Microsoft Corp., Google Inc. and four other technology companies plan to submit a prototype of a new handheld device to U.S. regulators for testing, as they press the government to free up airwaves for wireless Internet access.

Microsoft is developing the prototype, which the coalition will submit to the Federal Communications Commission's Office of Engineering and Technology, according to a Feb. 5 letter the companies filed with the FCC.

The device would "provide consumer broadband access and networking," the filing said.

The commission is considering whether to let companies offer wireless Internet access on handheld devices that would use vacant television airwaves, known as white spaces.

A law enacted last year requires TV stations to convert to digital technology by February 2009, freeing up their old airwaves.

Microsoft, Google and other coalition members want the FCC to make the vacated airwaves available for wireless-fidelity, or Wi-Fi, Internet access services and other unlicensed uses. Other member companies include Dell Inc., Hewlett-Packard Co., Intel Corp. and Philips Electronics North America Corp.

The FCC invited companies in December to submit prototypes for testing, to determine whether such devices would interfere with TV broadcasts.

The Microsoft prototype is capable of sensing signals that broadcasters are using and would "move to a vacant channel or not transmit at all if one is not available," the coalition's filing said.

The companies filed that information with the FCC to demonstrate that vacant TV airwaves can be used for consumer applications, Microsoft spokesman Eric Hollreiser said.

The prototype device described in the filing isn't related to a possible Zune phone, Hollreiser said in an interview.

Microsoft Chief Executive Steve Ballmer said in November that Microsoft plans to sell a device in the future that combines its Zune music and video player with phone features.