Slide 1 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
DVB-SH … among others
AgendaTerminology
Background on DVB-SH
Highlights of Technical features
Conclusions
Nghia PHAM, [email protected]
Slide 2 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
TERMINOLOGY
What is Mobile TV ?� A system of TV and infos delivery that adapts itself to your receive
environment and timing constraints;
� A system that let you select content, choose format, pause, forward, “start from the beginning”, fast forward, in the best way depending on where you are.
What is a standard ?
� A set of specifications produced by a representative committee with a clear rule for timely initiating the process and concluding it in a consensus-building manner.
What is an open standard ?
� A standard that is royalty-free (or practically so!)
� A standard that is not controlled by a dominant player and is maintained by a representative committee in a participative way.
DVB Satellite to Handheld DVB Satellite to Handheld
Special thanks to the following companies:
Slide 4 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
DVB-SH is about…
� Delivering IP-based media content to handheld and vehicular terminals at frequencies below 3 GHz
� (Unlike any other terrestrial-based solutions)
� providing nationwide coverage
� using harmonised frequencies assigned to Satellite for complementary coverage by terrestrial gapfillers
� Leveraging DVB-H “ecosystem” for joint deploymentMADE IN D
VB
MADE IN D
VB
MADE IN D
VB
MADE IN D
VB
Slide 5 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
BACKGROUND
� Hybrid broadcast already in use : SDARS (US), S-DMB (South Korea & Japan). Together these proprietary satellite systems served >13 Mi users (2006).
� 100…150+ Mi is the estimated number of MobileTV users in the 2010 horizon (e.g. Northern Sky Research, “Enabling Rich Video On the Go”, Feb. 2006)
� June 2006: TM-SSP (Satellite Systems for Portable devices) created, at the initiative of Alcatel with backing from Eutelsat, SES-Astra and others.
� Oct 2006 : Eutelsat & SES-Astra announced the creation of SOLARIS.� S-band GEO satellite scheduled for Q1/09 launch.
� Feb. 2007: DVB-SH normative texts delivered to ETSI. EC directive designates S-band for satellite priority use.
� Jul. 2007 : ALU tests DVB-SH with SFR (french 3G operator).
� IBC Amsterdam 2007 : DVB-SH products advertised by Dibcom, UDcast, Teamcast, Uniquesys, Enensys, SIDSA, Samsung, Sagem, Archos.
� March 2008 : “DVB-SH Implementation Guidelines V1” delivered to ETSI
� April 2008 : ICO G-1 satellite launched, partner with Delphi for terminals, ALU fornetwork (US market). ETSI approved DVB-SH standards
Slide 6 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
‘system’ specificationsTS 102585
WaveformDefinition
EN 302583
ImplementationGuidelines
prTS 102584
DVB-SIEN 300468SH Descriptors
Link layer:EN 301192
MPE-iFEC
SH specifications Collateral specification effort
Synchronization
MIP: ETSI EN101191
updates
references
Synchronization
MIP: ETSI EN101191
ModifiesAndIncludes
SH Specifications within DVB framework
CBMS
Mobility IGIPDC for SH
Slide 7 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
ARCHITECTURE
� Satellite Component (SC) covers mainly rural areas
� Complementary Ground Component (CGC) covers mainly urban areas, including indoor.
� Seamless transitions between - and constructive addition of - signals in overlapping areas, e.g. suburban areas.
� CGC must replicate SC content (“Common Content”). Local content can be offered in addition.
DVB-SH SatelliteDVB-SH Signal
Content
Head-endSatelliteEarthStation
BroadcastDistributionNetwork
PersonalGap-fillers
TerrestrialTransmitters
MobileTransmitters
Distribution signal
Slide 8 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
Complementary Ground Component
Complementary Ground Component (CGC) consists of terrestrial repeaters (TR). Three types can be distinguished:
TR(a): Leverage existing networks infrastructures (e.g. 3G BS, broadcast towers), especially in urban areas . Local content insertion is possible, relying on frequency planning, hierarchical modulation and/or modulation/coding optimisations.
TR(b): Personal gap-fillers of limited coverage providing mainly on-frequency re-transmission; typical application is helper for indoor usage under satellite-only coverage; no local content insertion.
TR(c): Mobile transmitters creating a “moving complementary infrastructure”. Depending on waveform configuration and radio frequency planning, local content insertion may be possible.
