a seminar presentation on satellite communication & DTH with all the key point covered under this ppt with a small video attached in one of the slides inside this presentation.

1. &
DTH
PRESENTED BY :-
Siddhartha gupta
EC-3rd yr
1402931156

2. TOPICS OF PRESENTATION
INTRODUCTION
WORKING
TYPES OF ORBITS
ADVANTAGES
DISADVANTAGES
COMPONENTS OF DTH
WORKING OF DTH
SET TOP BOX
APPLICATIONS
CONCLUSION
LATEST SCENERIO
REFRRENCES

3.  A satellite is simply any body
that moves around another
(usually much larger) one in a
mathematically predictable path
called an orbit.
OR
A satellite is a solid object which
revolves around some body due
to the effect of gravitational
forces.
 The first man made satellite with
radio transmitter was in 1957
 There are about 750 satellites in
the space, most of them are used
for communication

5. 18-Sep-17 satellite communication 5
What is Satellite
communication ?

6.  Two Stations on Earth want to communicate through
radio broadcast but are too far away to use
conventional repeater.
 The two stations can use a satellite as a relay station
for their communication
 One Earth Station transmits the signals to the satellite.
Up link frequency is the frequency at which Ground
Station is communicating with Satellite
 The satellite Transponder converts the signal and
sends it down to the second earth station. This
frequency is called a Downlink frequency

8. 18-Sep-17 satellite communication 8Wired satellite communication
 BASIC BLOCK DIAGRAM OF SATELLITE
COMMUNICATION

9. TRANSPONDER

10. C BAND:-  C-band is the most
common frequency
spectrums used by
today’s satellite.
 C-band satellite
transmission occupy
The 4 to 8GHz frequency
Range.
 C-band antennas is
approximately 2-3
meters in diameter.

11.  KU-BAND :
 KU-band satellite
transmission occupy the
13 to 18 GHz frequency
range.
 KU-band antennas can be
as small as 18 inches in
diameter.
 these very high
frequency transmission
mean very small wavelenghts
and very small diameter
receiving antennas.

12. Types of orbits…
 Geosynchronous
 Same rotational velocity as
earth
 Maintains position relative
to earth
 Altitude - 35 786 km
 Velocity - 11 300 km/hr
 Asynchronous
 Much lower altitude = much
higher velocity
 Position over earth
constantly changing
Contd….

18. DIRECT TO HOME SERVICE(DTH)

19. 19
What is DTH ?
DTH is defined as:
 The reception of satellite programs with a
personal dish in an individual home.
 DTH does away with the need for the local
cable operator and puts the broadcaster
directly in touch with consumer .
 A wireless digital audio / video service is
delivered through satellite.

20. 1996 : DTH services were first proposed in India
2000: DTH was allowed with new policy
The operators were required to setup earth stations in
INDIA within 12 month for getting license of broadcasting
whose cost was $2.14 million and will be valid for 10 years.

21. MAIN COMPONENTS OF DTH:-
 Broadcasting center
 Satellites Encoders
 Multiplexers
 Modulators
 DTH receivers.
 The broadcast centre is the main part of the whole system. It
is from the broadcast station that the signals are sent to the
satellites to be broadcasted. The broadcast station receives the
signals from various program channels.

22. CONTD ...
 The satellite receives the signal from the broadcast
centre and compresses the signals and makes them
suitable for re-transmission to the ground.
 The DTH providers give dish receivers for the viewers
to receive the signal from the satellites. There may be
one or multiple satellites that send the signals at the
same time. The receiver receives the signal from them
and is passed on to the Set Top Box [STB] receiver in the
viewer’s house.
 The STB receiver changes the signal in a form suitable
for our television and then passes it on to our TV.

23. A DTH ALSO CONSISTS OF :-
 MINIDISH ANTENNA
 LNBF
 COAXIAL CABLE
CONNECTOR
SET TOP BOX Minidish antenna
LNBF
CONNECTOR

24. LNBF
 LNBF is a part of a satellite antenna which is positioned
In front of the dish to recieve the signal and converts the
Signal to be carried by cable to the reciever.
 low noise block down converter is the antenna of a
what is commonly called the parabolic satellite dish
commonly used in satellite TV reception.

