Imprimir Republish


Turbocharged TV

Researchers from 75 institutions present alternatives for the Brazilian Digital TV System

MIGUEL BOYAYANTV is going to get more sophisticated. It is going to win a digital transmission system that is in a process of formatting in Brazil and should go into Brazilian homes in the next few months. Digital TV is arriving with promises of an image with a better quality, interactivity, and a greater possibility for the dissemination of knowledge. To format the Brazilian Digital TV System (SBTVD in the Portuguese acronym ) within the country’s cultural, social and technological specific characteristics, over the last three years one of the most remarkable technological research networks was set up, perhaps only surpassed by the network of the genome projects.

In 2004 and 2005, 1,200 Brazilian researchers were brought together, representing 75 institutions, the majority of them universities, as well as research institutions and companies, which proposed to the Ministry of Communications (Minicom) a series of technical alternatives for implanting the system, from the choice of hardware and software and analysis of foreign standards to proposals for broadcasting educational content and operational and commercial applications.

This February, the federal government should announce the main guidelines for the SBTVD and which will be the subsystems adopted in relation to one of the three digital TV standards existing in the world: the American Advanced Television Systems Committee (ATSC), adopted by the United States, Canada, Mexico and South Korea; the European Digital Video Broadcasting (DVB), used in several countries of this continent and in Australia, Singapore and Taiwan; and the Japanese Integrated System Digital Broadcasting (ISDB), used only in Japan.

It is expected that the decision on the Brazilian system will take into account the reports with recommendations from the 20 research groups that, besides analyzing and testing the other standards, developed innovative solutions for the future Brazilian digital TV. Called consortiums, these groups received finance from the Financier of Studies and Projects (Finep) with funds from the Fund for Technological Development of Telecommunications (Funttel). “The total was R$ 38.7 million, passed on to Finep by Minicom”, says André de Castro Pereira Nunes, the coordinator of Finep’s public invitation on digital TV.

The groups sent the reports with the results at the end of December to the Research and Development in Telecommunications Center Foundation (CPqD), which coordinated the researches for Minicom. The decisions, which should not take into account all the proposals, because some groups offered different alternatives for certain technical aspects of digital TV, will be defined not only by Minicom, but also by the Ministry of Science and Technology, the Chief of Staff of the Presidency, and the Ministries of Industry and Commerce, Culture, Education, Planning, Foreign Relations and Finance, which make up the Development Committee, for the final approval of the President of the Republic.

The analysis for the decision takes into account a series of factors for the new television to be suitable for the Brazilian scenario, where about 90% of the population watches TV by the free-to-air system, free of charge and picked up in the air. The main proposal for digital TV is in the 1st paragraph of the first article of the presidential decree that instituted the SBTVD, on November 26, 2003: “To promote the social inclusion, the cultural diversity of the country and the national language by means of access to digital technology, with a view to the democratization of information”.

The intention is to endow this new media with resources that anybody can access, via remote control, besides the normal programming of the broadcasting stations, even making it possible to access the Internet via the TV screen. In Brazil, there are about 60 million TV sets in over 46 million domiciles, of which 90% tune in only to free-to-air TV, via electromagnetic waves. The paid TVs, using cable or mini-dishes, are in only 3 million homes. “The decree makes it clear that digital inclusion will have to be the cheapest possible, because it cannot be exclusive to a few that can pay”, says journalist Beth Carmona, the current president of TVE , who for six years ran TV Cultura, in São Paulo.

“Digital TV with interactivity is a modification of human attitude”, says André Barbosa Filho, a former professor of the Communication and Arts School of the University of São Paulo, one of the organizers of the book Digital Media and the current special advisor for the area of public policies and communication to the Chief of Staff of the Presidency, Minister Dilma Rousseff. “Before, he was a passive TV viewer, and now he will start participating and choosing information on the TV screen.” Another scholar of communication, Professor Muniz Sodré, from the Communication School of the Federal University of Rio de Janeiro (UFRJ) and current president of the National Library, says that the new technology is a conquest. “But, in cultural terms, I am skeptical as to the production of new directions and dissemination of ethical values. One runs the risk of the convergence with the Internet, not reaching everybody, or being restricted to that which the producers – that is to say, the broadcasting stations – put at the disposal of the TV viewers”, he says.

