Global Standards Collaboration (GSC) 14
DOCUMENT #:
GSC14-GRSC7-021R1
FOR:
Presentation
SOURCE:
TTA, Korea
AGENDA ITEM:
4.2
CONTACT(S):
Daejung Kim (kdj@tta.or.kr)
Advanced T-DMB (AT-DMB) standard
for Enhanced Mobile TV Service
DJey KIM(kdj@tta.or.kr)
TTA
Geneva, 13-16 July 2009
Fostering worldwide interoperability
Highlight of Current Activities
Standardization Status of TTA PG801
Work scope of TTA PG801(DMB Project Group)
Development of DMB Standards
Promoting international harmonization of DMB
TTA T-DMB Standards
T-DMB Basic interface standards (’05)
T-DMB data broadcasting Standards (’08)
International Harmonization
T-DMB was reflected in ETSI, ITU-R REC-BT.1883 (‘07)
T-DMB Middleware platform Spec.(TTAS.KO-07.0049)
will be harmonized with ETSI Spec in 2009
Fostering worldwide interoperability
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Highlight of Current Activities
T-DMB Service in Korea
Service coverage
After launched in 2005, T-DMB service covers the
whole national area including Seoul subway area now
T-DMB receivers
The Number of DMB receivers reached 15 mil. (‘08)
- Every family owns at least one T-DMB receiver
DMB Market
T-DMB DMB receiver market is strongly driven by two
types of convergence devices such as mobile phones
and car navigation systems
* Mobile operators(KT) have begun to aggressively push interactive services based
on BIFS technology to create additional revenue using T-DMB.
* Most navigation systems now support DMB In addition TPEG services are becoming
another attractive feature of DMB enabled navigation systems(Real-time traffic
information via TPEG)
Fostering worldwide interoperability
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Highlight of Current Activities
T-DMB Service in Korea
Network Cost
The network investment of T-DMB is less than that the
other Mobile TV service with similar coverage
Channel capacity
But, T-DMB could provide less number of services than
the other Mobile TV.
More channel capacity for variety multimedia
and data services was required within the
limited frequency band.
Fostering worldwide interoperability
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Strategic Direction
Requirements for new enhanced standard(AT-DMB)
Backward compatibility with the T-DMB service
Increasing data rate up to maximum twice vs. T-DMB
More service models of AT-DMB
Available as DTV alternative service in developing
countries
Interactive data services using extended channels of ATDMB and wireless communications
Fostering worldwide interoperability
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Challenges
For Backward compatibility
Composed of base layer and enhancement layer
** BL(T-DMB service), EL(additional data and video service)
For increasing payload in Enhancement layer
Hierarchical Modulation
** Technique for multiplexing and modulating multiple data streams into one single
symbol stream (This was also adopted to TIA Mediaflo and ETSI DVT-T Spec)
Turbo code
** This has better performance compared with convolutional code applied to T-DMB

By increased payload, It is possible to commercialize MultiChannel Service in mobile environment & High-Quality Service
in fixed environment
Fostering worldwide interoperability
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Future Direction
As TTA Standard
•
•
TTA published AT-DMB std. in June 18, 2009
For enhancement of service
Develop Specs for interactive data services
using extended channels of AT-DMB (Return channel:
wireless communications)
For International Harmonization
Presented at WorldDMB Meeting
contribute to ITU-R SG6 at the end of 2009
Fostering worldwide interoperability
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Supplementary Slides
Geneva, 13-16 July 2009
Fostering worldwide interoperability
8
Concept of Multi-channel Service
(AT-DMB)
Fostering worldwide interoperability
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Concept of high quality Service
Fostering worldwide interoperability
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AT-DMB Standard Overview
AT-DMB Standard
Hierarchical modulation mode
categories
B-mode
Q-mode
Bandwidth
Effective
data rate
Transmission
1.536 MHz
BL
EL
0.8~1.728 Mbps
0.288~0.576 Mbps
0.576~1.152 Mbps
FEC
BL : Convolutional Code, EL : Turbo code
Code rate (EL)
1/2, 2/5, 1/3, 1/4
Modulation
DQPSK(BL), BPSK(EL) or QPSK(EL)
Hierarchal modulation
Video Compression
Audio Compression
Video Resolution
Geneva, 13-16 July 2009
H.264,
SVC (optional)
BSAC,
AAC+ (optional),
MPEG Surround
(optional)
QVGA (320*240),
VGA(640*480, optional)
H.264
SVC
BSAC,
AAC+ (optional),
MPEG Surround
QVGA (320*240),
VGA(640*480)
Fostering worldwide interoperability
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AT-DMB System Overview
System Structure
Base layer frame generation part
FIB mux.
Fast information data
Mux control data & SI
...
Video service
DAB frame mux.
Audio service
Main service mux.
Service infor.(SI)
T-DMB
receiver
Data service
Hierarchical
modulation
Enhancement layer frame generation part
Mux control data & SI
AT-DMB
receiver
DAB frame mux.
Audio service
...
Main service mux.
Service infor.(SI)
Video service
Terrestrial
link
FIB mux.
