Mommy, What's a White Space?

The wireless possibilities of white-spaces spectrum are coming into focus as Google gets into a 45-day public trial of its database with the FCC and the IEEE serves up a standard for deploying the technology in rural and under-served regions. So, what exactly is white-spaces spectrum in the first place? Technically, the term harks back to the guard bands (white spaces) used between UHF analog TV channels. In the U.S., more space in the upper 700MHz UHF band has opened up as broadcasters use digital transmission mechanisms to deliver more channels in less spectrum. These are the white spaces that Google wants to map in its new database. Google chairman Larry Page described white-space technology as Wi-Fi on steroids as far as back as 2008, envisioning easy access to cheap spectrum that could enable a new wave of wireless ISPs. That doesn't mean, however, that you'll be able to connect to this technology using current 802.11 Wi-Fi radios. The IEEE defines white space network technology as the 802.22 standard, and devices that can take advantage of the technology will need upper-band 700MHz radios and a client on board to find the network. The TV frequencies will give white-spaces networks much greater range than Wi-Fi too. The IEEE expects each wireless regional area network (WRAN) to deliver 22 Mbit/s to 29 Mbit/s typically over a 10 km to 30 km radius. Initial uses will tend to be in fixed applications like wireless backhaul or mostly stationary uses, just as you would connect to Wi-Fi in a coffee shop. Building out a national white space network that includes mobility is going to be a bigger challenge. — Dan Jones, Site Editor, Light Reading Mobile