More than half the population of Brazil lives in remote towns and villages. Many have no telephone connection. But the Brazilian power line network covers almost 95 per cent of populated areas. And wherever there is power, there are usually television sets.
Bearing that fact in mind, the researchers involved in the SAMBA (System for Advanced interactive digital television and Mobile services in BrAzil) project broadcast digital television signals with Java applications embedded in them into the small Brazilian town of Barreirinhas, which is 300km from the nearest major city.
Some 30 Barreirinhas households, in the vicinity of a 3km power line, were equipped with special set-top boxes that enabled them to access the broadcast data. The set-top boxes were also connected to the houses’ mains electricity supply so that the power line could be used by the TV viewer as a means to send instructions back to the system.
‘The broadcast was over the normal television broadcasting system with an antenna and repeater in the town,’ explains Oscar Mayora Ibarra, project coordinator of SAMBA from the Italian research company Create-Net.
The power line limited the return channel to speeds of around 2Mb/sec.
SAMBA also ran a pilot in the small town of Natz in the Italian Tyrol. Natz is in an extremely mountainous area. The small town has power lines but limited internet connection because of the difficulty and cost of reaching it.
With the support of a local television company in Bolzano, SAMBA established a system broadcasting TV signals with embedded Java, once again using the power supply line as a return channel.
This is the first time that interactive television has been piloted in Brazil. But the focus on local communities was what made it especially novel, according to Mayora Ibarra. During the pilot, information from local agencies was broadcast over the system.
‘Interactive digital television is not a competitor for computers with an internet connection. But at a local level, digital television can play a very interesting role. Elderly people can use the television to share information and sports clubs and societies can broadcast their information on a very local basis,’ added Mayora Ibarra.
The researchers say that the SAMBA system can be adapted for delivery over any broadcast standard.
Source: ICT Results