TV white spaces technology until now has been implemented as a means of providing fixed broadband wireless service. But Japan’s National Institute of Information and Communications Technology (NICT) said today it has developed the first equipment designed to support portable broadband service in TV white spaces spectrum. The company stopped short of using the word “mobile,” however, suggesting that the device may not function correctly at highway speeds but instead would support nomadic use where a user would be stationary, but could move from one location to another.
According to a NICT announcement issued today, the device is a “portable-size Android tablet terminal” that supports wireless LAN communications using the 2.4 GHz band as well as in TV white spaces spectrum in the 470-710 MHz range. That spectrum is well suited for transmitting broadband wireless communications over relatively great distances, and in many rural areas, numerous TV broadcast channels are vacant and available for broadband wireless use.
NICT’s product seems to be very much a prototype, however. In announcing the device, the organization notes, for example, that “it is difficult to miniaturize components and circuits for portable devices due to [the] lower operational frequency than existing WiFi or cellular bands and [the] relatively wide frequency range of 470-710-MHz.”
Fixed broadband wireless equipment that has already been deployed in TV white spaces bands has used dynamic database technology to determine which channels are vacant in a particular area, thereby enabling the equipment to configure itself to use vacant channels. But a portable device could cross multiple TV broadcast markets, and the NICT release suggests that further development is required to enable a portable white spaces device to function properly.
“Technology to avoid interference with TV broadcasts is necessary to be implemented in portable devices,” wrote NICT, noting that it will “evaluate the propagation characteristic using this tablet terminal and offer the information that contributes to a technical reference and a rule designed for TV white space operation.”
The decision to include 2.4 GHz technology in the portable TV white spaces device would seem to be a smart one, as it could take some time before TV white spaces technology is widely deployed – and in urban areas, there may be little or no vacant TV spectrum.
The U.S. initially led the way in developing TV white spaces technology by supporting some of the earliest trials of the dynamic database technology that made it feasible to use the spectrum for broadband wireless communications. Some people, including former FCC Chairman Julius Genachowski, hoped this would give U.S. equipment manufacturers a leg-up in this market.
But NICT is one of several non-U.S. technology development organizations that have jumped on the TV white spaces opportunity and could provide significant competition to U.S.-based companies like Carlson Wireless and Spectrum Bridge that have been early movers in the TV white spaces market.