Slide 9 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
A challenging obligation: maximise spectral efficie ncy
� Available bandwidth is limited (as always).
� How many Mbits can be offered in the satellite coverage and how many Mbits can be offered in the terrestrial coverage?
� To be competitive, a minimum of 20-30 programs (at QVGA resolution) must be offered per country in urban areas and a minimum of 7-10 programs over 100% of territory.
� In Europe, linguistic zones exist. A multi-beam satellite system allows frequency reuse between satellite beams as well as between satellite beams and terrestrial repeaters.
Slide 10 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
A challenging task: several terminal types & use cases
G/T ~ -21 dB/K
Vehicular
Doppler = 230 Hz
(130Km/h)
G/T ~ [-25,-29] dB/K G/T ~ -32 dB/K
Embedded
antenna
Enhanced
antenna
Handheld
Small antenna(s). Small form factor
Battery conservation
User cooperation may be required
for satellite direct reception
Personal gap-filler
G/T ~ -19dB/K
High gain antenna
Used mostly indoor
No time diversity
Dual antenna (circular &
vertical polarisation)
Harsh environments in satellite-
only reception
Large display
Slide 11 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
A challenging environment: direct satellite recepti on
S a te llited irec t p a th s
IM R
e .g . K u /K a -b a nd sa te lliteIM R fe eds ig na l
S a te llitee c ho p a th s
IM R e c hop a th /s c a tte r
P re d o m inan tIM R d ire c tp a th
S c a tte r o f IM Rd irec t p a th
D iffra c tion
S -b a nds a te llite s ig na l
S -b a n d IM Rs ig na l
E IR P TE IR P S
S c a tte r
L o S
� The satellite signal can occasionally experience deep and long fades (overpasses, trees, tunnels,..) . Unlike terrestrial networks, it is not economical to mitigate these effects by sheer increase of power.
� It is not economical to deploy terrestrial gapfillers everywhere.
� Time diversity is the solution.
Slide 12 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
MAIN CONFIGURATIONS CHOICES
� Waveform : SH-A (OFDM-sat/OFDM-ter) or SH-B (TDM-sat/OFDM-ter)
SH-A allows SFN operation between satellite and terrestrial (sat+ter).
SH-B cannot offer SFN (sat+ter) but more resilient to non-linearity. Requires at least 2 demodulators, but receivers can work in both SH-B network and SH-A network.
� Frequency : SFN (sat+ter) or MFN
SFN maximizes global capacity, easier for handover. Can be used only with SH-A.
MFN allows independent optimisation of satellite and terrestrial PHY parameters. Allows also independent optimisation of clusters of terrestrial transmitters and/or staged deployment of gapfillers.
� Physical Time interleaver : Short (~ 200-300 ms; Class-1 ) or Long (~10-30 sec; Class-2 )
“Short” is adapted to terrestrial propagation, requires less memory (4 Mbits)
“Long” is necessary for certain satellite conditions (long fades). Necessitates ~256 Mbits (Class-2)
“Long” can be configured to contain “Short” as a compatible sub-set. Compatible means receivers with limited memory (Class-1) can operate with “Long”, but with margin degradation.
� Link-layer FEC : MPE-IFEC extends MPE-FEC to provide protection against multi-burst losses.
Can be applied service-by-service
Slide 13 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
DO I HEAR ANY BETTER OFFERS ?
� Use state-of-the-art & proven waveform for multipath channels
� Use state-of-the-art & proven waveform for satellite nonlinearity
� Use state-of-the-art & proven FEC
� Optimised for Land Mobile Satellite channels
� Allows Single Frequency Network operation
� Allows receiver battery conservation
� Allows Statistical Multiplexing
� Allows Hierarchical modulation (OFDM only)
� Allows per-service differential protection (at Link-Layer)
� Co-existence with 2/3G
� Spectrum efficient
Slide 14 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
AT THE CONVERGENCE OF 3 WORLDS
SATELLITE
SATELLITE
BROADCASTER MOBILE OPERATOR
Slide 15 Nghia PHAM ESA WORKSHOP – Ground Segment Technology, Nordwijk, 5/6 June 2008
SHOULD I ENTER THIS….?
S-TIMI" 相符的内容相符的内容相符的内容相符的内容
BIFS or LASeR?
DRM or Smartcard?
MBMS TDD HSDPA LTE
3GPP DIMS? JSR 272? HisTV ?
ISMACryp?