Google has unveiled a searchable map of the available white-space spectrum in the U.S. The company said this new effort is in order to help promote dynamic spectrum sharing.

The FCC last month announced the public testing period of Google’s new database, which will last 45 days before the Commission will decide if the map is accurate and helpful to the general public.

White space is the term used to describe unused bandwidth in unlicensed spectrum used for TV broadcasts. White space spectrum can be available in rural areas in lower frequency ranges, making it valuable for its good propagation characteristics.

When the FCC in 2011 made white space available without having to apply for experimental license, the available spectrum was highly touted by the likes of Google, which wanted to use it to boost wi-fi signals.

The FCC employs restrictions on white space bands, which can cut down the amount of usable bandwidth in a 6 MHz band by as much as 25 percent, greatly drive up the cost of deploying a network on that spectrum and reduce broadband speeds.