internet, etc..
(2) People(2) People’’s outside life times are increasing in the presents outside life times are increasing in the present--day life.day life.
(3) Broadcasters have to anytime serve information including vid(3) Broadcasters have to anytime serve information including video, audio, eo, audio, and data.and data.
(4) Especially, the emergency information service is related to (4) Especially, the emergency information service is related to a matter of life a matter of life and death, therefore it is a very important role for broadcasterand death, therefore it is a very important role for broadcasters to s to provide people with emergency information anytime and anywhere.provide people with emergency information anytime and anywhere.
(5) Above media in (1), can(5) Above media in (1), can’’t provide people such services, and VHF and t provide people such services, and VHF and UHF band frequency used by broadcasters, are the best for mobileUHF band frequency used by broadcasters, are the best for mobile and and portable reception. portable reception.
(6) In the age of the convergence of broadcasting and communicat(6) In the age of the convergence of broadcasting and communication, ion, Broadcasters canBroadcasters can’’t survive without mobile and portable services.t survive without mobile and portable services.
32
4.1 OFDM4.1 OFDM((Orthogonal Frequency Division Multiplex)Orthogonal Frequency Division Multiplex)
33
DABDAB(Digital Audio Broadcasting(Digital Audio Broadcasting))
(1)(1) In 1980In 1980’’s, EBU developed Digital Audio Broadcasting s, EBU developed Digital Audio Broadcasting (DAB).(DAB).
(2) DAB adopted two new digital technologies, OFDM (2) DAB adopted two new digital technologies, OFDM (Orthogonal Frequency Division Multiplex, CCETT in (Orthogonal Frequency Division Multiplex, CCETT in France) and digital audio compression technology (IRT in France) and digital audio compression technology (IRT in Germany).Germany).
(3) We started the research of OFDM as a digital modulation (3) We started the research of OFDM as a digital modulation technology for mobile TV.technology for mobile TV.
(4) We knew that Dr. (4) We knew that Dr. Hirosaki Hirosaki (NEC) had already presented (NEC) had already presented the OFDM technology for the first time in the world.the OFDM technology for the first time in the world.
3434
OFDM SignalsOFDM Signals
Carrier 1
Time domain signal of OFDM wave
+
+
+
=
+
Frequency domain signal of OFDM wave
+
+
+
+
=
Carrier 2
Carrier k
GI Active symbol durationOFDM symbol
Transmissionsignal
f1
f2
fk
f1, f2, f3, fK
Magnitude
Frequency
OFDM is
• Multi-carrier modulation– More than 2,000 carriers in a
6MHz TV channel– Long symbol duration
compare to single-carrier transmission system
• Multipath proof modulation– by adding guard interval
• Modulation/demodulation can be processed by IFFT/FFT.IFFT/FFT.
Spectrum
35
OFDM SignalsOFDM Signals
GuardInterval
Effective Symbol Period
The Same Waveform
Ove
rall
Sig
nal
Magnitude
Frequency
3636
Frequency and Time InterleavingFrequency and Time Interleaving
Suitable for multipathinterference.But, ineffective to flat-fading and impulse noise.
Suitable for fading and impulse interference.But, ineffective tomultipath interference.
Suitable for all kinds of interference.
