professional equipment broadband systems ip software satellite distribution of dtv and mobiletv...
TRANSCRIPT
Professional Equipment
Broadband Systems
IP Software
Satellite distribution of DTV and MobileTV content.
Presented at: Regional Seminar on DTV Broadcasting, Algiers, December 2007
By: Joost Verbrugge
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Contents
• Why Digital Terrestrial TV ? • The way to Analog Switch Off• Single Frequency Networks• The primary distribution network• Why Satellite ? • Application examples• What about Mobile-TV ?
– What is mobile TV ?– Technologies and standards– Primary distribution of content for Mobile-TV
• Conclusions
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Why Digital Terrestrial TV ?
• From analog to digital TV transmission: why?– Robustness of the signal– Constant picture quality– New applications come in digital version only:
• Interactivity • High definition TV• Mobile TV
– More efficient use of spectrum (4-6 times)– Savings in operational cost of network
• Competitive with Cable, DTH, TelcoTV (IPTV)
– Availibility of low cost Set Top Boxes/receivers.
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The way to Analog Switch Off• Some definitions
– Standards • DVB-T, ATSC-8VSB, ISDB-T
– Digital Switch-0ver (DSO)• The start of digital transmission for public television
– Analog Switch-Off (ASO)• The end of analog transmission for public television
– Simulcasting • Period of simultaneous analog and digital transmission
of the same TV programming• This period allows viewers to convert from analog to
digital reception (Set Top Box, decoder, antenna)
– Digital Dividend • Savings in spectrum thanks to conversion to digital
transmission; can be re-used/sold for new applications. • Remember: dividend comes after investment...
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The way to Analog Switch Off
Every country has to decide on timing of– Step 1: decide on standard (DVB-T ?)– Step 2: Digital Switch Over plan (DSO)
• Including Frequency Plan, SFN/MFN, Capex plan...
– Step 3: Decide on Analog Switch Off date (ASO)– Step 4: Build network with 95+% coverage
• Simulcasting from DSO to ASO
– Step 5: Decide on spectrum allocation after ASO– Step 6: Grant licences/spectrum for new services– Step 7: ASO
• start of savings, start of new income
– Step 8...88: license new services including mobileTV, HDTV, multiplexes of above, (Wimax), (DAB), ...
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Single Frequency Networks
• Digital TV using COFDM allows SFN operation– One frequency for all transmitters in large area– Saves on frequencies used– Allows other (better) network topologies
• More transmitters with less power to cover area
• Requirements for SFN operation: – Each transmitter must radiate:
• On the same frequency• At the same time• The same data bits
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Single Frequency Networks
• Requirements for SFN Operation: implementation– Frequency and Time reference (e.g. GPS)– MIP specification and insertion by ‘SFN adapter’– Carefull design of network:
• Guard time selection defines maximum distances between transmitters
• Power levels should avoid intersymbol interference (noise)• Primary distribution network must deliver signal multiplex
intact (bit by bit identical) and on time at transmitter.
• Local content insertion per SFN area (market)– Allows local advertising in local language– Allows re-use of frequencies in non adjacent areas
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Single Frequency Networks
SFN 1
SFN 1
SFN 1
SFN 3
SFN 3
SFN 3
SFN 2
SFN 2
SFN 2
SFN 1
SFN 1
SFN 1
SFN 2
SFN 2
SFN 2
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
DVB-H
Local markets served by several SFN’s
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The primary distribution network
• What? : – The Primary Distribution Network brings the signal
stream (multiplex) to all transmitters in the DTT network.
• How? :– Terrestrial :
• fibre with SDH, ATM, ...protocols• Private IP based networks
– Micro Wave : Point to point links– SATELLITE based primary distribution network– Combination of above (redundancy)
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The primary distribution network
• Why Satellite ?
– Fast and reliable deployment possible• Once ‘on air’, the complete footprint has access to signal
– High and constant signal quality over entire footprint– Integrity of original signal stream (SFN !)
– No (re)multiplexers in network
– Constant delay, no (variable) ‘latency’ (SFN!)– Full redundancy possible – Less or no service interruptions in primary network
– No fiber breakdown, no power supplies, no equipment in signal path, ...
– Long term committment possible (opex cost control) – Scalable with limited Capex (investment cost)
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The primary distribution network
• Why (not) Satellite ?: challenges and solutions:
• Cost ? (perception of cost...?)– Initial (opex) cost an be an issue (first DSO phase)– Break-even between 50 and 100 sites– Opex cost under control by long term agreements – Save cost by efficient modulation schemes (S ->S2)
• Availability ? – New possibilities coming (Arabsat, NileSat, ...)– Ground equipment standardized from multiple
vendors
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The primary distribution network
• Why Satellite: network operator considerations:
– Fast network deployment possible– SFN operation easy to implement– Flexibility in network build-up
• Additional repeaters can be added when/where needed• No additional (distribution) cost when adding sites.
– Full coverage (ASO!) at limited cost– Most equipment centralized at one site (playout/uplink)– Network management & control easier/lower cost– Limited maintenance (transmitter sites only)– Only one service operator
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Application examples:
without COFDM + 3rd party Transmitter
+ 3rd party amplifier
Horizon - Amplifier
Integrated tranceiver possibilities:
Small power gap-filler
Medium power tranceiver
High power transmitter
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Application examples:
SFN 1
SFN 1
SFN 1
SFN 3
SFN 3
SFN 3
SFN 2
SFN 2
SFN 2
SFN 1
SFN 1
SFN 1
SFN 2
SFN 2
SFN 2
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
DVB-T
Local markets served by several SFN’s
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Application examples:
ASICONCEN-TRATOR
P1a, P2a, P3a,...
ASI TSa
P1b, P2b, P3b,...
ASI TSb
P1c, P2c, P3c,...
