New Spectrum from Old
The global switch from analog to digital television has created an unusual opportunity, opening up portions of the radio spectrum around the world that have been off limits to anyone but broadcasters for decades. These newly vacant “white spaces” can be found from 52 to 806 megahertz, and telecommunications companies hope to be able to use some of them for long-range broadband wireless connections. In the United States, the Federal Communications Commission announced rules for unlicensed use of white spaces in September, but a number of pilot systems have already been deployed. The first such public network, introduced in rural Virginia by Spectrum Bridge in October of last year, used white-space frequencies to connect Wi-Fi hot spots to the Internet.

One significant difficulty in opening up white spaces to mainstream consumer use is that the exact frequencies available vary from place to place, largely depending on the bands used by local TV stations.
Consequently, researchers are focusing on making wireless equipment smart enough to figure out which frequencies it should be using. At Microsoft Research, Ranveer Chandra (see TR35, September/October 2010) has developed a prototype system in which base stations determine their location using GPS and then check the Web to find out which radio bands are allocated to local broadcasters.
Keep Reading
Most Popular
The inside story of how ChatGPT was built from the people who made it
Exclusive conversations that take us behind the scenes of a cultural phenomenon.
How Rust went from a side project to the world’s most-loved programming language
For decades, coders wrote critical systems in C and C++. Now they turn to Rust.
Design thinking was supposed to fix the world. Where did it go wrong?
An approach that promised to democratize design may have done the opposite.
Sam Altman invested $180 million into a company trying to delay death
Can anti-aging breakthroughs add 10 healthy years to the human life span? The CEO of OpenAI is paying to find out.
Stay connected
Get the latest updates from
MIT Technology Review
Discover special offers, top stories, upcoming events, and more.