Frequency & Timeinterleaving
(Carrier & Symbol randomization)
ISDB-T
Frequency domain (Carriers)
Tim
e do
mai
n(S
ymbo
ls)
Following interleaving adopts only multi-carrier transmission system
OFDM signal
Frequencyinterleaving
(Carrier randomization)
(DVB-T)
Timeinterleaving
(Symbol randomization)
37
Modulated OFDM signalsModulated OFDM signals(Time and Frequency domains)(Time and Frequency domains)
TimeSymbolsGuard intervals
I F F T F F T
ts tg
Frequency
● ● ● ● ● ● ● ● ● ●
1/ ts
38
Superiority of OFDMSuperiority of OFDM
10
10
10
10
105 8 11 14 17
Eb/NO
BE
R
●
●
●
●
●
●
○ ○ ○ ○ ○ ○
-5
-4
-3
-2
-1
040
30
20
10
0
5 10Delay (μs)
Multipath Profile
(dB)D/U
No Ghost
OFDM
QPSK
39
4.2 Frequency Assignment4.2 Frequency Assignment
40
Application for Marathon Relay StationApplication for Marathon Relay Station25 analog FPU receiving stations ⇒ 7 digital FPU receiving
stations
: Receiving stations: Receiving stations
41
FPU(Field Pick Up) Transmitter and FPU(Field Pick Up) Transmitter and ReceiverReceiver
42
Comparison of FPU between OFDM and Comparison of FPU between OFDM and FMFM
43
Analog TV signals
6MHz
Digital signals
Analog TV signals
Digital signals
Digital signals
Frequency
Total bandwidth : 6MHz
6MHz
Original of BSTOriginal of BST--OFDMOFDM(Band Segmented Transmission(Band Segmented Transmission--OFDMOFDM))
Analog TV signals
[Old name was BST(Band-Split-Transmission)-OFDM]
44
The
num
ber
of tr
ansm
issi
on s
tatio
ns fo
r an
alog
ue T
V
0
100
200
300
400
500
600
700
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62
VHF UHF
Channels
UHF lower channels
basicallyAdjustment of analoguechannelsexcept major stations
Adjustment ofanalogue channels
13 14 15 16 17 18 19 … … … 25 26 27 28 29 30 31 32
ISDB-T channels
…
Channel ReassignmentChannel Reassignment(Analog(Analog--Analog Frequency Conversion)Analog Frequency Conversion)
45
4.3 4.3 Mobile ReceptionMobile Reception
46
Field Trials of Mobile Reception TV Field Trials of Mobile Reception TV for the First Time in the World (1993)for the First Time in the World (1993)
47
Comparison between Digital(OFDM) Comparison between Digital(OFDM) and Analog Broadcastingand Analog Broadcasting
AnalogOFDM
48
Information BitInformation Bit--rate v.s. C/Nrate v.s. C/N
C/N (dB)0 5 10 15 20 25
0
5
10
15
20
25
1/2
DQPSK
2/316 QAM
64 QAM
Guard interval : 1/8
3/45/6
7/8
QPSK
Info
rma
tion
bit
rate
(M
bit/
s)
49
Effect of Time Interleaving (1)Effect of Time Interleaving (1)
0 10 20 30 4010-7
10-6
10-5
10-4
10-3
10-2
10-1
100
BE
R
C/N [dB]
without time interleaving
with time interleaving
fd = 7 Hz fd = 20 Hz fd = 70 Hz
50
Effect of Time Interleaving (2)Effect of Time Interleaving (2)
70
75
80
85
90
95
100
35 40 45 50 55 60 65Measured Field Strength (dBμV/m)
Cor
rect
Rec
epti
on T
ime
Rat
es (
%)
With Time Interleaving
Without Time Interleaving
Mode 2, DQPSK, 1/2 , 13 seg.
99%
Result of field trials
51
4.4 4.4 Effective Usage of FrequencyEffective Usage of Frequency(SFN : Single Frequency Network)(SFN : Single Frequency Network)
Routes of Mobile Reception Routes of Mobile Reception MeasurementsMeasurements
Measured Points
NHK
NHK Labs.
