Beginner’s Guide to how the Satellite TV Works and Its Scope

• Programming sources are simply the channels that provide programming for broadcast. The provider doesn’t create original programming itself; it pays other companies (HBO, for example, or ESPN SKY) for the right to broadcast their content via satellite. In this way, the provider is kind of like a broker between you and the actual programming sources.
• The broadcast center is the central hub of the system. At the broadcast center, the TV provider receives signals from various programming sources and beams a broadcast signal to satellites in geosynchronous orbit.
• The satellites receive the signals from the broadcast station and rebroadcast them to Earth.
• The viewer’s dish picks up the signal from the satellite (or multiple satellites in the same part of the sky) and passes it on to the receiver in the viewer’s house.
• The receiver processes the signal and passes it on to a standard TV.

• Cable advantages: Advancements in digital cable provide improved audio and picture quality with additional channels at a lower cost than satellite. You can also access cable channels from multiple rooms in your house fairly easily.
• Cable disadvantages: Cable has limited access to rural areas, and you should prepare for increased service costs as your provider updates its equipment. Your service costs are also subject to local taxes.
• Satellite advantages: Satellite offers movie-quality audio and picture display with hundreds of channels. This service is readily available in rural and urban areas and provides access to more digital and high definition programming.
• Satellite disadvantages: It is expensive to purchase all the equipment at the outset (and you can’t typically rent it). If you want to access satellite TV in multiple rooms, be prepared for extra fees. Also, satellite TV is subject to weather-related malfunctions.

Satellite TV Scope: Signals & their Compression

As you should expect, is a very long process involved before satellite tv channels appear on your TV screen in the form of your favorite TV show. The reason is that satellite signals contain such high-quality digital data, it would be impossible to transmit them without compression. Compression simply means that unnecessary or repetitive information is removed from the signal before it is transmitted. The signal is reconstructed after transmission.

Standards of Compression

Satellite TV uses a special type of video file compression standardized by the Moving Picture Experts Group (MPEG). With MPEG compression, the provider is able to transmit significantly more channels. Also, there are currently five of these MPEG standards, each serving a different purpose. DirecTV and DISH Network, the two major satellite TV providers once used MPEG-2, which is still used to store movies on DVDs and for digital cable television (DTV). With MPEG-2, the TV provider can reduce the 270-Mbps stream to about 5 or 10 Mbps (depending on the type of programming).

Now, DirecTV and DISH Network use MPEG-4 compression. Because MPEG-4 was originally designed for streaming video in small-screen media like computers, it can encode more efficiently and provide greater bandwidth than MPEG-2.

Meanwhile, MPEG-2 remains the official standard for digital TV compression. MPEG-4 can produce a better picture of dynamic images through the use of spatial (space) and temporal (time) compression. This is why satellite TV using MPEG-4 compression provides a high definition of quickly-moving objects that constantly change place and direction on the screen, like in a basketball or soccer game.

Satellite TV Encoding and Encryption?

This is the most technical and most frustrating aspect. Hackers have a tough time hacking encrypted channels while we consumers wish every receivable channel is free to air. At the broadcast center, the high-quality digital stream of the video goes through a MPEG encoder, which converts the programming to MPEG-4 video of the correct size and format for the satellite receiver in your house.

Noteworthy, encoding works in conjunction with compression to analyze each video frame and eliminate redundant or irrelevant data and extrapolate information from other frames. Each frame can be encoded in one of three ways:

How to encode Satellite frames

This process occasionally produces artifacts – glitches in the video image. One artifact is macroblocking, in which the fluid picture temporarily dissolves into blocks. Macroblocking is often mistakenly called pixelating, a technically incorrect term that has been accepted as slang for this annoying artifact.

Graphic artists and video editors use “pixelating” more accurately to refer to the distortion of an image. There really are pixels on your TV screen, but they’re too small for your human eye to perceive them individually. Pixels are tiny squares of video data that make up the image you see.

The rate of compression depends on the nature of the programming. for instance, If the encoder is converting a newscast, it can use a lot more predicted frames because most of the scene stays the same from one frame to the next. In more fast-paced programming, things change very quickly from one frame to the next, so the encoder has to create more intraframes. As a result, a newscast generally compresses to a smaller size than something like a car race.

Satellite TV Scope: Encryption and Transmission Process

After the video is compressed, the provider encrypts it to keep people from accessing it for free. Encryption scrambles the digital data in such a way that it can only be decrypted (converted back into usable data) if the receiver has the correct decryption algorithm and security keys.

After compressing and encrypting the signal, the broadcast centre beams it directly to one of its satellites. The satellite picks up the signal with an onboard dish, amplifies the signal and uses another dish to beam the signal back to Earth.It is when the signal gets to the Earth that viewers can pick it up. next, we’ll see what happens when the signal reaches a viewer’s house.

How Satellite Channels are Received by Users at Home

• It de-scrambles the encrypted signal. In order to unlock the signal, the receiver needs the proper decoder chip for that programming package. The provider can communicate with the chip, via the satellite signal, in other to make the necessary adjustments to its decoding programs. Furthermore, the provider may occasionally send signals that disrupt illegal de-scramblers as an electronic countermeasure (ECM) against illegal users. Note; Satellite TV can also be viewed as Free to Air(FTA)
• Technically, a decoder takes the digital MPEG-2 or MPEG-4 or HD signal and converts it into a format that a standard television can recognize.
• Furthermore, a receiver extracts the individual channels from the larger satellite signal. When you change the channel on the receiver, it sends just the signal for that channel to your TV. Since the receiver spits out only one channel at a time, you can’t tape one program and watch another. Also, you can’t watch two different programs on two TVs hooked up to the same receiver. In order to do these things, which are standard on conventional cable, you need to buy an additional receiver or get some other 3rd party components read more here.
• Finally, a receiver keeps track of pay-per-view programs