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Digital TV

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After the choice of the Japanese model, now it?s the time of innovations

MIGUEL BOYAYANAfter years of negotiations, the Japanese digital television transmission system overcame the European and American standards and will be adopted in Brazil. The Presidential Decree Nº 5.820 decided upon the Japanese Integrated System Digital Broadcasting (ISDB) and provides the directives for the implantation of the Brazilian Terrestrial System of Digital TV (SBTVD-T in the Portuguese Acronym). In the beginning, the digital signal will only be captured by those who acquire a small device, called an access terminal. But later the TVs prepared with the new technology will be available, as well as cellular phones or computers with special chips for the reception of the TV signal. In tests with the three standards carried out in São Paulo since 1998 by the Digital TV Laboratory of the Presbyterian Mackenzie University, the Japanese system showed itself to be the most robust for the Brazilian television service, in the majority of cases captured by antennae, as well as being less receptive to interference and apt in mobility (see Pesquisa FAPESP Nº 120).

The question now, in a period of almost one and a half years, when the first Brazilian digital TV signals should be on the air, concerns the studies for the incorporation of part of the technologies developed by around 1,200 Brazilian researchers at 75 research institutions and companies and of almost R$ 40 million in investments. The modulation system is Japanese, but other important subsystems for the working of digital TV will be linked onto the SBTVD-T. Starting from this month of August, researchers and technicians of both countries are beginning to meet together and decide on the new devices for Brazilian TV. “This will be a hybrid system with innovations”, affirmed André Barbosa Filho, a member of the SBTVD-T development committee and an advisor to the minister of the Executive Office Ministry, Dilma Rousseff. Among the innovations should be middleware, the system that codifies and de-codifies the flux of bits and identifies that which is sound, video and interactive data. Various groups have developed middleware. Among them are researchers at the Catholic Pontifical University of Rio de Janeiro (PUC-Rio), the Federal University of Paraíba (UFPB) and the State University of Campinas (Unicamp).

The system for the compression of video should be one of the most advanced in the world with the adoption of the MPEG-4 system, Moving Picture Experts Group, invented by a group of world specialists who decided upon the standardization of communication media. This version is more advanced than that of the MPEG-2 used by the Japanese and by the majority of European TVs. Research with the MPEG-4 was done by the University of the Bells River Valley (Unisinos), of São  Leopoldo, in Rio Grande do Sul State. There will be space as well for software that groups together the very characteristics of Brazilian culture and facilitates digital inclusion.

“We’re also pushing for a special program for terminal access. We don’t want only an improved video signal, we want applications that guarantee even to download information transmitted by the television companies”, explains Barbosa Filho. This will be important, principally on channels and educational programs that must be transmitted on the four public channels, which will be created with the SBTVD-T. “We’re beginning an effort to integrate knowledge generated in other universities. We’re consolidating and harmonizing the development of the terminal”, says Marcelo Knörich Zuffo, a professor at the Integrated Systems Laboratory (LSI) of the Polytechnic School of the University of Sao Paulo (Poli-USP), the coordinator of the group that developed the terminal. Within these studies there was also participation from electro-electronic companies and the TV broadcasting companies. “We need to work in conjunction, without diminishing or isolating the role of the universities in our advantage, not only of economic pressure, of quickly placing the terminals on the market”, says Zuffo.