··
··
·
·
··
·
·
Route 20
YamateAvenueSetagaya Avenue
Route 246
Kan
jo 8
Kan
jo 7
8Km
53
Transmitter A : ON, B : OFFTransmitter A : ON, B : OFF
139.62 139.64 139.66 139.68 139.735.62
35.64
35.66
35.68
East Logitude
No
rth
La
titu
de
BER>10-2
BER<10-2
Transmitter B (OFF)
Transmitter A (ON)
54
Transmitter A : OFF, B : ONTransmitter A : OFF, B : ON
139.62 139.64 139.66 139.68 139.735.62
35.64
35.66
35.68
East Logitude
No
rth
La
titu
de
BER >10-2
BER <10-2
Transmitter B (ON)
Transmitter A (OFF)
55
Transmitter A : ON, B : ONTransmitter A : ON, B : ON
139.62 139.64 139.66 139.68 139.735.62
35.64
35.66
35.68
East Logitude
No
rth
La
titu
de
BER>10-2
BER<10-2
Transmitter B (ON))
Transmitter A (ON)
100W
SFN Fie ld Tria ls in S ingaporeSFN Fie ld Tria ls in S ingapore
C h.54
C h.32
C h.32
Bukit BatokBukit Batok
TCSTCS
300M100M
50Wapp.7km
57
SFN field trials in Hong KongSFN field trials in Hong Kong
100W
10W
58
4.5 4.5 System Parameter andSystem Parameter andBSTBST--OFDMOFDM
59
SegmentationSegmentation
Television BroadcastTelevision Broadcast Audio BroadcastAudio Broadcast
Partial ReceivePartial Receive
DataDataSegmentSegment
TransmissionTransmissionSpectrumSpectrum
AudioAudioProgramProgram
HiHi--VisionVisionProgramProgram
OFDF SegmentOFDF Segment
Simple TVSimple TV(Mobile)(Mobile)
Standard TVStandard TV(Mobile)(Mobile)
Standard TVStandard TV(Home)(Home)
AudioAudioProgramProgram
AudioAudioProgramProgram
Data, Data, etcetc
Terrestrial Digital Television SetTerrestrial Digital Television Set Terrestrial Digital Audio ReceiverTerrestrial Digital Audio Receiver
60
Features of ISDBFeatures of ISDB--T systemT system6MHz
13 Segments
Fixed Reception
13 or 1 segment
Mobile/HandheldReception
Handheld terminal
HDTV
Home Receiver
13 segments
Receiver in Vehicle
Communication / Internet
TV stationTV station
Communication carrier
(diversity reception)1 segment
Support 3 reception typesby one channel
61
Transmission ParametersTransmission Parameters
ModeModeMode 1Mode 1(Mobile)(Mobile)
Mode 2Mode 2(Mobile, Fixed)(Mobile, Fixed)
Mode 3 Mode 3 (Fixed)(Fixed)
Number of carrierNumber of carrier
Carrier distanceCarrier distance
Valid symbol lengthValid symbol length
Guard interval lengthGuard interval length
ErrorErrorcorrectioncorrection
inner codinginner coding
outer codingouter coding
Time domain interleaveTime domain interleave
OFDM segment OFDM segment
Bit rate Bit rate
14051405
33.968.968kHzkHz
00.252.252msms
28092809
1.9841.984kHzkHz
00.504.504msms
49924992
0.9920.992kHzkHz
1.0081.008msms
1/4, 1/8, 1/16, 1/32 1/4, 1/8, 1/16, 1/32 of valid symbol lengthof valid symbol length
Convolution coding (1/2, 2/3, 3/4, 5/6, 7/8)Convolution coding (1/2, 2/3, 3/4, 5/6, 7/8)
ReedReed--Solomon (208, 188)Solomon (208, 188)
Convolution 0, 0.1, 0.2, 0.4 secondConvolution 0, 0.1, 0.2, 0.4 second
1313
3.65 3.65 –– 23.23 23.23 MbpsMbps
62
Mode 1(for mobile)
⇒ ⇒
Same signals
Mode 2(for mobile &fixed)
Mode 3(for fixed)
Guard interval
Effective length of symbol
Change of input level in mobile reception
T(time)
Effective length of symbolGuard interval
Difference of ModesDifference of Modes
63
ARIB Standards and ITUARIB Standards and ITU--R R RecommendationsRecommendations for ISDBfor ISDB--TT
-TR-B14ISDB-T broadcasting operationOperational guideline
-STD-B21ISDB-T receiverReceiver
BT.1306System CSTD-B31ISDB-T transmissionTransmission
-STD-B25Multi 2Conditional access
BT.1300, BT.1209
STD-B10, STD-B32MPEG-2 Systems (ISO/IEC 13818-1)Multiplex
BT.1699STD-B24BML (XHTML), ECMA ScriptData broadcasting
BS.1115STD-B32MPEG-2 AAC (ISO/IEC 13818-7)Audio coding
BT.1208STD-B32MPEG-2 Video (ISO/IEC 13818-2)Video coding
ITU-R Recommendations
ARIB StandardsContentsItems
64
TMCC(Transmission and Multiplexing TMCC(Transmission and Multiplexing Configuration Control)Configuration Control)
1-bit16-bit
3-bit
102-bit
82-bit
ECC
204-bit
Reference of difference modulationSync-signal
Coherent/difference, segment ID
TMCC information
Parity
TMCC signals are transmitted on specified carriers every segment to show the transmission parameters, modulation, error correction, partial reception, etc..TMCC signals are modulated with BPSK, and error protected by the (184,102) code.
