DTH (direct-to-home) technology provides satellite television directly to homes, bypassing local cable operators. It was first proposed in India in 1996 but was not approved until 2000 due to security concerns. DTH uses satellites to broadcast television signals to small dish antennas in homes. Key components include the broadcasting center, satellites, encoders, multiplexers, modulators, and DTH receivers. DTH offers better picture quality than cable as there is no signal degradation in transmission. Major DTH providers in India include Dish TV, Tata Sky, Big TV, Sun Direct, Videocon d2h, Airtel Digital TV, and DD Direct.

1. A Presentation on
D.T.H (DIRECT TO HOME)
Submitted By :-
Arijit Chakraborty
BETI1EC16002
Electronic & Communication
3rd Year / V Semester
Submitted to :-
Mr. Shailendra Singh Ojha
Asst. Professor
Electronic & Communication

2. DIRECTTO
HOME

3. CONTENTS: -
 Introduction
 History of DTH
 Main Components
 How Does D.T.H Differs Form Cable T.V
 Scenario in India
 Conclusion

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

5. HISTORY: -
o The first person who invented the technology for
DTH was sir ARTHURE CLARLES CLARKE , a
British inventor in late 1946.
o The DTH service was first proposed in INDIA in
1996 , but was not approved due to concern over
national security.

6. CONT…..
o Finally , In 2000 DTH service was allowed and
DOORDARSHAN was first to provide the service to
the consumers from 1st of April ,2000.
o After this other DTH service provider like ZEE and
STAR started pushing hard for DTH service in INDIA
and setup earth station whose cost was 2.15 million and
was valid for 10 years in INDIA.

7. MAIN COMPONENTS OF DTH: -
o Broadcasting centre
o Satellites
o Encoders
o Multiplexers
o Modulators
o DTH receivers

8. NETWORK OF DTH: -

9. CableHead-end
Private Home Private Home
Private Home
DTH Receive Facility :-

10. UPLINK ANTENNA: -
UPLINK satellite dish are very large in size which
provide accurate aiming and increase signal strength.
They are pointed toward specific satellite and frequency
used is specific so that satellite transponder can receive the
signal.
The EIRP (Effective Isotopically Radiate Power ) for the
up link antenna
EIRP = Pt – Lc +Ga
Pt = Power of Transmitter (dBm)
Lc = Line Loss (dB)
Ga = Gain of Antenna (dBi)

11. SATELLITE: -
A typical satellite can have 32 transponder for Ku band (10
Ghz to 18 Ghz ) and 24 transponder for C band (4 Ghz to 8
Ghz).
A typical transponder can have bandwidth between 27
MHz to 50 MHz
The satellite retransmit the signal back to earth in Ku band
and C band frequency.

12. MINIDISH ANTENNA: -
It is a parabolic reflector it receives
the signal and fed to the LNBF
(Low Noise Band Down Converter),
which works as a receiver for signal
transmitted by the satellite.
LNBF
Parabolic Reflector
(60 to 120 cm)

13. SIGNAL RECIVED BY MINIDISH: -

14. LOW NOISE BAND DOWN CONVERTER: -
(LNBF)
It collect the signal from minidish.
It receive the signal form Ku band and down
converter to radio frequency signal.
It amplify and remove the distortion from the
receive signal.

15. BLOCK DIAGRAM OF DTH SYSTEM
Low noise
amplifier
Down
Converter
Amplifier
Down
Converter
Tunable
Local
Oscillator
Filter
Demodu
lator
TV SET
Video
baseband
Low noise block
down converter
Channel Selector

16. COAXIAL CABLE: -
Coaxial cable connect LNBF to set top box.
A transmission cable consist of outer metal conductor
enclosing and insulated from a central conducting rod.
Impedance provided by the coaxial cable can be calculated
by the formula
Zo = (1/2Π)√μ/ε ln(D/d)
Where
μ = relative permeability of insulator
ε = dielectric constant
D = Outer diameter of coaxial cable
d = Inner diameter of coaxial cable

17. A set top box can demodulate
the received signal and can
convert these signal into audio
and video signal.
SET TOP BOX: -

18. SET TOP BOX BLOCK DIAGRAM: -

19. CONT….
TUNNER: -
It select particular channel range from 48 MHz to 840 MHz.
DEMODULATOR: -
Selected channel demodulated and fed to decoder.
DECODER: -
It is D to A converter which provide audio and video as signal
output.
MICROCONTROLLER: -
It control all the process performed by each block.

20. HOW DOES D.T.H DIFFERS FORM
CABLE T.V: -
• In D.T.H, the T.V channels are directly transmitted
from satellite to small dish antenna at subscriber
home.
• The broadcaster directly connected to the
subscriber, the middlemen like local cable
operator are not there in the picture, hence provide
better picture quality directly from satellite to user.

21. CONT….
The cable T.V were limited to the urban area, but
D.T.H followed cable T.V in urban as well as in
rural area.
D.T.H technology are more resistive to weather
conditions, it can work in any type of
environment.
Since less coaxial cable connection are used in
D.T.H technology, less distortion of the signal
tacks place, which ultimately provides better
signal and better picture quality

22. D.T.H PROVIDER’S IN INDIA: -
 DISH T.V
 TATASKY
 BIG T.V
 SUN DIRECT
 VIDEOCON d2h
 AIRTEL DIGITAL TV
 D.D. DIRECT

23. D.T.H SERVICE PROVIDER: -

24. LATEST IN DTH IN INDIA
Recording of TV programs
remotely using mobile
device.

25. CONCLUSION: -
o DTH has made the hopes of the people of rural
areas to come true.
o DTH service in India is in initial stage delivering only
TV broadcasting
o In near future, launch of DTH internet service is
expected in our country.
o It provide the wide thinking of rural people which
helps to develop the culture of society.

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