Former Motorola exec backs airwaves auction

* No technical impediments to sharing network -Roberson

* FCC chief says timing can save costs

WASHINGTON, Aug 25 (Reuters) - A former top Motorola Inc MOT.N executive supports auctioning a chunk of wireless airwaves highly sought after by public safety officials, putting himself at odds with his former company.

Dennis Roberson, a former chief technology officer at Motorola, a supplier of wireless equipment to customers such as emergency response services, said auctioning the so-called D block to companies such as T-Mobile USA, who paid for his analytical study, is the best way to build an interoperable broadband communications network for first responders.

“There are no technical impediments to providing public safety users immediate access to commercial networks during periods when the network is at capacity,” Roberson said in a filing with the Federal Communications Commission, dated Aug. 24.

His study, which was funded by T-Mobile USA, a unit of Deutsche Telekom AG DTEGn.DE, is the latest maneuver in the tussle over who should control and access the D block.

But Schaumburg, Illinois-based Motorola backs public safety groups trying to block an auction. Public safety groups want the D block for themselves and do not want to rely on commercial operators opening up the network during an emergency.

The spectrum has become the object of a tug-of-war among wireless companies, public safety groups, lawmakers and regulators at the FCC who have reassured police and firefighters they will have access to the airwaves if there is another disaster akin to the September 11 attacks or Hurricane Katrina.

“With an appropriate FCC regulatory framework that would require sharing of spectrum during times of emergency, a robust system that serves both public safety and commercial users can be realized,” Roberson said.

Roberson is currently vice provost and research professor with the Illinois Institute of Technology.

T-Mobile USA, the No. 4 U.S. mobile operator, and top FCC officials favor auctioning the D block, a leftover of the 1998 spectrum auction which generated about $19 billion in proceeds for the U.S. government.

T-Mobile USA is seeking more spectrum to beef up its wireless data services and keep up to speed with its much bigger rivals AT&T Inc T.N and Verizon Wireless, a venture of Verizon Communications Inc VZ.N and Vodafone Group Plc VOD.L.

AT&T and Verizon have thrown their support behind the public safety groups, who also have the backing of Senate Commerce Committee Chairman Jay Rockefeller.

But some FCC officials are urging public safety groups to work with wireless companies during the build-out of that area of the spectrum for advanced wireless technology called 4G in order to minimize costs.

At an event in Minnesota on Tuesday to discuss the National Broadband Plan, FCC Chairman Julius Genachowski said there would be significant cost savings if a public safety network is built out now with the wireless companies.

“We can save lives and save money if we move quickly,” he said. (Reporting by John Poirier, editing by Matthew Lewis)