65
Contents of TMCC InformationContents of TMCC Information
System ID(TV/Audio)Count down counterEmergency
Currentinformation
Flag of partial reception(one seg)Transmission parameter of layer ATransmission parameter of layer BTransmission parameter of layer C
Next information
ContentNumber of bit
2411
1313134015 Reserve
66
Video FormatVideo Format
Vertical Horizontal Aspect ratio Frame frequency
1080(1125) 1440, 1920
480(525) 720
480(525) 720, 480
720(750) 1280
1080(1125) * 1440, 1920
(i) : interlace
(p) : progresive
* : Future system
29.97(i)16:9
16:9
16:9, 4:3
16:9
16:9
59.94(p)
29.97(i)
59.94(p)
59.94(p)
67
Pilot Broadcasting in JapanPilot Broadcasting in Japan
Sapporo
Sen-dai
Nagano
Kanazawa
Nagoya
Osaka
Hiroshima
Fukuoka
Naha Takamatsu
11 Areas in whole Japan11 Areas in whole Japan
Transmission tests supported by the government were held during1999 to 2003.
Open to public fordevelopment ofservices and business.
Tokyo
68
Features of ISDBFeatures of ISDB--TT(1) System flexibility :
Segmentation, Hierarchical transmission
(2) Robustness against impulse noise and multi-path interference :OFDM, Time interleaving
(3) Mobile reception :OFDM, Time interleaving,
(4) Portable reception :OFDM, Time interleaving, One seg(partial reception)
(5) Effective frequency usage :SFN
(6) Compatibility with radio services :Segmentation
Only ISDB-T can provide fixed, mobile and portable services simultaneously. ATSC and DVB-T can’t do.
69
Comparison of Three Comparison of Three DTTBsDTTBs
Item Japan(ISDB-T)
Europe(DVB-T)
US(DTV)
Note
Format BST-OFDM OFDM 8VSB
Ghost ○ ○ △
Japan and Europe employ OFDM, which is robust against ghost.8VSB of US can suppress ghost with ghost canceller.
Effective use ofbandwidth
○ ○ × OFDM can make network with one frequency (SFN).
Mobile receiver ○ △ × DVB-T can mobile reception in a good condition area.
Flexibility ○ △ ×The segmentation technology allows ISDB-T to provide HDTV and audio/SDTV programs simultaneously
70
Data Services Data Services
(1) Program linked data servicesActor’s information, out line of the story, etc.
(2) Program non-linked servicesNews, weatherforecast, stock market information, etc.
(3) Closed captionfor hearing impaired persons
(4) Interactive servicesvia telephone line, via internet
(5) EPG(Electronic Program Guide)TV program guide, booking to record programs, etc.
71
4.6 4.6 ReceiversReceivers
72
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
2003 2004 2005 2006 2007 2008 2009 2010 2011
Estimation of the Number of Digital Estimation of the Number of Digital Broadcasting Receivers in JapanBroadcasting Receivers in Japan
AthensOlympic Games
FIFA World CupGermany
BeijingOlympic Games
Stop ofAnalog Broadcasting
FIFA World Cup
From The Association for Promotion of Digital Broadcasting
Sales Volume
Househols
[[x10000]x10000]
73
TV Shipments (domestic market)TV Shipments (domestic market)From JEITAFrom JEITA
00
100100
200200
300300
400400
500500
600600
700700
800800
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May
CRTCRT
PDP + LCDPDP + LCD
20042004 20052005
Num
ber
of u
nits
[x1
000]
Num
ber
of u
nits
[x1
000]
JEITA : Japan Electronics and Information Technology Industries JEITA : Japan Electronics and Information Technology Industries Association Association
74
Cellular Phones with OneCellular Phones with One--SegSeg
75
Penetration of Cellular Phone Penetration of Cellular Phone with Onewith One SegSeg
x 106
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
Mar-06 Jul-06 Oct-06 Jan-07 Apr-07 Aug-07
From JEITA
76
InIn--car TV Receiverscar TV Receivers
CAV-TD85D1
Mini GORILLA NV-SD10DT
GORILLA NV-HD830DT
Strada CN-HDS965TD
HS706D-A
Panasonic
SANYONISSAN/SANYO
Portable Navigation DeviceFull-Seg/One-Seg
One-Seg Only
SANYO
SANYO
Pioneer
AVIC-VH099G
In-Car TV
Navigation System
※Full-Seg is Optional
One-Seg Only
One-Seg Only
All-in-one model
Tuner separated model
77
PCs with ISDBPCs with ISDB--T tuner (OneT tuner (One--SegSeg))
Tuner
78
USB Type ISDBUSB Type ISDB--T Tuners for OneT Tuners for One--SegSeg
79