Social inclusion
For Professor Carlos Montez, from the Automation and Systems Department of the Federal University of Santa Catarina (UFSC), the new TV “is an opportunity for taking knowledge to more remote places, where people do not have access to the Internet, for example”. Together with journalist and UFSC professor Valdecir Becker, he is the author of the book Interactive Digital TV: concepts, challenges and prospects for Brazil. “Digital inclusion helps the individual to attain social inclusion”, says Montez, who took part in a consortium, coordinated by Jorge Campagnolo, also from UFSC, that studied and proposed standards for usability, which is the way how interactivity should be produced for TV and how people are going to adapt better to it.

“It is a technological change that has a great social, cultural and industrial impact, which makes the decision very difficult, because it involves major interests. It is calculated that digital TV is Brazil is going to have a turnover of about US$ 20 billion, between the electrical and electronic industry, broadcasting station equipment and production of content”, says Barbosa Filho. “It also changes the way of producing the content, the scenery , the lighting and even the advertising, which is going to offer new ways of purchasing via the TV screen”, Beth Carmona explains. Just as in a TV program or in specific channels there may be content about health, for example, digital TV opens up the possibility of a direct purchase of something that is being shown on the screen.

Making a decision is, therefore, extremely complex. To get a basis for a definition for the technical area, the government formed the consortiums that presented innovative proposals for the various subsystems of digital TV. Amongst those that will be closer to the consumer, or viewer, there is the access terminal, or set-top box, an electronic box similar to the cable TV terminals to be connected to present-day TV sets with analog technology, making it possible to capture the digital signals that the broadcasting stations are going to emit. Later on, this piece of equipment will be incorporated naturally into the new TV sets. The forecast is that for 15 years the analog system will continue to be transmitted until the total of TV sets is changed, or all the analog TVs have a digital terminal. The initial amount forecast for this terminal is up to R$ 300.00, with an annual amortization of 20%.

Even with this terminal, the users are not going to have a high definition television (HDTV). This is only going to happen on purchasing a new TV that has a definition of 1,080 lines on the screen. The present-day ones have a resolution of 520 lines. Some plasma or liquid crystal televisions, already present in the stores, have digital resolution, though they will have to have a terminal connected to them. In present-day TVs, the image with the terminal should improve considerably, that is to say, there will be no snow or ghosts.

Another technical possibility for digital TV is multiprogramming, in which the same broadcasting station in each locality can have, within the same 6 megahertz (MHz) transmission band, various channels, each of them with a programming, or, even, according to future regulations, set aside these channels for other content producers – today, a broadcasting station can only transmit by one channel. This kind of option is well characterized in the European system.

In this case, transmission would not be in HDTV, but rather in the Standard (SDTV) mode in all the channels, in a way that is comparable to the quality of DVD. A difficulty there could by not taking advantage of a television with HDTV technology. Another option would be to adopt a compression system for transmission called Moving Picture Expert Group 4 (MPEG4), an advance on MPEG 2, a system much used on the Internet, which may provide for one HDTV channel and one or more in SDTV. There is also the improved option offered by Enhanced Definition Television (EDTV), which transmits in 720 lines, to DVD standard, also capable of accommodating multichannels.

General information
All the accesses to the channels and the interactivity with the TV viewer will be commanded by the terminal and a remote control. These will open up access, for example, to details of a given program, to voting, or to information about the economy, recipes, sports etc. It will also be possible with the terminal to access public information, like balances of the severance indemnity fund and  the Federal Pension System (INSS), or even getting information about diseases or booking appointments with the Public Health System (SUS), as foreseen by another consortium housed in UFSC and coordinated by Aldo Wangenheim.

