WASHINGTON -- A Senate committee yesterday passed a bill that would direct two federal agencies overseeing the nation's wireless spectrum to conduct an inventory to determine how the various bands of airwaves are being used.

The Radio Spectrum Inventory Act, introduced by Sens. John Kerry (D-Mass.) and Olympia Snowe (R-Maine), cleared the Commerce Committee by unanimous vote. The bill now awaits consideration by the full Senate.

The same day, a bipartisan group of House lawmakers introduced a similar bill.

Both bills would require the Federal Communications Commission and the National Telecommunications Information Administration, a division of the Commerce Department, to conduct an inventory of the spectrum allocated to government agencies and the private sector, and make that data available to the public on a Web site.

The agencies would also be required to submit a report to the relevant congressional committees in both chambers.

There is little controversial about the spectrum bill. As policy makers grow increasingly concerned over the United States falling behind other countries in broadband deployment, they also realize that there is not a one-size-fits-all solution to the broadband problem. Some technologies are better suited to certain areas than others. In rural America, where long distances and rugged terrain have impeded fixed-line broadband, many look to wireless networks, which deliver faster speeds the more spectrum they can access, to bridge the digital divide.

But with the hodgepodge of licensed and unlicensed spectrum allocations over the years, there is widespread agreement that a resource considered central to ubiquitous broadband is not being put to the most efficient use.

"We certainly need a process of conducting the inventory of unused and underused spectrum to complete a national broadband plan," said Kay Bailey Hutchison, the Ranking Republican on the Commerce Committee and a cosponsor of the bill.

The House bill introduced yesterday casts a wider net than the Senate version that cleared committee. In the House version, the FCC and NTIA would be required to inventory all spectrum falling between the frequencies of 225 MHz and 10 GHz. The Senate bill limits its range to 300 MHz to 3.5 GHz, though an amendment modified the bill to make it clear that would be a minimum range for the agencies, inviting them to broaden their inventory.

The House version also asks for recommendations for how to reallocate under-utilized government licenses. The Senate bill only asks for information about the allocations and a contour map displaying signal strength and coverage.

The passage of the Senate bill drew cheers from CTIA, the trade association representing the wireless industry, whose members' businesses are built on spectrum and have long advocated for policy reforms to make more of the resource available.

In a statement, CTIA President and CEO Steve Largent praised Kerry and Snowe for crafting a bill that "identifies where the next allocation of spectrum for commercial use will come from." Largent said he hoped to see an inventory bill pass both chambers this year.

In recent weeks, some experts have taken aim at the widely held notion of spectrum scarcity. They have argued that the limited availability of the airwaves owes to a failure of policy, rather than a short supply of the resource itself.

Presenting their findings last month at an event in Washington, a panel of researchers claimed that spectrum, particularly the bands that belong to government agencies, is grossly underused. They called for a migration to a network-based spectrum regime, where all the airwaves would be pooled in a nationwide database and available on demand to smart devices with GPS capabilities to avoid interference.

Spectrum policy figures to play a key role in the FCC's work drafting a national broadband strategy, a charge it received in the February economic stimulus bill.

Julius Genachowski, who recently took over as chairman of the agency, signaled his commitment to spectrum policies that promote greater access to mobile computing at his confirmation hearing. The FCC is due to submit its broadband roadmap to Congress next February, and with a legislative calendar clogged up with major issues like health care and energy reform, it's unclear when the spectrum inventory bill could come up for a floor vote.

Both versions of the bill would give the agencies six months to complete their inventories, which would only be a start toward any sweeping policy reform to make more efficient use of the spectrum.

"That really only is the first step," Sen. Mark Warner (D-Va.) said at yesterday's hearing. "It's not only who holds the licenses, but what is the utilization of that spectrum."