Portable DVD PlayerPortable DVD Playerwith ISDBwith ISDB--T tuner (T tuner (OneOne--SegSeg))
80
Other Portable OneOther Portable One--SegSeg ReceiversReceivers
Portable Audio Player
Portable Navigator
Portable Electronic Dictionary
Portable TV
81
Penetration of ISDBPenetration of ISDB--T ReceiversT Receivers
Tuner, CRT, LCD, PDP, STB, DVD Recorder, PCTuner, CRT, LCD, PDP, STB, DVD Recorder, PC
24.1 Million24.1 Million
Mobile Phone with One Mobile Phone with One SegSeg
9.9 Million9.9 Million
Car TVCar TV
0.65 Million 0.65 Million
PC with One PC with One SegSeg
0.12 Million 0.12 Million
Total 34.77 MillionJEITA 2007.6
82
4.7 4.7 New Technologies for ReceiversNew Technologies for Receivers
83
with Error Concealment without Error Concealment
Error Concealment TechnologyError Concealment Technology-- Enable the stable reception of Digital terrestrial HDTV broadcasEnable the stable reception of Digital terrestrial HDTV broadcasting in a ting in a
moving carmoving car
-- When demodulated data include errors, it conceals errors of videWhen demodulated data include errors, it conceals errors of video/audio o/audio and reduce eyesore.and reduce eyesore.
Nov.2005 releasedNov.2005Nov.2005 releasedreleased
84
Image of border area
1seg reception area
12seg reception areaHDTV
H.264
Smooth Handover between Smooth Handover between 12seg and 1seg12seg and 1seg
1seg reception area
12seg reception area
Smooth Handover
-- Both decoding HDTV & H.264 at border area enableBoth decoding HDTV & H.264 at border area enable
-- Quick responseQuick response
-- Free from Free from ““BlackoutBlackout”” picturepicture
H.264
HDTV
Apr.2006 releasedApr.2006Apr.2006 releasedreleased
85
4.8 4.8 New Technologies for SFNNew Technologies for SFN
86
Reception in SFNReception in SFN
NHK
CLI CancellationMain station
NHK
SubscriberRelay stationSea, Lake
Diversity reception
NHK
SubscriberSFN relaystation
NHK
SFN relay station
NHK
SFN stations outside the dedicated area
Desiredsignal
Large delay signal
Large delay multi-path equalization
Reflected signal
Desired signal
CLI
Subscriber
CLI: Coupling Loop Interference
87
Diversity Reception SystemDiversity Reception Systemfor Relay Broadcastingfor Relay Broadcasting
upconverter
downconverter
adaptive filtering algorithmfor diversity combining
downconverter
FIRfilter
FFT
branch #1
FFT
branch #2
receiving antenna
transmitting antenna
adaptive control
adaptive control
signal combiner
extractedscattered pilots
extractedscattered pilots
FIRfilter
88
Example of Two Branch OperationExample of Two Branch Operation
TransmittingAntenna
Input signal spectrum #1
Output signal spectrum
Input signal spectrum #2
Receiving antenna #1
Receiving antenna #2
Signal improvement by diversity reception relay system(Multi-path condition: D/U = 6dB,delay time = 1μ sec)
89
Coupling Loop Interference CancellerCoupling Loop Interference Canceller
Tx UnitRx Unit
TransversalFilter
FilterControl
Coupling Loop Interference Canceller
Coupling Loop Interference(CLI)
FromMaster station
ReceivingAntenna
TransmittingAntenna
Before cancelling After cancelling
90
Improvement in CNRImprovement in CNR
0
1
2
3
4
5
6
-5 0 5 10 15DUR of CLI (dB)
Deg
rada
tion
of R
equi
red
CN
R (
dB)
without canceller
with canceller
91
LongLong--delay Multipath Equalizerdelay Multipath Equalizer
Multi-path delay detection : based on the decision of all OFDM carriers
Long-delay Multipath Equalizer
OFDM Demodulation
+
FilterControl
AdaptiveFilter
-
Desired Wave
Long-delayMultipath
92
Extended Equalization RangeExtended Equalization Range
0 100 200 300 400 500 600 700 800 900 100010
-4
10-3
10-2
10-1
100
Delay of multipath (μs)
BER
With equalizer
Without equalizer
Equalizing range of delay
D/U=6dBC/N=30dB
GITu/8
93
Coupling Loop Interference CancellerCoupling Loop Interference Canceller
Tx UnitRx Unit
TransversalFilter
FilterControl
Coupling Loop Interference Canceller
Coupling Loop Interference
FromMaster station
ReceivingAntenna
TransmittingAntenna
Before cancelling After cancelling
•About 10 companies are developing cancellers.•The development is advanced by a national project of TAO.
