 Hello everyone, I am Mr. Praveen Yalapa Kumbar. Welcome to the session. Today we want to see DTH. The learning outcome of this topic is, at the end of the session, students will be able to explain the concept of DTH in multimedia communication techniques. The contents of these topics are introduction, history, components of DTH, advantages and disadvantages of the DTH and applications. The contents of these topics are introduction, history, components of DTH, advantage and applications. Introduction. DTH stands for Direct-to-Home Service. The Direct-to-Home Service is a digital satellite service. Here we use digital satellite service. It is advantages over the analog services. The first advantage of digital satellite service over the analog service is that the noise generation in the digital is very low as compared to the analog service. DTH provides television service direct to the subscriber. Here no intermediate services to be provided. It is directly service provided to the subscriber and it is advantages. Therefore, DTH can be defined as the reception of satellite programmers with a personal dish at individual home. Now, we want to see the history of the DTH. The DTH was firstly invented by Sir Arthurie Clarellis Clark. He is a British inventor in the late 1946. The DTH services was first proposed in India in 1996, but due to the certain national security reasons it will not be approved in 1996. But finally, in 2000, DTH service was allowed and after that one, Durudharshan was the first service to provide to the consumers. Now, we want to see the components of the DTH. The components of the DTH are first, this one satellite, second, broadcasting centers, third, multiplexers, fourth, modulators and fifth, encoders. Now, we want to see this one by one the components of the DTH. Now, this figure 2 shows the block diagram of the DTH. Now, detailed block diagram we want to understood by one by one. Now, see first, here television channel or station where the programs will be the recorded after that one it will be the uploaded through the satellite and after that one it will be the downloaded towards this DTH provided companies and here we encryption technique is used as MPG-2. After that one when we receive the signals into the DTH, DTH will provide the signal to the consumer by with the help of first of all it will upload the program through the satellite and it will be downloaded into the DTH receiver which is located on the home or the office. After that one when we receive the signal it will go to the set of box and after that one it will go to the different procedure that is modulation and demodulation techniques that will receive on this TV channels and consumer will see that all these programs. Now, we want to see one by one that is out of that one first one is satellites. Before going to these satellites everyone pause the video and recall what is meant by the satellite. Okay, now satellite means it will be the transmit as well as receive the signals from the Earth station or to the Earth station. Here in the satellites mainly for the DTH we use a geostationary satellite. Therefore a geostationary satellite plays an important role in the DTH system. Each satellite is launched into the space at about 7,000 mile per hour that is if you convert into the kilometer per hour that is 11,000 kilometer per hour reaching approximately 22,200 miles that is 35,700 kilometer above the Earth. It is the location of the geostationary satellite which is used for the DTH system. Therefore in India DD Direct and this TV transmission service are from NSS-6 satellites. Now when we use NSS-6 satellites then their specification are also important for this NSS-6 satellites. Now everyone observes this specification of NSS-6 satellites and after the observation of this NSS-6 satellites here we use number of KU band transponders is 60 and here modulation type we use as a QPSK and one more important thing for this one uplink and downlink frequency that uplink frequency is 30.75 to 14.5 gigahertz and the downlink frequency range is 10.95 to 12.75 in that one we use different frequency band. Now we want to see broadcast center. The broadcast center is the central hub of the system. In the broadcast center here what will happen here we can take the programs and transmit the programs. Here at the broadcast center the television provider receive the signals from the various programming source and broadcast signal to satellites in geostationary orbit. The satellite receive the signals from the broadcast station and re-broadcast them to the ground. After the re-broadcast to the ground the DTH will receive their signal and to provide with the help of different operations we want to see on the TV channel. Next multiplexer. A multiplexer is a device which transmits the information of many channels into one channel and transmit it to the geostationary satellite. After that geostationary satellite it will again transmit towards the DTH antenna. The multiplexer is a built in the broadcasting center. It sends the signal channel to the modulator. Again now we want to see the next one is modulator. Modulation is a process in which the information signal is imposed on a carrier signal which is of a high strength. Here very high strength signals we require for transmission of this information. The modulator modulates the signal and sends to the encoder. Now we want to see what is the means of encoder. The encoder encodes the signals to transmit the signals. The satellite sends the signals to the DTH antenna. The antenna transmits the signals to the set-up box. After that set-up box it will be given to the TV channels with the help of different modulation and demodulation techniques that we will see on the TV. The other components of the DTH are first DTH antenna, second LNB and third one is set-up box. Now we want to see one by one that is first DTH antenna. Here antenna is used most of the important part because transmitter as well as receiver part is done in this antenna. Here antenna the reflector surface material must be constructed out of the metal in order to reflect the incoming microwave signals. Here for transmission as well as the receiver we use microwave signals. Some antenna reflectors appear to be manufactured out of plastic or fiber glass. Here in the antenna we use one of the reflector that will reflect whenever all the signals when I will get on this antenna that will be reflect to the LNB and we get the signals. The solid one piece metal antenna is most of the always the dish because the no assembly errors and reflector normally will maintain its precise shape over the lifetime of the system. Therefore we use here solid one piece metal antenna. Here antenna specifications are provided in this table and here are the different parameters and their respective values are provided for this standard DTH system. Now we want to see LNB. LNB means low noise block down converter. It is one of the most important part in the DTH system. It is available over the reflector part. Now the incoming satellite signals propagates down the wave guard of the feed horn. A tiny resonant probe is located on the LNB whenever this resonant probe is used because maximum energy we can utilize here due to this maximum energy utilization the errors will be less and noise will be the less. Therefore the internal noise contribution of the LNB is amplified after the amplification of this noise whenever we internal noise will be the amplified then noise will be the removed easily. Therefore the internal noise contribution of the LNB is amplified along with the incoming signal and passed on the succeeding amplifier stage and after that succeeding amplifier stages the noise will be removed. Now this table provides the LNB specifications. These are the different parameters and the respective values for this LNB specifications. Now set up box. Set up box accepts the entire down converted band. It separates out the individual transponder frequency. Signals are first converted to fixed intermeasure frequency and then it transmits to the QPSK demodulated. Again after that one the bit stream is processed and to detect and correct the errors. Again we here we use a digital demultiplexer. In the digital demultiplexer first it will extracts the bits for wanted channel. It sends them to the MPG decoder. Finally generates the analog audio and video signals with DI converted to the drive TV set. The advantages first cost effective communication information and entertainment to all. Second small size terminals can provide up to 4,000 TV channels and 2,000 radio channels. Detailed service bypasses mediators and thus content provider comes with customers directly. The applications first to view pay and free-to-air TV channels of various details platform on your home TV. Durdarshan free-to-air service providing 40 TV channels with no subscription fees. One can scan the entire globe with motorized dish using a CI setup box with the CAM modules. The references for these topics are thank you.