“Our researches reached the point of endowing this terminal with Internet Protocol (IP) addressing, which can be used for mailbox addressing via e-mail and, later on, access to the Internet”, says Marcelo Knörich Zuffo, a professor from the Integrable Systems Laboratory from the Polytechnic School of the University of São Paulo (Poli-USP), the coordinator of the access terminal consortium. They even developed a standard of digital authentication that is going to prevent, for example, future contaminations with viruses in the system.

The terminal is accordingly the bridge for the so-called digital inclusion that the new TV is going to bring about for those who do not have a computer. “The group brought together 65 researchers, between professors, pupils and contracted engineers”, Zuffo says. Also taking part in this consortium were researchers from USP in São Carlos, the State University of Campinas (Unicamp), the Federal University of Paraíba (UFPB) and the Mackenzie Presbyterian University, of São Paulo, besides supporting companies like Brazil’s Waba, with software, Intel and Xilinx, with semicondutors, and Samsung and Itautec-Philco, with electronic products, the latter recently acquired by Gradiente.

The group’s ideal conception is to have a terminal that can incorporate various functions and in various models, from the most simple to the most sophisticated. “We are working on a multidefinition platform. That means that it will in future be possible to use it in situations of mobility, that is to say, to capture with a cell phone the signals of a digital TV directly from the TV broadcasting station”, Zuffo explains. This means that the system may be used in hand-held computers, TVs in automobiles etc. “It will even be possible to adapt applications (software) specific for navigability (maps) in a city, information about traffic, security, health, and much more.” In these cases, the standard is not HDTV, nor SDTV, but rather Low Definition Television (LDTV).

The access terminal should result in eight patents and the registration of some software that should shortly be filed and registered in Brazil and abroad. Several prototypes were built, with their respective electronic circuits designed and assembled, as well as having incorporated all the software need for them to work. “Within the cycle for developing a product, if our terminal is accepted, the next stage will be the adjustments that the manufacturers have to make to adapt it to the format of a commercial production”, says Zuffo.

The big decision that will be made in Brasilia is the choice of one of the three existing standards for digital TV – the American, the European and the Japanese. There may also be an option for improving one of them with what has been developed in the Brazilian research. This prospect has dominated the discussion about this new media since 1998, when the TV broadcasting stations decided to investigate the subject. “In 1998, we were invited by the Brazilian Society of Television and Telecommunications Engineering (SET) and by the Brazilian Association of Radio and Television Stations (Abert) to carry out an evaluation of the three digital TV standards”, says Professor Gunnar Bedicks Júnior, the coordinator of the Digital TV Laboratory of Mackenzie University. ‘We set up the laboratory with financial support from NEC via tax incentives under the Law on Information Technology”, says Bedicks. In the group, there is a professor from the same university, Francisco Sukys, one of the creators of the Pal-M system, the color TV standard in Brazil developed at the beginning of the 1970s.

Equipment and visits
The Mackenzie University  carried out the tests with the support of the National Telecommunications Agency (Anatel), which indicated the CPqD as a technical evaluator. “We purchased the equipment from the Americans and from the Europeans, and a van with devices and a retractable antenna, capable of reaching a height of 12 meters for doing field tests, initially in several districts of the city of São Paulo”, says Professor Cristiano Akamime, from the same laboratory. The Americans and the Europeans had already inaugurated their digital TV systems, and the Japanese were only to do this in 2003, although the equipment for the tests had arrived here in 2000. The researchers created procedures for tests in the three standards. “We received visits from the representatives of the three systems, who approved our procedures”, Bedicks says.

In 1999 and 2000, the researchers did tests with the three systems using the transmitting antenna of TV Cultura, in São Paulo, which coupled the digital signal via channel 34 in Ultra High Frequency (UHF). “We didn’t compare standards, what we did was to test the systems within the needs of our country. In 56% of the television sets, the quality of the image is not good, because several factors interfere with the signal, such as buildings, noises, transformers, the topography of the cities with many natural elevations, like hills.”