(TAO: Telecommunications Advancement Organization of Japan)
94
4.9 4.9 International ActivitiesInternational Activities
International ActivitiesInternational Activities
(1) In 1990s, ISDB-T had been reported in ITU-R, TG11/3, and recommended as a international broadcasting system in ITU-R Assembly meeting held in Istanbul in 2000.
(2) Asian-Pacific Broadcasting Union (ABU) had held Workshop on DTTV since 1998, and DiBEG had been participating in it.
(3) Since 1990s, the ISDB-T group participated in many international meetings on DTTV to explain the superiority of ISDB-T to the world, ITU-R, ABU, IBC, NAB, BroadcastingAsia, SMPTE, SET(Brazil), ISBT(China), etc..
(4) In 1998, DiBEG participated in Singapore and Hong Kong carried out the comparison tests of three systems.
(5) In 2000, Brazil carried out the same comparison tests, and they unveiled tests results for the first time in the world. The results showed ISDB-T was the best.
(6) DiBEG has been proceeding with the penetration activities of ISDB-T in the world, focusing on South America and Asia.
96
Trial Area(Singapore)Trial Area(Singapore)(Sight from Temple Hill Station)(Sight from Temple Hill Station)
Experimental routes
97
Results of Mobile Reception Results of Mobile Reception In SingaporeIn Singapore
ISDB-T, 2secDVB-T
DVB-T
DVB-T
Comparison tests between DVB-T and ISDB-T
DVB-T: many impossible places
98
Systems Systems PrametersPrameters for Tests(in Brazil)for Tests(in Brazil)
ATSC DVB-2K DVB-8K ISDB-T
Modulation 8VSB COFDM COFDM COFDM
Payload 19,39 Mbits/s 19,75 Mbits/s 18,09 Mbits/s 19,33 Mbits/s
Receivers Zenith NDS NDS NECChip TChip UChip SChip A
New receivers
Chip N Chip JChip L
Chip M
99
Impulse NoiseImpulse Noise
Better performance of the ISDB-T system, by introducing time interleaving
Relation between the noise pulse width & interference to signal ratio
-15
-10
-5
0
5
10
15
20
25
30
0 100 200 300 400
Pulse width (us)
"I"/
C (
dB)
ATSC - Chip A
DVB - NDS - 3/4 1/16 2K
DVB - Chip M - 2/3 1/32 8K
ISDB - NEC - 3/4 1/16 4K 0,1s
100
Outdoor: CoverageOutdoor: Coverage
Success on Receiving - Cumulative FunctionCriterion: Number of Errors < 5
60%
70%
80%
90%
100%
0 5 10 15 20 25 30 35 40
Distance (km)
Per
cen
tag
e o
f S
ites
ATSC DVB-2k DVB-8k ISDB-T
101
Tests Results of Mobile ReceptionTests Results of Mobile Receptionin Brazilin Brazil
Experiment of field mobile in BrazilExperiment of field mobile in Brazil
ParameterParameterStandardStandard
ModulationModulation GuardGuardLengthLength CarrierCarrier
TransmissionTransmissionRate Rate
(Mbps)(Mbps)
ErrorsErrors(Times)(Times)
1616QAMQAM 2/32/3 1/161/16 22kk 11.4511.45 00
6464QAMQAM 2/32/3 1/161/16 22kk 17.1817.18 66ISDBISDB--TT
1616QAMQAM 2/32/3 1/161/16 44kk 11.4511.45 00
QPSKQPSK 1/21/2 1/161/16 22kk 4.394.39 11
QPSKQPSK 2/32/3 1/161/16 22kk 5.855.85 ManyManyDVBDVB--TT
QPSKQPSK 1/21/2 1/321/32 88kk 4.524.52 ManyMany
ATSCATSC 88VSBVSB 19.3919.39 Out ofOut ofmeasurementmeasurement
ConvolutionConvolution
For For ATSCATSC’’ss InsistenceInsistenceATSC : The ATSC’s service area is larger than DVB-T and ISDB-T.
