1. Audio video system Name:- LALWANI MOHIT JAIRAMDAS
Enrollment no.:
Department:- EC sem 5

2. TOPIC:- DTH(DIRECT TO HOME)
SATELLITE TV

3. CONTENT INTRODUCTION HISTORY OF DTH MAIN BOLCK OF DTH DTH NETWORK
SATELLITE TRANSMITTER
MINIDISH ANTENNA
SIGNAL RECEIVED BY MINIDISH
LNBF
SETTOP BOX
SETTOP BOX BLOCK DIAGRAM
DTH DIFFER FROM CABLES
ADVANTAGE
DISADVANTAGE

4. Introduction:- DTH means “DIRECT TO HOME”.
DTH is a receiver which is use to receive the satellite program via individual antena . The program is transmitted by transmitter.
WHY DTH IS FOUND?
The answer is “initially cables are required to transmit and receive the signal. In this process there are many losses with cables like noise affected ,signal distortion , high cost because of many cables are use.
DTH is wireless communication. Small losses because No large no. of cables are use, not very costly.
Today DTH is use everywhere in the TV transmitter & receiver ,mobile recharge, etc.

5. HISTORY OF DTH :-
The first person who invented the technology of DTH was “ARTHURE CLARLES CLARKE” British inventor In late 1946.
The DTH service was first proposed in India in 1996.But was not approve due to concern over national security.
Finally in 2000 the DTH service was allowed and “DOORDARSHAN” was 1st to provide DTH service to the consumers from 1st April, 2000.
After this the other service provider like ZEE and STAR started pushing hard for DTH service in India
Finally setup earth station whose cost was 2.15 millions , valid for 10 years in India.

6. MAIN BLOCKS OF DTH:- Broadcasting Center Satellite Encoder
Multiplexers
Modulators
DTH Receiver

7. DTH NETWORK:-

8. SATELLITE TRANSMITTER:-
Transmitted signal
Our home dish antenna

9. MINIDISH ANTENNA:-
It is parabolic reflector it receive the signal and fed to the LNBF.
LBNF=LOW NOISE BAND DOWN CONVERTER
Which work as receiver for the transmitted signal by satellite transmitter.

10. Signal received by mini dish:-
Signal is come to the parabolic reflector and focused at the center of parabolic reflector where LNB is present.

11. LNBF(LOW NOISE BLOCK DOWN CONVERTER):-
It collect the signal from mini dish.
It receive the signal from ku band and down converter to radio frequency signal.
It amplify and remove the distortion from received signal.

12. BLOCK DIAGRAM OF DTH SYSTEM:-

13. SETTOP BOX:-
The settop box can demodulate the signal and convert it into audio and video signal.

14. BLOCK DIAGRAM OF SETTOP BOX:-
TUNER:-
It select particular channel range from 48mhz to 840mhz.
DEMODULATOR:-
Selected channel demodulator and fed on decoder.
DECODER:-
It D to A convert which provide audio and video signal.
MICROCONTROLLER:-
It control all the process perform by the blocks.

15. HOW DOES DTH DIFFER FROM CABLE:-
In DTH TV signal is directly transmitted via satellite to small dish antenna at subscriber home.
the broadcaster directly connected to subscriber the local cable provider is not present.
The cable is limited for urban areas but DTH is also used in rural areas.
DTH can be work in any type of environment.

16. ADVANTAGES:-
As the DTH service is based on satellite and there is not requirement of wires signal like cable TV connection.
With DTH service anybody can get high quality digital signal on the television.
DTH is very useful in the remote locations where the poor quality signal of television.
DTH also give us best sound and clear picture quality.
The main benefit of DTH service, this work on single channel and subscriber do not require to buy new television with more channels. We can change channel through the set-top box of DTH service.
The main advantage of DTH service, due to high quality picture and sound, we cannot get much stain on our eyes and ears.

17. DISADVANTAGES:-
In heavy rain we cannot clear signal or no signal to view any channel. This is the major problem for the subscribers of DTH (Direct-To-Home) service.
Another major problem is that we cannot change our service provider. If any service provider give us service badly and then 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.

18. THE END
THANK YOU