Concept in Definition ABC

Television has evolved a lot in recent years, and the key to that evolution It is found in DTT, acronym for Digital Terrestrial Television.

For most of us, what we achieve with introduction of this technology were more channels and new content, but in reality it implies much more (some of the things that it allows, underutilized).

DTT is the digitization of the audio and video signal broadcast through the network that formerly covered analog television.

In other words, where television "of a lifetime" used to pass, now these frequencies of the radioelectric space are used to pass digital information.

Although it has received some criticism, the digitization of television to make way for DTT provides a series of advantages that we will see below.

The first advantage of DTT is that through the radioelectric space through which a single television channel used to pass, now several can pass.

By having the information in Format digital, we can apply a algorithm

compression, for both video and audio (there are several available), without loss of quality or with minimal loss.

It multiplies - in theory; then depends on the decisions taken by each government or regulatory body that materialize in broadcast licenses - the number of TV channels available. The question of the quality of programming (that is, what are they used for) is another, which depends on the operators.

Regarding the quality, and although some claim that it is inferior (something that can be seen in the pixelation of some elements of the image), by having the signal digitized it is possible to apply algorithms for detection and correction of mistakes.

A frequency that previously supported a single channel and now supports multiple channels is called a multiplex.

The multiple, as they have been released, have been licensed by governments and entities administrators or regulators of the radioelectric space for use by the different channels of DTT.

Digital terrestrial television must also coexist with the frequencies used by other services, such as mobile telephony. This generates, in turn, a conflict, since all the parts demand more frequencies to be able to enjoy a greater bandwidth.

This brings us to the second advantage, and that is that the interferences that previously affected the analog television and that were explicitly shown in the image, can now be corrected to certain point.

This improves the image at specific moments, such as when there is some transient interference due to environmental conditions, signal reflections, or scattering. Energy.

Despite this, the introduction of DTT has also meant that some people in specific areas have problems receiving transmissions.

DTT allows the addition to the audio and video signal of a series of services that provide a certain interactivity to users.

For example, some data can be encoded for each program, such as its name, a synopsis, and even the names of the actors who participate.

It is also possible to enjoy a programming guide of the different channels, which allows us to know not only what what they are doing at that specific moment, but also what they are going to do on each channel in the following hours.

Payment platforms also have their place in DTT.

Since the audio and video information is digital, it can be encoded at the source so that a decoder is required at the destination to view it.

The adoption of DTT, which is gradually taking place around the world, has brought with it the so-called "analog blackout"

This consists of television and radio channels that until now broadcast exclusively through analog channels, now go on to broadcast exclusively through DTT and digitally.

Photos: Fotolia - Oleg / Kentoh

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