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Por todos es sabido, que para garantizar el proceso y la calidad de una fusión (independientemente del tipo de fibra utilizada) resulta imprescindible tanto la calidad de la fusionadora, como aquellos conocimientos sobre el proceso que el técnico precise aportar para lograr un trabajo excelente. Por ello, y teniendo en cuenta que con el paso del tiempo las fusionadoras han mejorado sus funcionalidades y características para soportar todo tipo de inconvenientes aportados por la fibra, mediante la siguiente redacción resumiremos los correctos pasos para un buena fusión:

TVi Televisão Independente S.A. es un operador de televisión que cuenta con diversos canales en Portugal, tales como TVi24, TVi Internacional, TVi África, TVi Direct, TVi Eventos, TVi Reality, TVi Ficção, +TVi y el propio TVi.

Las dos cabeceras analógicas originales que equipaban su sede, han sido sustituidas por dos nuevos conjuntos de compuestos por módulos digitales. Los nuevos racks se han equipado con encóders para que sus correspondientes fuentes de señal se integren con de los contenidos de TVi. Los encoders T.0X generan 24 programas internos modulados en SD y dos programas en HD, con una calidad de señal excepcional

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In 1991, broadcasters and equipment manufacturers combined efforts to provide a European Digital Terrestrial Television platform. The European Launching Group (ELG) was created, which expansion to other public and private groups laid the ground for the DVB project.

For legal and technological complexity reasons, the first digital services were broadcasted through satellite and cable: the so-called DVB-S and DVB-C, which standards were published in 1994. Service deployment to the final user was possible thanks to the MPEG2 audio/video compression algorithm, which allowed the use of manageable bit rates (15 Mbps at the very beginning!) with a good quality of compressed video. It was only in 1997 that DVB-T, the standard for digital terrestrial television, was published, thus completing the current set of standards.

These standards allowed the deployment of broadcasting services beyond Europe. Nowadays all the countries in the world —except for the US, China, Japan and Brazil— use some DVB broadcasting standard.

The standards had to evolve to a second generation when the need for a better usage of the broadcasting spectrum arose. DVB-S2, DVB-C2 and DVB-T2 gradually appeared, which brought the channel capacity close to the so-called “Shannon limit” (which establishes the maximum channel capacity for a given bandwidth and signal-to-noise ratio). This means there will not be a third generation of broadcasting standards. However, DVB-S2 has evolved to DVB-S2X, which substantially improves capacity for both very high and very low signal-to-noise ratios.

Some of the DVB-S2 modes, especially DVB-S2X, are used for satellite data distribution, while DVB-C2 is used for data distribution over cable and optical fibre networks. Finally, DVB-T2, which has already been widely deployed in Europe and Asia, has allowed UHD diffusion.

DVB has revolutionised content broadcasting over the last two decades. This short summary of its evolution left multiple topics out: content treatment and delivery, Conditional Access, IPTV, new MPEG4 and HEVC coding standards, 3DTV, LTE, Virtual Reality, and many others. They will be addressed in next issues