25. SET TOP BOX
• A set top box(STB) or
Set top unit (STU) is a
Device that connects to
A television and an
External source of signal,
Turning the signal into
Content which is then
Displayed on the
television
Screen.
 i/p voltage range:-
90-250V AC
 freq connectors:-
50Hz ± 5%

26. ENC1Enc1
ENC 22 MUX 
QPSK
modulator


Service uplinked
To satellites
Services
downlink via
receive satellite
dish and fed
into STB
Content “on demand” servers
BASIC BLOCK DIAGRAM OF DTH:-

27. OPERATION ...
 The block diagram of DTH TV system is divided into two
sections:-
1) OUTDOOR UNIT
2) INDOOR UNIT
 OUTDOOR UNIT
• The outdoor unit consists of:-
1) THE PARABOLIC REFLECTOR ANTENNA
2) LOW NOISE AMPLIFIER (LNA)
3) CONVERTER

28. CONTD...
• The receiver antenna is a parabolic reflector horn antenna
which is directed directly to the satellite to receive the signal.
• the received signal from satellite by the antenna is applied
to the low noise amplifier(LNA) which is a wide band amplifier.
• LNA amplifies all the frequencies received from the antenna
and applies them to a converter. The second input to this
converter is from the local oscillator 1.
• the converter output consists of a UHF signal having a
frequency range from 950-1450 MHZ with a bandwidth of
500MHZ.
• the output of converter is applied to the RF amplifier.

29. INDOOR
 It consists of a RF amplifier which is applied to a channel
selector to select the desired channel with the help of a mixer
& local oscillator too.
 An IF frequency of 70MHZ is produced,
 The RF amplifier applied these to video-audio detector which
separates the video , audio & synchronous pulses.
 the TV receiver then works as usual.
 A DBS(directly broadcast satellite ) concept is used in DTH system.

30. 30
0.06 0.18 0.75
1.925
4.8
9.8
15
20.9
26.1
30.4
33.8
36.2
37.6
0
5
10
15
20
25
30
35
40
2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
Year
Subscribers(Millions)
GROWTH OF DTH USERS
2007 to 2015…Growth of 683 %

31. DTH Vs CABLE TV
DISH TV(DTH) CABLE TV
 Dish networks features,
HD, CD sound superior
picture quality with huge
nos of channel access.
 dish TV has remote
Geographical access with
Limited installation.
 special features –
recording, play games ,
study ads for childrens,
and language home
tutorial packages.
 Average accessed quality
of sounds & pictures ,limited
number of channel accessed.
 cable for subscriber is a
limited to wire but major to
the supplier with huge
installation.
 cable TV had manual
access with least features but
with cable modem net.

32. ADVANTAGES OF SATELLITE OVER TERRESTIAL
COMMUNICATION
 The coverage area of a satellite greatly exceeds that
of a terrestial system.
 Transmission cost of a satellite is independent of the
distance from the centre of the coverage area.
 satellite to satellite communication is very precise.
 Higher bandwidths are available for use.

34. ADVANTAGES OF DTH:-
 With DTH service we can get direct television services to
our home which can be situated anywhere.
 As the DTH service is based on satellite and there is not
requirement of wires signal like cable TV connection
anywhere in the country.
 DTH also gives us the best sound and picture quality.
 With DTH service we can select the channel programs as
our choice.
 We can pay the subscription fee online through
net banking , voucher recharge or credit card.

35. DISADVANTAGES OF DISH TV(DTH):-
 During heavy rain we cannot get a clear signal. This is
the major problem for the subscribers of DTH service.
 Another major problem is that we cannot change our
service provider. Eventhough , if any service provider
gives us service badly we cannot shift to another
as the set top box settings are only linked with the same
service provider . If we want to change the service
provider then we should need to pay additional cost
to buy new set top box from new service provider.

36. CONCLUSION:-
 DTH has made the hopes of the people of rural areas
to come true.
 DTH service in India is in initial stage delivering
only TV broadcasting.
 It provide the wide thinking of rural people which
helps to develop the culture of society ..

37. REFRECNES:-
 https://www.wikipedia.com
 https://www.linkedin.com
 http://onlinelibrary.wiley.com
 http://www.academia.edu
 https://www.ieee.org
 https://www.TUTORvista.com