New LightSquared plan to reduce GPS interference greeted with skepticism at House hearing

LightSquared's latest proposal to keep its planned broadband wireless network from interfering with GPS signals met with skepticism at a congressional hearing Thursday.

After multiple tests showed the network, as originally planned, would disrupt all GPS applications, the startup floated a fix earlier this week that it said would keep its initial transmissions at a safe distance from GPS frequencies.

The Defense Department, which developed and operates GPS and relies on the technology for all its operations, considers LightSquared network signals to be equivalent to a GPS jammer, according to a committee briefing memo prepared for today's hearing of the House Transportation and Infrastructure Committee Subcommittee on Aviation.

LightSquared said tests so far have shown that the lower block of frequencies it plans to use in its nationwide network of 40,000 base stations is largely free of interference issues, with the exception of a limited number of high-precision GPS receivers. The GPS system operates in the 1559-1610 MHz band and LightSquared operates in the nearby 1526-1536 MHz and 1545.2-1555.2 MHz bands.

The company said it will limit its initial operations to the 1526-1536 MHz band, which is "located farther away from the GPS frequencies, greatly reducing the risk for interference."

An aviation advisory group, the Radio Technical Commission for Aeronautics, told the Federal Aviation Administration on May 26 that in tests it had determined operations of LightSquared's transmitter in the lower band are "compatible with aviation GPS operations." But Margaret Jenny, president of RTCA, told the hearing that her group looked only at LightSquared transmitter broadcasts with a power of 1.6 kilowatts instead of the 16 kilowatts authorized by the Federal Communications Commission. She warned that higher power levels would render the results "far worse."

Jeff Carlisle, executive vice president for regulatory affairs at LightSquared, assured the panel the company would operate only at 1.6 kilowatts and not the higher power levels authorized by FCC, adding cellular equipment manufacturers do not even offer 16-kilowatt transmitters.

LightSquared eventually would like to operate in its upper frequency band, but Carlisle told the hearing that the company has no intention of compromising the safety of aviation or maritime navigation systems, both heavily dependent on GPS. He vowed LightSquared will work with the GPS industry to resolve interference issues with GPS receivers, including development of filters to mitigate interference.

Phil Straub, vice president of aviation engineering for receiver manufacturer Garmin International, said such filters do not exist, and Thomas Hendricks, senior vice president of safety, security and operations at the Air Transport Association, said it would take a decade to develop them, hobbling full rollout of the Federal Aviation Administration's GPS-based Next-Generation Air Transportation System, which has a $20 billion price tag.

When FCC granted LightSquared a waiver to start operation this January, it directed the company to conduct interference tests and deliver a report by June 15. LightSquared requested and was granted an extension until July 1.

Roy Kienitz, undersecretary for policy at the Transportation Department, said the proposal LightSquared unveiled this week will require another round of tests on the lower band frequencies and their potential impact on GPS.

Craig Fuller, president of the Aircraft Owners and Pilots Association, a trade group that represents private pilots and corporations that operate their own aircraft, blamed FCC for the interference problems detailed at the hearing. He urged the committee to direct FCC to get a "sign off" from Defense and Transportation before allowing LightSquared to proceed with its network deployment.

Carlisle emphasized the high financial stakes LightSquared has in development of its network, with a $14 billion investment planned over the next eight years, projected to create 15,000 jobs a year in each of the five years it will take to build it.

Kienitz said airlines also have high stakes and cannot afford any interference with their signals. "GPS has to work 100 percent of the time when you are landing airplanes," Kientz said.

Rep. Thomas Petri, R-Wis., charman of the subcommittee agreed, and said, "there is no room for error" in aviation.