“This is the natural result. In addition to pure information, both DVB-T and ISDB-T are transmitting guard interval signals against multi-path interferences. The guard interval signals are redundant, but to transmit such a countermeasure signals is indispensable against multi-path interferences, which always take palace and are inevitable in the terrestrial transmission paths.”
“ATSC doesn’t have such a function as the guard interval, and transmission power is used only for the information transmission. Therefore, theATSC’s service area is large, but the actual receiving performance arevery poor, as people always experience. ATSC don’t use the transmission power for the countermeasure signals against indispensable multi-path interferences in the terrestrial transmission.”
“ATSC is just like without error correcting codes in digital systems. ATSCis the naked system against multi-path interferences”
“The ATSC side always says “that the next generation multi-path equalizer has been under development”. At present, I heard the next generation was the fifth. They maybe have to continue to develop the next generation equalizer for ever.”
For DVBFor DVB--TT’’s Insistences InsistenceDVB-T :
(1) The one seg function can’t be adopted for the GSM cellular phones.(2) Concerning mobile reception, DVB-H can cover these services.(3) ISDB-T’s receivers are very expensive.
“ All above comments are incorrect. ”
“ In Japan, GSM is not used, therefore currently there are not the GSM cellular phones with one seg in the market. Therefore, it is not a technical matter and not a crucial matter, but a false charge against us. Docomo and other manufactures are supposed to put their cellular phones with roaming function and one seg this year. ”
“ DVB-H is a different system from the original DVB-T. Since DVB-T doesn’t have a hierarchical transmission function, DVB-T can’t broadcast HDTV with high bit rate and mobile services simultaneously. ”
“ As I mentioned in my presentation, many kinds of ISDB-T receivers from many manufactures are on the market. The price is going down year by year. As there are not DVB-T receivers for 6MHz and for HDTV reception in the market, we can’t make comments on the price of DVB-T receivers. ”
104
5. 5. ConclusionConclusion
105
(1) Digital broadcasting has been penetrating in the world and l(1) Digital broadcasting has been penetrating in the world and leading eading digital consumer electronics.digital consumer electronics.
(2) The number of digital broadcasting receivers has been increa(2) The number of digital broadcasting receivers has been increasing sing rapidly in the world.rapidly in the world.
(3) (3) The Japanese The Japanese terrestrial digital broadcastingterrestrial digital broadcasting (ISDB(ISDB--T)T) had been had been developed based on the experiences of the development of TELETEXdeveloped based on the experiences of the development of TELETEXT T and FM multiplex broadcasting systems.and FM multiplex broadcasting systems.
(4) In Japan, ISDB(4) In Japan, ISDB--T T receivers have been penetrating fastest in the world.receivers have been penetrating fastest in the world.
(5)(5) ISDBISDB--TT has a lot of merits, system flexibility, mobile and portable has a lot of merits, system flexibility, mobile and portable reception, SFN, robustness against any interferences etc.reception, SFN, robustness against any interferences etc.
(6)(6) BrazilBrazil decided decided to adopt to adopt ISDBISDB--T T as their national systemas their national system last year,last year, on on the results of comparison of three systems.the results of comparison of three systems.
(7) Only ISDB(7) Only ISDB--T can satisfy the need of all people, and contribute to the T can satisfy the need of all people, and contribute to the improvement of the life of all people.improvement of the life of all people.
ISDBISDB--T is the best.T is the best.
ConclusionConclusion
106
Since radio frequencies are the common resources for people, we have to use them usefully.
The most effective usage for VHF and UHF is for mobile and portable applications.
Once we decide the DTTB system as a national broadcasting standard, we can’t change the system anymore.
We should select the best system for descendants not to regret it later.
If you make a correct selection, we, Japanese side will do our best for Argentina.
Let’s work together !
Once AgainOnce Again
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