New tablet terminal opens prospects for overcoming spectrum limits

Researchers in Japan say they have developed a portable tablet terminal able to communicate within unused “white space” bands in the TV transmission spectrum.

The development by the National Institute of Information and Communications Technology (NICT) means that such devices will be able to break free from the current limited number of frequencies by using the white space between the bands already in use.

NICT say the new Android tablet is based on an off-the-shelf terminal and a frequency converter newly developed by them.

It means that frequencies in both TV and 2.4 GHz bands are available using an original wireless LAN system of the IEEE802.11 b/g standard.

An additional benefit is the tablet terminal can operate in frequency ranges considered not to interfere with TV broadcasts, and can automatically select the best frequency according to data traffic and other factors through control by the network manager.

It also includes a function to display the white-space availability of each channel and the terminal location on a map by acquiring information on primary users – TV broadcasters – from the white-space database.

Challenges in the past have been in miniaturising the technology to enable small portable devices to access TV spectrum using wireless LAN, so experts say this development will be a big step forward for portable communications.