DVB-T2 in relation to the DVB-x2 Family of Standards

DVB-T2 is a second-generation standard for terrestrial broadcasting aimed at broadcasting to fixed and portable receivers. DVB-T2-based HDTV services have started being broadcast in the UK and other countries are planning to start similar services in the near future. This paper concentrates on the key features of the DVB-T2 system, illustrating how these build on the innovations introduced in the second-generation satellite transmission standard DVB-S2. A second-generation transmission standard, DVB-C2 has also been defined for cable systems and this system is also briefly described. These three new standards form a distinct ‘family of standards’ with many features in common. History By the mid 1990’s, the DVB organisation had defined three principal standards, DVB-S, DVB-T and DVB-C for distribution of TV over satellite, terrestrial and cable channels. Ten years later, the DVB organisation defined its first ‘second-generation’ DVB-S2 standard [1], in order to take advantage of the greatly improved capabilities of decoder-chip VLSI capabilities. This new satellite standard provided for a 30% increase in transmission capacity compared with DVB-S and was intended primarily for HDTV broadcasting. In DVB-S2, the forward error correction is based on advanced Low Density Parity Check Codes (LDPC) concatenated with BCH codes and these take the available performance close to the Shannon limit. In 2006, it was widely recognised within DVB that, building on the improvements in DVB-S2, similar improvements might be achievable for terrestrial broadcasting and that such improvements could help the terrestrial platform in Europe migrate towards HDTV. Consequently, DVB launched a technical group to define the next-generation, DVB-T2 standard which was eventually published in June 2008 [2][3]. At the same time, the UK was busy planning for digital switch-over (DSO) which was to be completed by mid 2012. It was decided that, as part of the regional roll-out of DSO, one of the public service multiplexes would be converted to DVB-T2 in order to carry terrestrial HD services. This decision was taken on the understanding that a DVB-T2-based multiplex would be able to deliver at least 30% more capacity than a conventional DVB-T multiplex for the same coverage planning parameters. Additionally, with a timetable determined by the UK regional DSO schedule, the launch date for these new HD services was set to be December 2009. These UK decisions helped to generate industry interest in the new standard and the short timescales helped to drive the standardisation process forward. More than 40 companies have actively