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DIGITAL BROADCASTING VIA SATELLITE USING IP TECHNOLOGY FOR EDUCATION

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... C DVB S Comparison of various standards VSAT VSAT means Very Small Antenna Terminal It is small fixed earth station located on earth surface. – PowerPoint PPT presentation

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Title: DIGITAL BROADCASTING VIA SATELLITE USING IP TECHNOLOGY FOR EDUCATION


1
DIGITAL BROADCASTING VIA SATELLITE USING IP
TECHNOLOGY FOR EDUCATION
2
Digital Video Broadcasting ( DVB )
3
Introduction
What is DVB ?
  • Digital Video Broadcasting (DVB) is a set of
    standards for Digital Television
  • Dealing with transmission of digitized audio,
    video and additional information.
  • i.e. Multimedia

4
Why DVB in place of Analog Transmission
  • Deficiencies of analog TV transmission
  • Bad quality if signal gets weak
  • Inefficient use of scarce frequency bandwidth
  • Expensive transmission infrastructure
  • Bad mobile reception
  • Addition of modern services nearly impossible

5
  • Advantages of DVB
  • High quality
  • Mobile reception possible
  • Newly added services
  • Multimedia Home Platform (MHP)
  • E-Commerce, E-Banking
  • More efficient usage of frequency bandwidth
  • Advantage for content providers

6
  • Disadvantages of DVB
  • Incompatible to old analog television
  • Incompatibilities in-between different DVB
    instances
  • Fails abruptly in case of insufficient reception
    quality
  • Slower zapping speed
  • Receiver must synchronize to new transport stream
    after changing channels

7
  • Different possibilities of DVB transmission
  • Via satellite DVB-S
  • Via cable DVB-C
  • Via terrestrial transmission DVB-T
  • For handheld receivers DVB-H

8
  • Digital Video Broadcasting using Satellite
    (DVB-S)
  • Satellite-TV uses geostationary satellites.
  • Satellites relay signals received from the
    ground (uplink)
  • using transponders (downlink)
  • Frequency spectrum 10.7 12.75 GHz
  • Since solar power is used, transmission power is
    quite low
  • Each transponder transports multiple analog
    and/or
  • digital TV channels using Time-division
    multiplex
  • DVB-S uses Quadrature Phase Shift Keying (QPSK)
  • for modulation

9
  • Digital Video Broadcasting using Co
    Axial Cable ( DVB-C )
  • Television signal transmitted via broadband
    coaxial cable
  • Cable Head-Ends inject the modulated signal into
    the cable segments Each cable segment
    serving around 500 1000 users
  • Broad frequency spectrum
  • Modern cable networks incorporate a feedback
    channel capability
  • Sometimes problematic lower frequencies can be
    disturbed, line sharing among users, cable
    modem signals can influence DVB-C quality
  • Uses QAM as modulation system
  • QPSK would also be possible, but result in lower
    spectrum efficiency

10
  • Digital Video Broadcasting using Terrestrial
    (DVB-T )
  • Terrestrial transmission of television
  • Transmitted via ground infrastructure like
    transmission towers, etc.
  • Can be difficult and cost-intensive to cover
    whole countries (landscape dependent)
  • DVB- T should be receivable nearly everywhere
  • Stationary and portable (mobile)
  • Depending on reception, small antennas can be
    sufficient (e.g. on cars)
  • DVB-T must cope with 8 MHz bandwidth channels
  • Somewhat limits achievable quality
  • Depending on current content, bandwidth can be
    temporarily increased Onto the cost of other
    channels in the same bouquet
  • Allows only a few digital TV channels in one
    bouquet.
  • Terrestrial transmission is prone to multipath
    propagation

