A Introduction To Satellite Television

A Introduction To orbiter TelevisionSatellite video recording first the consumer market in the early 1990s. distributees made for the average house were expensive and took up a lot of space in the garden. I n the first few years of satellite TV b bely the wealthiest, or more die-hard fans of television, would go to the trouble of buying and fit up a satellite discus antenna. Satellite television was to a fault a lot harder to get than cable or institutionalize TV.In the indue day you see satellite dishes on the rooftops of most homeowners in the UK and and so the rest of the western orb. The major satellite TV companies are get more and more people to buy their product with promises of films, sports and especially countersign from some the world. The advancement into broad(prenominal)-definition televisions and being able to get a heights definition satellite betoken has made it even more prominent.Satellite Television gives us many solutions to the riddles that come with spread out TV and, although non perfect itself, is now the main way to view television.In its basal form satellite television is a lot like broadcast television. They are both a wireless establishment for delivering television computer programing to a informants house. And they both use satellite post to pass on programing via a radio contract.Using powerful antennas broadcast stations disseminate radio waves to the area surrounding them. The viewers, however, pick up the preindication with a oft modester antenna. Broadcast television works ticket it that has one massive drawback, which is range. When a broadcast antenna shoots break a radio token it is shot out in a straight parameter. To scram these signals you have to be in the direct line of sight of the antenna. If you are not the signal may become distorted. exquisite obstacles such as trees or small buildings should not be a problem but bigger obstacles, such as planet earth, would come a probl em. If you glowted a broadcast signal over a perfectly flat surface you would be able to pick up a signal thousands of miles away from the source. However in the real world the curvature of the planet distorts and blocks the signal sent out from the satellite, to get a perfect signal you would have to be close to the antenna with no obstacles in in the midst of.The Satellite TV SolutionSatellite TV solves this problem by transmitting signal from satellites orbiting the Earth. Because these satellites are so high in the sky it means there are a lot more customers in range and line of sight. Satellite TV systems transmit and receive radio signals using specialized antennas called satellite dishes.Diagram of how Satellite TV works.When the satellites that broadcast these radio signals are sent up in to space they are all sent up in fixed orbit. This means that they all stay in one place in the sky relative to the Earth.Some factsEvery satellite is launched into space at 7000mphEach one reaches about 22,200 miles above the Earth.When the satellite is this high and mournful at such a speed it will revolve around the Earth once every 24 hours, keeping it in the equivalent position above the Earth giving constant signal to the viewer with uninterrupted signals.The Components of Satellite TVIn a DTH (direct to home) or DBS (direct broadcasting) satellite system there are five major components. These are the programming source, the broadcast cracker, the satellite, the satellite dish and the pass catcher.Programming source this is where the channels that get out the programmes are based. This is where the satellite TV canrs go to pay other companies (for sample MTV or Nickelodeon) for the right to broadcast there programmes through with(predicate) their satellites.Broadcast substance The broadcast internality is central part of the system. In the broadcast center the people who are providing the TV to the viwers at home receive signals from unlike progra mming sources and then beam a broadcast signal to satellites to geosynchronous orbit.Satellites The satellites in space receive the signal sent from the broadcast center and beam them back down to Earth.Dish The viewer then picks up this rebroadcasted signal and the satellite dish passes it onto the receiver in the house.Receiver all(prenominal) the receiver then has to is process the signal and pass it on to a mensuration TV.This is a very hot system to providing a good look signal to a large area. It has very picture demonstrate and sound quality with hundreds of channels and the service is ready to use in rural and urban areas and provides a lot of access to digital and high definition programming. However satellite is not without its drawbacks. It can be rather expensive to buy all the equipment at the outset (satellite dish and receiver etc) and if you want to access satellite television in multiple suite in your home be prepared for the extra cost. As good as this s atellite television can be subject to extreme weather conditions.Satellite TV signalsSatellites signals have a very pine way to travel before they appear on your TV screen. Because of this and because they ascertain very high-quality digital data it would be near impossible to transmit them without compression. Compression is defined, in this case, as removing all unnecessary or repeated information. later the signal is transmitted it is reconstructed.Satellite TV has to use a very unique type of video file compression rule-governedize by the Moving Pictures Experts Group or MPEG for short. This allows the provider to successfully transmit significantly more channels than without using this method of compression.MPEG normals exist to pull ahead interoperability among your computer, televisionand hand held video and audio devices. These MPEG standards areMPEG-1 this is the original standard. It is use for encode and decoding streaming video and audio files.MPEG-2 this standa rd compresses files which are used and transmitted for a high quality of video and is the standard for digital television.MPEG-4 the function of this standard is to compress high definition video onto a smaller scale so you can stream it to computers, mobile phones and PDAs.MPEG-21 This standard basically interprets digital content so that the media plays flawlessly no social function what machine it is, what language it is in or the user conditions. It is also referred as the Multimedia Framework.Most satellite TV providers used to use the MPEG-2 standard to compress their signals but changed to the MPEG-4 standard of compression. This is because MPEG-4 is more efficient at encode can provide a much greater bandwidth than MPEG-2. However MPEG-2 assuage remains the official standard for digital television. This is because it is more able to crush static images, like those you would see in such programmes like lambast shows or newscasts whereas MPEG-4 is better at analysing movi ng, dynamic images. MPEG-4 can do this through such things as spatial1and temporal2compression. This is how satellite TV manages to provide such a high quality picture of fast-moving objects on the screen, that are always moving, like in a football game.Satellite DishWhen the signal reaches the viewers house it is captured by the satellite dish. The satellite dish is made up of an aparabolic (bowl- organized) surface and a central feed horn. The signal passes through the horn and then the dish focuses the signal into a narrow beam.This receiving dish works in the exact opposite way to the vector as it cant transmit information, it can only receive it. The dish acts just like a concave mirror in that the shape of the dish reflects the signal inward onto a position point just like a concave mirror focuses light onto a particular point.The dishes feed horn feeds the signal on to the receiving equipment, and if there hasnt been any obstacles between the satellite and the dish there s hould be a perfect signal coming into the viewers receiver (unless the weather is bad). Before the dish sends the signal to the viewers receiver it amplifies and filters the signal using LNB, or low mental disturbance blockdown converter. After this the LNB passes the amplified, filtered signal to inside the house.sometimes, in some systems, the dish postulate to pick up a signal from two different satellites. Sometimes this may be possible but when it isnt it may compromise the quality of the signal because the dish cannot be aimed at both of the satellites at the equivalent time so either one or both of the signals would be distorted.Satellite ReceiverAt the end of the satellite TV system is the receiver. It has four important jobsIt takes the encrypted signal and de-scrambles itIt takes the digital MPEG-2 or MPEG-4 signal and changes them into an analogue signal so the standard television can recognizeIt also has to sort out the individualAs well as this it keeps the providers provide up to date with the payments the viewer owes the provider of the satellite television.ConclusionAfter closely studying satellite television and how it works it is clear to me that is much better and more practical then the older normal broadcast television. This is because of the greater range and line of sight that satellites have got rather than the regular antennas which are impeded by the curvature of the earth and even small obstacles. Although satellite television does have some drawbacks I would say it is in spades the way forward in television broadcasting and has already intimately taken over the market.