In São Paulo, some houses that are 4 kilometers from the antenna installed in the in the Sumaré district do not catch the analog signal of the TV with quality. These are the famous ghosts that digital TV is going to eliminate for once and for all. “In this system, either it catches well, or the screen stays dark”, says Akamime. This is how the researchers looked for the most robust system, which, besides having a strong signal, did not suffer the influence of electrical equipment like blenders, hair dryers etc.

“Right at the start we discarded the American standard, the ATSC, because the transmission was simply not reaching a large part of the television sets in some districts”, says Bedicks. It wasn’t made for free-to-air TV. In the United States, of the 110 million residences, 80 million are connected by cable, another 23 million capture the signal direct from the satellite, and only 5 million use the free-to-air TV signal. There, analog transmissions are forecast to end in 2009. In Brazil, the opposite occurs.

Only 4 million residences are connected to a subscriber service, out of a total of 45 million households. Without reliable statistics of how many capture the signals via unpaid parabolic dish antennas, it is estimated that about 90% of Brazilian television sets receive a free-to-air TV signal, either by means those outside antennas that are on the rooftops, or by indoor antennas. So free-to-air digital TV in Brazil has an important participation for all the layers of the population to have access to free transmission, and, as a consequence, to information, education, culture and entertainment.

The analysis of the European digital standard also showed that little attention was paid to free-to-air TV, although Italy and Spain have a significant portion in this segment. For this reason, this system proved to be well adapted to aerial transmission, but not inert to electrical and electronic interferences common in Brazil. “You just have to switch on a blender for it to interfere with the TV”, says Bedicks. “In Europe, they have earthing by a grounding wire with shielded three-pin plugs, which prevents interference, and not two-pin as in Brazil”, says Akamine. The European standard also does not have a function that was to become important in Japan – and increasingly all over the world -, mobility. “The Japanese already thought of the system in such a way that the TV can be captured by a cell phone or any other mobile equipment.”

The researchers from the Mackenzie University concluded that the Japanese system is the most robust and reaches the houses with a stronger and more perfect signal. Being made up of various islands, in Japan the distribution of the signal is handled by means of free-to-air TVs, with a small share of cable and satellite . The Japanese system also proved to be more robust in the sense of not receiving interference from electronic equipment. Its general condition is more like the Brazilian one , besides being suited to mobility. The Brazilian option should take mobility into account, because the number of cell phones in operation reached 83 million units last year.

“The Japanese standard is the result of an historical evolution. They absorbed the good things and learnt with the limitations and deficiencies of the European standard”, explains Bedicks, from Mackenzie. “The Europeans, in turn, did the same thing with the Americans.” Various researchers that are studying Brazilian digital TV have this same view. Many believe that the Japanese model, with the Brazilian innovations, may become an international system. But, in the last few months, Americans and Europeans have beckoned with modifications to their respective standards that could make them more advanced.

Be that as it may, the modulation system of the Japanese system is the same as European – known as Orthogonal Frequency Division Multiplex (OFDM) -, but with modifications that make it more advanced. The modulation system is what transforms the electric signals into electromagnetic waves. It was at this point that the consortium coordinated by Bedicks proposed a new transmission and reception system based on the Japanese modulator. “We made modifications in the hardware and the software that leave the system even better and make possible a more advanced correction of errors”, Bedicks says.

With the name of BSTOFDM Turbo Code, the system sets out to become more robust in terms of reception and emission signals that the Japanese one itself. To finalize this system, the Mackenzie brought together 25 researchers, among  professors, students  and people specially hired for the project. The group was also made up of researchers from the LSI-USP and from the Federal University of Paraíba (UFPB). As supporting companies, those taking part were Samsung, NEC, TVA and Superior Tecnologia em  Radiodifusão  (STB) from the electronics complex in Santa Rita do Sapucaí, Minas Gerais. This company from the state of Minas Gerais produced the digital TV transmitter that was installed in the tower of TV Cultura and intends to format a production line as soon as the SBTVD is defined.