11
Functional Block Diagram of a DVB S
Satellite Channel
DVB S Channel Adaptation
MPEG Encoding Unit
12
MPEG Encoder This Unit can take in several
compressed video channels. All data is compressed
to produce a single MPEG data block of size 188
bytes. MPEG Encoders now exist that can compress
together up to 10 regular video
channels. Energy Dispersal The MPEG blocks are
shuffled to improve the output spectrum. Outer
Code-Reed Solomon A (204/188) Reed Solomon Code
is applied to the data. This code is capable of
correcting 8 errors.
13
Interleaving The data is then interleaved
(convolutional interleaver )  Inner Code The
data is then convolutionally coded depending on
the transponder size and channel quality desired.
QPSK Modulation This single carrier is now
QPSK modulated.
14
Comparison of various standards
DVB S DVB C DVB T
Transmission Satellite Cable Terrestrial
Standard ETS 300 421 ETS 300 429 ETS 300 744
Frequency Bands C and Ku 10.7 12.75 GHz VHF I, VHF III, UHF 302 470 MHz VHF III and UHF 174 790 MHz
Modulation QPSK ( 4 PSK ) QAM 16, 32 or 64 QAM COFDM 16 or 64 QAM
Spectrum Bandwidth 27 - 33 MHz 7 8 MHz 7 8 MHz
User Data Rate 38.015 Mbps 38.015 Mbps 14 24 Mbps
Max. Data Rate 55 Mbps 27 41 Mbps 39 Mbps
15
VSAT
16
  • VSAT means Very Small Antenna Terminal
  • It is small fixed earth station located on earth
    surface.
  • It Consist of two units
  • Indoor unit ( IDU )
  • Outdoor unit ( ODU )
  • an antenna of 6 11 meter in diameter
  • Normally works on Star or Mesh topology.
  • Mostly used topology is Star Topology.

17
VSAT system ( ODU )
18
VSAT IDU
LAN LED P.C connected to Vsat
TRANSMIT LED SIT able to Transmit to HUB
RECEIVE LED SIT able to receive outroute
SYSTEM LED SIT is working fine
POWER LED SIT is getting Power
19
  • VSAT Access Technologies
  • Time Division Multiple Access (TDMA)
  • Frequency Division Multiple Access (FDMA)
  • Code Division Multiple Access (CDMA)
  • Demand Assigned Multiple Access (DAMA)

20
  • VSAT Advantages
  • Reach
  • Can be access any where
  • Reliability
  • Up time up to 99.5
  • Time
  • Less time to install
  • Network Management
  • Easy maintenance of a network
  • Maintenance
  • Easy fault finding and trouble shooting
  • Flexibility
  • More VSAT can be added easily
  • Cost
  • Compare to lease line resultant cost is less

21
EDUSAT
22
Indian Space Research Organization has pioneered
the use of front line space based communication
technologies in the field of education and
development. ISRO launched EDUSAT, a satellite
meant exclusively for education sector, on
September 20, 2004.
23
Technical Specification for EDUSAT ( GSAT- 3 )
24
  • 5 Spot Beams in
  • Ku Band
  • 1 National Beam in Ku Band
  • 1 National Beam in Ext C Band
  • (6 Channels)

25
EDUSAT Network Layout
26
(No Transcript)
27
(No Transcript)
28
Block Diagram of SIT
29
TECHNOLOGICAL CAPABILITIES OF EDUSAT
30
Video Conferencing
Technological Possibilities
Effective Multimedia Delivery
31
EDUSAT TECHNOLOGY
  • VIRTUAL CLASSROOM
  • VIDEO ON DEMAND
  • DATABASE ACCESS
  • ON-LINE ADMISSION
  • ON-LINE EXAMINATION
  • RADIO NETWORKING

32
VIRTUAL CLASSROOM CONFIGURATION
EDUSAT
REMOTE CLASSROOMS
TEACHING END
RETURN LINK (Live Voice/ Voice Mail/Text Message)
TEACHERS/STUDENTS
33
VIDEO-ON-DEMAND (VOD) NETWORK CONFIGURATION
EDUSAT
SATELLITE INTERACTIVE TERMINALS (SITs)
VIDEO SERVER
CEC/EMRC/CIET
TEACHERS/STUDENTS
34
DATA/LIBRARY ACCESS NETWORK CONFIGURATION
EDUSAT
SATELLITE INTERACTIVE TERMINALS (SITs)
MULTIMEDIA
TEACHING MATERIAL
LIBRARY/DATA SERVER
TEACHERS/STUDENTS
35
RADIO NETWORKING CONFIGURATION
EDUSAT
AUDIO SERVER
STUDIO
COLLEGES/STUDY CENTRES
36
EDUSAT in TELEMEDICINE EDUCATION In
collaboration with ISRO
37
1 Lakh patients treated
38
ISROs Telemedicine Program - Thrust Areas
  • Providing Technology and Connectivity
  • Remote/rural hospitals and specialty hospital
  • Continuing Medical education (CME)
  • Mobile telemedicine units
  • Disaster Management Support (DMS)
  • Integrating with village resource
    centers/information kiosks

39
Access of EDUSAT using software program TRAIN
NET
40
(No Transcript)
41
Conclusion
At concluding we can say that EDUSAT will provide
the best service to the country in the field of
education and other applications to the remote
areas of the country.
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