Fast information data
OFDM
modulation
: Existing T-DMB part
: Additional part for AT-DMB
Data service
Fostering worldwide interoperability
AT-DMB Service model(1)
AT-DMB Service Model – DTV alternative service in developing
countries
 High-Quality Broadcasting Service
 Mobile Environment : Video Service with the QVGA (CIF) size
 Fixed Environment : Video service with the VGA size (Scalable Video Coding)
High-Quality
QVGA  VGA
Mobile Environment
(BL)
Geneva, 13-16 July 2009
Fixed Environment
(BL+EL)
Fostering worldwide interoperability
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AT-DMB Service model(2)
AT-DMB Service Model – Data Broadcasting Service
•
TPEG, BWS, Clipcasting, Filecasting services in the mobile environment
Geneva, 13-16 July 2009
Fostering worldwide interoperability
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Benefit of AT-DMB(1)
Multi-Channel AT-DMB
Basic Channel [BL)
Video 1
Additive Channel (EL)
Video 2
Select
Video
1 Audio 1
Geneva, 13-16 July 2009
Video 3
Fostering worldwide interoperability
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Benefits of AT-DMB(2)
High Quaility Mode
Basic Channel [BL)
Video 1
High-Quality Channel
(EL)
Video 1
Video 1
Select
Video 2
Geneva, 13-16 July 2009
Fostering worldwide interoperability
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Benefits of AT-DMB(3)
Local Broadcasting Service
BL: Existing T-DMB service for resolving the shadowing area
EL: Location based service
- Local advertisement, Local bulletin service, Disaster Broadcasting etc.
T-DMB
AT-DMB
AT-DMB
Fostering worldwide interoperability
Comparison of Mobile-TV Spec
T-DMB
AT-DMB
MediaFLO
DVB-H
Bandwidth
1.536MHz
1.536MHz
5/6/7/8MHz
5/6/7/8MHz
Frequency
VHF/L
VHF/L
VHF/UHF/L
VHF/UHF/L
Modulation
Pi/4 DQPSK
Pi/4 DQPSK(BL)
QPSK, BPSK(EL)
Hierarchical modulation
QPSK
QPSK
16QAM
16QAM
Hierarchical modulation 64QAM
FEC
RS
convolutional
RS
Convolutional(BL)
Turbo(EL)
RS
Turbo
RS(MPE-FEC), RS
Convolutional
Code rate
EEP,UEP
EEP,UEP(BL)
1/2,2/5,1/3,1/4(EL)
1/3, 1/2, 2/3
1/2, 2/3, 3/4, 5/6, 7/8
FFT size
2k,1k,0.5k,0.25k
2k,1k,0.5k,0.25k
1k, 2k, 4k, 8k
2k, 4k, 8k
Interleaving
depth
384msec
384msec(BL)
384msec(EL, Q mode)
768msec(EL, B mode)
750msec
~500msec
73.8km
(GI=246us)
55.4km (4k, GI=1/4)
44.8km(4k, GI=1/4)
2.1~8.4Mbps(@6MHz)
2.8~7.5Mbps(@6MHz,
MPE-FEC=3/4)
Maximum SFN 73.8km
(GI=246us)
size
Payload
0.8~1.728Mbps(@1.5 1.088~2.304Mbps(B mode)
MHz)
1.376~2.88Mbps(Q mode)
Geneva, 13-16 July 2009
Fostering worldwide interoperability
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T-DMB Market Share in Korea
Geneva, 13-16 July 2009
Fostering worldwide interoperability
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Modes for Hierarchical Modulation
Operation Mode
Q
1
 B-Mode
1
0
0
 BPSK for enhancement layer
I
 Payload : max. 50% increase
 Suitable for mobile reception
0
0
1
1
Q
 Q-Mode
 QPSK for enhancement layer
11
10
01
11
01
00
00
10
 Payload : max. 100% increase
 Suitable for stationary reception
I
10
00
00
01
11
01
10
11
Fostering worldwide interoperability
T-DMB Frequency Allotment (1)
T-DMB Freq. Band in Korea
Band
VHF
UHF
Allotment
TV
(ch. 2∼4)
TV
(ch. 5∼6)
FM Radio
TV / T-DMB
(ch. 7∼13)
TV
(ch. 14∼60)
Frequency
(MHz)
54∼72
76∼88
88∼108
174∼216
470∼752
The Metropolitan area
Local Province
Allots 12MHz (ch.8 & ch.12)
6 broadcasters
Allots 6MHz per region (6 regions in Korea)
3 broadcasters per region
Fostering worldwide interoperability
T-DMB Frequency Allotment (2)
Example: ch. 12 (204 ~ 210MHz)
512kHz
Block A
1.536MHz
192kHz
Block B
1.536MHz
MBC
Block C
192kHz
496kHz
1.536MHz
KBS
SBS
TV 1 Channel (6MHz)
204MHz
210MHz
Effective Data Rate 1.152Mbps
video
audio 1
audio 2
audio 3
data
(512kbps)
(128kbps)
(128kbps)
(128kbps)
(256kbps)
Fostering worldwide interoperability
Interactive services
AT-DMB
Network
BL Service
Channels
Video
Mux/COFDM
(BL)
T-DMB interactive services
RF
Channel
Audio
Content
Server
CA
S
Mux/COFDM
(EL)
EL Service
Channels
Hierarchical
Modulation
AT-DMB interactive services
Interactive
Data
Wireless communication network
(WiBro, WCDMA, etc.)
Fostering worldwide interoperability
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