Trend: WiFi in white space

We know what the problems are: Anyone can put up a WiFi network because they operate in unlicensed spectrum, but the downside is that the signal is relatively weak to avoid interference with devices such as cordless phones, and must resort to elaborate multipaths scheme to overcome everyday obstacles such as office furniture. Some have suggested using lower frequency, because lower-frequency signal travels better, but desirable bands in the low frequencies are not readily available.

Michael Calabrese of the New America Foundation has an intriguing idea: White space. TV transmissions use a very powerful signal to reach their targets; it is precisely because of the power of the transmission that TV stations must carefully space the signals they transmit so that these signals are not too close to each other (if they are, thee signals will "bleed" together). The space between TV signals is called "white space," and Calabrese argues that lower-power services such as WiFi could use these white spaces without interfering with or disrupting the neighboring TV signals.

Calabrese first offered this idea five years ago, but there were no takers. Times have changed. The FCC is interested, and is now soliciting public comments on the scheme. Intel has conducted several technical studies that show that the unlicensed networks could operate in the white space and achieve better signals than current WiFi--without interfering with TV signals.

For more on WiFi in the white space:
- read Mark Gimein's BusinessWeek report