Microsoft isn't letting a little Federal Communications Commission (FCC) rejection keep it down.
The company submitted a device to the agency today that shows the potential of using the interference buffer zones between television channels, called "white spaces," for wireless broadband services.
"We remain confident that the unused channels in the television spectrum band can successfully be used without harmful interference to incumbent licensees, such as television and wireless microphone services," Microsoft said in a statement.
The new submission comes only days after an FCC report cast serious doubts on the ability of "smart radios" to detect and avoid television signals in white spaces. The agency based its report on its testing of a prototype Microsoft device.
According to Microsoft, the prototype device tested by the FCC was not working properly because an internal component was broken. Testing on a spare prototype, Microsoft claims, shows the device can detect and avoid television signals.
The FCC tested two devices submitted by the White Space Coalition, which includes Microsoft, Google and several other technology companies. The FCC concluded the first prototype was "generally unable" to sense wireless microphones while the second device delivered mixed results.
"Prototype white space devices submitted to the commission for initial evaluation do not consistently sense or detect TV broadcast or wireless microphone signals," the report concludes.
But Microsoft said Monday one of the prototypes tested by the FCC for digital television signals contained a scanner operating at a "severely degraded" level. Microsoft said the damaged scanner accounted for the poor performance of the device.
An identical prototype in the FCC lab delivered much better results, Microsoft said.
"Microsoft's testing of the spare prototype device it had previously submitted to the FCC revealed that in the FCC's laboratory, the spare device was able to detect digital television signals at the power level that we had stated," the company stated.
"And with some adjustments, this device detected wireless microphone signals as we had indicated that it would."
Companies such as Microsoft and Google hope to eventually use white spaces to develop both licensed and unlicensed wireless devices and services.
Licensed use could include delivering wireless broadband, while free, unregulated spectrum is currently used by garage-door openers, baby monitors, microwave ovens, remote controls and, increasingly, wireless LANs.
The white spaces could be utilized as early as February 2009 when broadcasters move to digital signals.
The National Association of Broadcasters (NAB), which opposes the use of white spaces for purposes other than interference buffer zones, said Monday the initial FCC report should stand.
"The FCC performed rigorous tests, and we are confident its report is accurate. By continuing to press its self-serving agenda, Microsoft is demonstrating a willingness to play Russian roulette with America's access to interference free television reception," NAB spokesman Dennis Wharton said in an e-mail statement.