ASI TSc
P1d, P2d, P3d,...
ASI TSd
ASIDECON-CENTRA-TOR
P1a, P2a, P3a,...
ASI TSa
P1b, P2b, P3b,...
ASI TSb
P1c, P2c, P3c,...
ASI TSc
P1d, P2d, P3d,...
ASI TSd
MPEG/DVB/ATSCTransmission channel
Proprietary Transport stream
Exact copies
ASI TSx = MPEG Transport Stream x on ASI Px = Program x
Concentrator Deconcentrator for DVB-T (Newtec-Technology):
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Application examples:
Local market content insertion
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Application examples: • Basic primary distribution concept
One transport stream includes national and
all local channels
National and local
feeds
Encapsulator into TS
Satellite modulator
COFDM &
up conv
Sat demod
Local drop
Transmitter site
Ampli & filter
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Application examples:
Central HubDVB-H mod
Sat demod Local drop
DVB-H SSPA
Remote site
Broadcast TS
Sat3play modem
NM station
Management plane
S3Play Hub
Network monitoring & control
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What about Mobile-TV ? What is Mobile TV ?
Old dream of “Television wherever you go”
Casio 1983
Sony 1990
Sinclair 1977
RCA 1963 Seiko 1984 Sony 1982
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What about Mobile-TV ?
• What is Mobile TV anno 2008? • TV on your mobile• TV in your car• TV on the go (PSP, iPod, etc...)
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What about Mobile-TV ?
• Dream of “Television wherever you go”
Mobile TV at this moment is: • High quality TV for small screens on the move• Broadcast network with indoor coverage• Large number of channels instantly available• Choise of handsets, in-car sets, etc. ...• Personal Phone + TV integrated• Includes ESG, radio, VoD possibilities• Provides regional/local content (?)
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What about Mobile-TV ?
• Dream of “Television wherever you go”
Still some challenges to face/solve:• Agree on standards• Have frequency spectrum available• Combine telecom and TV worlds to realise
personal TV handset.• Create working business models• Adjust regulation (must-carry, protection of
minors, content rights, etc...)• Build/adapt transmission networks• Increase battery lifetime
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What about Mobile-TV ?Technologies and standards: overview
Existing
• S-DMB• T-DMB• DVB-H• MediaFLO• DAB-IP• ISDB-T
Bold = Satellite Delivery
Announced
•CMMB•DVB-SH•MBMS•A-VSB •ATSC-M/H•Wimax
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What about Mobile-TV ?Additional information on standards and technology: • DVB info on www.dvb.org and www.dvb-h.org • Standards on www.etsi.org • Comparison of bearer technologies by
bmco-forum on www.bmcoforum.org • Link budget paper on www.bmcoforum.org • Paper on MediaFLO at www.floforum.org
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Delivery of Mobile TV by Satellite
What ?
• Direct reception of satellite signal by handset• Used in Korea (S-DMB)• Announced in China (CMMB), Europe (DVB-SH) and
Middle East (S2M)• All systems use dedicated beams in S-band• All systems need terrestrial transceivers for indoor
reception in S-band, synchronized with direct beam.• Tranceivers need signal stream from primary
distribution (=satellite) ahead of direct beam.
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Delivery of Mobile TV by Satellite
• Advantages– Country wide coverage from day 1– Uniform reception performance– S-band: antenna diversity techniques possible
• Disadvantages:– Dedicated satellite needed (+back-up?)– No direct indoor reception possible
• Challenges: – Dense terrestrial network needed for indoor reception– S-band: propagation more difficult for indoor than UHF/L– Limited number of handsets available (except Korea?)
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Primary distribution for mobile TV
What ?• Signal distribution to transmitter towers, gap-
fillers, transceivers for mobile TV• Needed with all standards/technologies• Identical stream to all transmitters (SFN)• Mostly Ku-band, C-band also possible
Alternatives ? • Terrestrial distribution over fiber• Existing backbones, ATM, IP-networks• Microwave
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Primary distribution of mobile TV
• Advantages– Rapid deployment/extension of network possible– Most cost-effective for larger number of towers (>100)– Easy implementation of SFN network– Easy network management possible
• Disadvantages– (perception of initial) cost
• Challenges– Integrated transceiver availability– Local content solutions – Network management solutions– Back-up questions/solutions
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Primary Distribution network :
• Differences DTT versus Mobile TV : • For DVB-T versus DVB-H:
– Technology: almost identical– Network: requirement for indoor coverage !!!
• More signal strength needed • More tranceivers/gapfillers needed (deep indoor)• SFN operation required
– Satellite requirements for distribution:• Less bandwidth for DVB-H bouquet (5-8 Mbit/sec)• More gapfillers for DVB-H -> smaller receiver dishes
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Application examples: DVB-T and H combined
Combine multiple bouquets (=multiplexes)
in one saturated transponder
DVB-H can be added in second phase
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Conclusions for Mobile-TV :
• Good Mobile-TV reception ...– Means good indoor coverage …– Means many transmitters (1000+…) transceivers gap-fillers – Means Single Frequency Network Operation…– Means exact frequency/timing requirements…
• …means Satellite distribution to transmitters !
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Conclusions for DVB-T and H: • Digital Terrestrial TV needs large broadcast
network with full (outdoor) coverage to allow ASO. (50-500 sites)
• Mobile TV needs broadcast network with good outdoor and indoor coverage. (1000+ sites)
• Satellite distribution is cost effective for 100+ sites and allows rapid deployment of network
• Flexible local content distribution possible• SFN and MFN operation possible• More channels/lower cost with DVB-S2• Centralized monitoring and control possible• Solutions for different standards, markets.
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Satellite distribution of Digital-TV and Mobile-TV content
Thank You !Questions ?
Mail to : [email protected]