Digital TV, often abbreviated as DTV, is the broadcasting of television via digital signals – the pictures and sound are converted into digital signals and compressed before being broadcast, while the analog signals cannot be compressed.
What is a digital TV transition?
Digital TV transition, also known as digital TV switchover in some countries, is the process of rendering the older, analog television broadcasting obsolete and replacing it with digital TV broadcasting. The process was completed in the United States by June 12th 2009 after several delays, and other industrial countries have passed legislation taking steps in the same direction.
In Germany, the digital TV transition began in the Berlin area and the terrestrial digital TV transition was completed in 2009 in the rest of the country, while the existing analog cable and analog satellite broadcasting will be switched off in 2012. In the United Kingdom the process has started in 2008 and should be completed by the end of 2010, while all of the Scandinavian countries have already successfully completed the transition from analog to digital TV.
Digital TV vs. analog TV
Digital TV vs. analog TV: what are the advantages of digital TV broadcasting?
As already mentioned, the main advantage of the digital TV transmitting is that the television signal can be compressed, much like the files on a computer's hard drive. This enables the transmitting of as much as five times more information, using the same amount of bandwidth and this automatically results in the ability to broadcast more channels, without having to expand the frequency bandwidth.
The digital TV also offers new features like interactivity, on-screen listings, and wide screen pictures, and new services and packages like telephony, high-speed broadband Internet, and premium channels; subtitling and audio descriptions are also possible and likely to benefit older and disabled viewers.
The video signal in digital TV is encoded by using the MPEG-2 standard, which although has its disadvantages, still provides much better image quality than the standard NTSC analog image. Some digital TV programs are available with Dolby Digital AC-3 sound, which is the same audio encoding system that has been used in movie theaters and offers superb quality sound.
Another great characteristic of the digital TV broadcasting is that it keeps the quality of its signal – the analog TV signal weakens as the signal is transmitted farther away from the broadcasting station and this results in poorer picture and sound quality in the remote areas. The digital signal retains its quality, no matter how far the receiver is from the broadcasting station, as long as he is capable of receiving that signal.
Are there any drawbacks to switching to digital TV?
Although the digital TV is seen as a step in the right direction, it has its disadvantages with the two main concerns being the cost of the digital TV transition and the fact that many households had to either buy new, digitally enabled TV sets, or purchase analog-to-digital converters for each existing TV set in order to be able to watch digital TV.
Another concern was raised by the fact that the transition dramatically increased the disposal of old TV sets and their recycling is not always easy and is very costly. You don't even need to buy a digital tv antenna.
Overall, the digital TV advantages far outweigh its disadvantages and in the near future we are likely to see even more new and exciting features and services that will dramatically change the way we are informed and entertained!
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