Both USP’s access terminal and the Mackenzie’s modulation system were integrated with the programs called middleware, extremely important for digital TV. It is responsible for receiving the flow of bits, understanding them, and identifying what is sound, video, images and interactivity and data that flow through the system. The middleware is also above the operating system, which can be Windows, from Microsoft, or  Linux, free to use. In short: everything that is done in the new TV passes through the middleware.

“The way how the interactive content goes to the screen is defined by the middleware”, explains Guido Lemos de Souza Filho, from UFPB’s Information Technology Department and the coordinator of the Flex TV consortium, the name of the new middleware that is an alternative to the systems of the foreign standards. Although it is Brazilian and has the possibility of generating up to six patents and 40 registrations of software, Flex TV was written in the Java computer language, much used on the Internet and in cell phones. In this case, royalties would be paid, about US$ 1 per terminal, to the American company Sun.

“In our system, we can also work with the Nest Context Language (NCL) language”, says Souza Filho. This language was developed at the Pontifical Catholic University of Rio de Janeiro (PUC-Rio). Under the coordination of Professor Luiz Fernando Gomes Soares, from PUC-Rio’s Telemedia Laboratory, this consortium developed the NCL language for digital TV to be used with Flex TV. “The vantage of this language is that we wouldn’t need to pay royalties, because it qualifies for the free software modality”, Soares says.

Another proposal for middleware arose in another consortium, this time under the coordination of Professor Luís Geraldo Meloni, from Unicamp’s College of Electrical Engineering. Called Jangada (raft), it is based on the equivalent European system. “The name was a reference to the fact that one of the applications developed was an Internet browser for the TV”, says Meloni, who led a group of 30 researchers in which also took part some from Fitec, a technological research foundation from Recife, Pernambuco, which likewise has laboratories in Campinas, the State University of Londrina and Rcasoft, a company from Campinas. The middleware of the group from Unicamp was integrated with USP’s access terminal and is one of the options to be analyzed by the Digital TV Development Committee.

Meloni also led a consortium that studied the so-called return channel or interactivity. By this channel, the TV viewer will be able to receive or to ask for available information, use the Internet, vote, or choose alternative proposals in a program of the broadcasting station, besides buying products shown on the screen. The problem is that this interactivity does not travel by a transmission channel, like Channel 11, for example.

It needs another TV channel or to travel via cell phone, fixed telephony, radio, electricity network, or new systems like Wi-fi or Wimax, a system in which a network around an antenna will be able to serve television sets in a radius of up to 60 kilometers. “Our proposal includes the use of the Wimax technology adapted to the VHF-UHF frequency range, used today in free-to-air television.” Accordingly, the project may result in requesting several patents and software registrations. For this project, Meloni coordinated 80 researchers, including groups from UFRJ, the Advanced Studies in Communications Institute of Campina Grande, in Paraíba, from Fitec, from Telefônica and from Samsung, besides from Linear, a company that, also from the town of Santa Rita do Sapucaí, in Minas, produces and exports digital transmitters for use by American TV broadcasting stations.

Another well-developed area in the researches were the content systems. Fernando Carvalho Gomes, from the Federal University of Ceará, led a consortium that developed interactive contents like the T-mail, to exchange messages between TV viewers, besides software that make it possible to diarize and personalize the programming. This will be important, because the terminals will have to have a sort of hard disk, as in computers, in which a program or TV news can be interrupted, to answer a telephone call, for example, and then carry on from where it stopped, or to record something that one cannot watch at that moment.

He also developed the TV-vote. “It’s an application with all the security requirements for voting, for a person to vote only once in polls, referendums etc. The group is preparing patents to be deposited in the United States and in Europe. The University of Fortaleza (Unifor), the Atlantic Institute, the Federal Technological Education Center of Ceará (CEFET-CE) and Omni, a video content company, took part in this consortium.”