With the growth of smartphone and tablet usage, frequency resources are increasingly falling short of demand. An alternative solution may have emerged in TV white spaces. For use in the 470-to-710-MHz TV bands, for example, a new portable-sized tablet terminal enables IEEE 802.11bg-based radio communication. The goal of the terminal, which was introduced by the National Institute of Information and Communications Technology (NICT), is to support the increase of communications traffic.

NICT’s Android tablet terminal is based on an off-the-shelf terminal and frequency converter, which also were developed by the organization to utilize TV white spaces. The terminal provides an interface in which a network manager can automatically select the optimal frequency according to data traffic in the area. Other functions include the ability to display the white-space availability of each channel and the terminal location on a map by acquiring information on TV broadcasters (primary users) from the white-space database. A power-control function uses location and time to show the different limitations of output power.

Operating on a wide frequency range, TV white spaces avoid interference with TV broadcasts while providing fixed-point and mobile communications. Because that frequency range is lower than existing WiFi and cellular bands, however, it has previously been difficult to miniaturize necessary components and circuits for use in portable devices.