Neeraj Shukla presented on Direct-To-Home (DTH) technology at Subharti Institute of Technology and Engineering. DTH provides television services directly to subscribers via satellite, without needing local cable operators. It consists of a dish antenna, TV set, set-top box, and coaxial cable. Programming sources uplink signals which are received by the dish antenna and broadcast to subscribers, bringing information and entertainment into homes across urban, rural, and remote areas. While DTH overcomes limitations of cable TV networks, it can be interrupted by weather conditions or dish movement.

1. Seminar Coordinator :Mr. Dharmendra Verma
Presented By :Neeraj Shukla
( 1001131029 )
( E.C. 3rd Year )
Department Of Electronics and
Communication
Subharti Institute Of Technology And

2. •
Introduction
• Specifications and Features
• Working
• Components
• Benefits and Limitations
• Conclusion

3. DTH stands for Direct-To-Home
The Direct-To-Home (DTH) service is a digital satellite service that
provides television services direct to subscriber.
DTH does away with the need for the local cable
operator and puts the broadcaster directly in touch
with consumer.
The installation of a DTH Television consists of :
•
A Dish Antenna (60 to 90 cm) in diameter
•
A Conventional TV set
•
Set top box
•
Coaxial Cable between dish and set top box

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The frequencies for DTH vary from region to
region but it lies in Ku band of microwave .
Uplink frequency range – 17.3 to 17.8 GHz
Downlink frequency range – 12.2 to 12.7
GHz
An electronically controlled polarizer is used
at receiving terminal for converting circularly
received polarized signal to linearly polarized
signal.
A DTH – TV satellite carries up to 32 high
power Transponders.
Digital TV signals are transmitted as 20 Mbps
QPSK signal occupying about 27 MHz of
transponder bandwidth for a single channel.
MPEG-2 format is used for video
compression.

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Some of the features of DTH service are as following:
DTH offers better quality picture than Cable TV.
DTH can reach remote areas where terrestrial transmission and cable TV
have failed to reach.
DTH also allows for interactive TV services such as movie-on-demand,
and e-mail.
In DTH, the payments will be made directly by the subscriber to the
satellite company offering the service.

8. 
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The programming source are
simply the channels that
provide programming for
broadcast.
Satellite TV provider get
programming from two major
source: International
Channels(such as HBO,ESPN
& CNN)& various Local
Channels(Sahara TV,
Doordarshan ).
These channels usually have
a distribution center that
beams their programming to
a geostationary satellite.

9. Multiplexer
Encoder
(MPEG-2)
Modulation
Encryption
Transmission

10. Dish
Antenna
LNB Feed
system
Receiving
Terminal
Set Top Box
Interface
Cable

11. 
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A satellite dish is just a special kind of antenna
designed to focus on a specific broadcast
source. The standard dish consists of a
parabolic (bowl-shaped) surface and a central
feed horn. To transmit a signal, a controller
sends it through the horn, and the dish focuses
the signal into a relatively narrow beam.
The dish on the receiving end can’t transmit
information; it can only receive it. The
receiving dish works in the exact opposite way
of the transmitter.
When a beam hits the curved dish, the parabola
shape reflects the radio signal inward onto a
particular point, just like a concave mirror
focuses light onto a particular point.
The curved dish focuses incoming radio waves
onto the feed horn.

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The central element in the feed horn is low noise block-down converter.
Block-down convertor (so called because it converts a whole band or
‘block of frequencies’ to a lower band) i.e. it converts the 12.2 to 12.7 GHz
band to 950 to 1450 MHz
An LNB sits on the end of an arm and faces the parabolic reflector(dish)
which focuses the signals from a satellite into the feed horn of the LNB.

13. Universal LNB
Twin Output LNB
Quad Output
LNB

14. › The basic Set Top Box (STB) takes the signal from the satellite dish and
converts it into a signal that can be used by a TV, sound amplifier, etc.
› STBs can act as a gateway between a television or PC and telephone,
satellite, terrestrial or cable feed.
› The STB also accepts commands from the user and transmits these
commands back to the network operator.

17. 
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Cost effective communication,
information and entertainment to all.
Small size terminal can provide up to
4000 channels and 2000 radio
channels through a click of button
and thus bring world’s information,
news entertainment to your home.
DTH services bypasses mediators and
thus content provider comes with
customer directly.
DTH services are transparent
providing digital quality video, audio,
radio, and IP to all at equal prices and
other benefits with reliability.

18. •
Under unfavourable climatic conditions the service remains
unavailable.
• The service is interrupted in case if the direction of dish is
disturbed.
• Transmission gets interrupted due to sun outage.

19. Satellite
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Geostationary satellite plays an
important role for DTH system.
They are positioned at an exact height
of 36,000 km above earth.
They solve the problem of range and
distortion by transmitting broadcast
signals.
Polarization
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It is a way to give a specific direction
to a transmitted signal.
Signal transmitted by satellite can be
polarized as linear(horizontal and
vertical) or circular(left hand or right
hand) .

20. Direct To Home Technology connects urban , rural and
remote areas of the country and provide desire information,
communication, education and entertainment at the click of
button.

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www.wikipedia.com
www.scribd.com
‘Wireless Industries Jr.’ IEEE Computer
Magazine, July 2008
www.authorstream.com