Prototype wireless broadband devices operating in television spectrum were frequently, but not always, able to sense TV stations and wireless microphones operating in the spectrum and avoid causing interference, according to a report released late Wednesday by the U.S. Federal Communications Commission.

The report, a giant step toward allowing new wireless broadband devices to operate in unused TV spectrum, comes after several groups complained that the devices would cause interference. The National Association of Broadcasters (NAB), some mobile-telephone carriers and wireless-microphone vendors have opposed the request by several large tech vendors to allow new wireless devices to operate in unoccupied TV channels.

However, the report also noted that some prototype devices had difficulty finding wireless-microphone signals operating in the TV spectrum during a series of tests conducted over the past year. The debate is likely to continue as the FCC moves forward with its effort to allow devices such as new smartphones to use the so-called white spaces of the television spectrum.

The National Football League, the ESPN network and several lawmakers and churches have also raised concerns about potential interference by new devices in the white spaces. Both sides in the debate have conducted intense lobbying campaigns in recent months.

Tech vendors cheered the FCC report. It is "great news" for tech vendors looking to provide a new avenue for customers to connect to broadband, said Steve Sharkey, Motorola's senior director of regulatory and spectrum policy.

The report came out just hours after FCC Chairman Kevin Martin told reporters that he'd support the use of new broadband devices in the spectrum white spaces. The FCC is scheduled to vote on an order to move the white-spaces plan forward during its Nov. 4 meeting, Martin said.

The report "sets the stage for the FCC to move forward," Sharkey said. "This really shows the commission is taking the issue seriously."

Representatives of the NAB and microphone maker Shure weren't immediately available for comment.

For more than two years, large tech companies and consumer groups have been pushing for the FCC to approve use of the spectrum white spaces. Among the companies and groups calling for the FCC to approve white-space devices are Microsoft, Google, Dell, Hewlett-Packard, Public Knowledge, Free Press and the VON Coalition.

FCC approval of the devices would spur innovation and create new jobs in the tech sector, and allow consumers to have a new option for broadband service, supporters say. The TV spectrum would allow broadband signals to travel significantly farther than the spectrum used by WiFi.