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DTT : general technical points
François-Xavier Georgetin charge of technical affairs
Direction du Développement des Médias([email protected])
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Table
DTT : general overview?
Technical aspects
How marketing scenario is influencing technical points
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DTT general overview
Digitalization general trend in broadcasting better quality less expensive transmission more numerous services
What is DTT Digitalization of terrestrial hertzian waves
3 historical broadcasting transmission means terrestrial satellite cable
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Allocation of each transmission vector
Allocation different depending on each country broadcasting and industrial policy breakdown of the population
multi-equipment in households : One third of households with more than one TV receiver US and japan : about 3/4 UK : 37 % (24 % more than 3 )
For example France8%
6%
9%
5%
72%
Only terrestrial
Satellite & terrestrial
Satellite
Cable
Cable : only terrestrial channels
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DTT : essential to digitalization
In a country where terrestrial is a main mean of reception DTT is one (if not only ?) way to provide digital services to every body at large scale in short time
In completion of digital cable and satellite Reusing of analogical transmission sites feeling of simpleness to take benefit of: plug and play reusing of antenna
low cost of up grading 23 € each household vs 150 € for cable and satellite
adapted to local television (contrary to satellite)
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Basic technological aspects of DTT
spectral efficiency : 6 times more than analogical
spectrum planification with less constraints
isofrequency
transmitters : 20 times less powerful
portability & mobility
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Desavantages compares to cable and satellite
Still expensive transmission cost for one channel between 5 à 10 millions € a year for 80% of people in France (vs
80 anal.) 0,5 million € a year for satellite could be between 2 and 4 millions € for cable (but different model)
low bit rate available 6 mux 150 Mbit/s vs 1 Gbit/s for cable and for satellite
very low real interactivity
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Objectives pursuited with DTT
In France decision has been made :DTT has to be launched
To complete digital offer
To spread free TV offer
To stand for cultural diversity
To stand for consumer electronic industry
more efficient management of radio spectrum
in second term : switch off
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DTT : an old technology out of date ?
Recent controversy in France real problem for some people the heavy legally framework
DTT vs xDSL condition to be available for people business plan
real debate broadcasting network vs commuted networks MPEG 2 vs MPEG 4
Broadcasting lays on settled technology reliability cost for consumer
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Detailed technical aspects to be take into account
Spectrum management
transmitted signal specifications
reception antenna set up boxes
Workshop in France since 2002 National regulatory authority broadcasters industrialists
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Spectrum management
Planification switchover : analogical and digital avalability of spectrum international coordination to define objectives to be reached
what kind of coverage (macro / micro cellular) fix portability mobility
Consequences induced re-arrangment of analogical spectrum
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Signal specifications 1
DVB-T standardisation adopted at european level new electronic communication packages and standardisation scrambling algorithm
API new electronic communication packages and standardisation MHP
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Signal specifications 2
specific information transmitted list of channels name further information on programs
parental control epg
crossed information interoperability of set up boxes up-grading of set up boxes
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Reception
Transmitted is one thing, to be able to receive an other UK 1998
Antenna
collective antenna
Set up boxes
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Antenna
Antenna vs portability
2001 Simavelec study for France : individual household
Coût d'intervention par habitat individuel
68%11%
18% 3%0 F
< 140 €
< 275 €
< 380 €
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Collective antenna
Coût d'intervention par foyer
52%43%
5%
0 F
<140 €
<160 €
Portability must carry rules 2001 Simavelec study for France : collective antenna
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Set up boxes
Availability in reatil market Sp UK
price under 100 €
free to air vs pay TV
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Set up box specifications
Consumer elctronic industry set up boxes integrated digital TV
specific model for certain country extra functions
parental cost EPG
API
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Experimentations
Technical validation
live experiments before launching signal reception : portability compatibility with analogical channels compatibility with cable antenna set up boxes
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Switch off
goal to be reached within reasonnable terms
marketing success
turn over of TV : 10 % a year
continuity of services
different steps
simulcasting
specific helps : compliance with european law as technological neutrality
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Conclusions
Under estimation
real steeple chase with heavy consequences UK SP
Credibility of DTT in a network world Emily ’s aunt ’s reception mean
Big influence of business plan free to air pay TV
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THE END