The fight to protect GPS

WASHINGTON, D.C. — If the communication company LightSquared goes ahead with its plan to install ground-based transmitters throughout the United States, it could mean catastrophic and potentially fatal issues for users of GPS.

This was one concern expressed at a June 23 Congressional hearing into the conflict between LightSquared and users of GPS because of the closeness of frequencies between what GPS uses and what the Federal Communication Commission has granted to LightSquared.

Interference could result in grave problems with aviation’s use of GPS, a decade delay in development of the Next Generation Air Traffic Control System (NextGen), reduced effectiveness of military flying, severely hurt Coast Guard search and rescue efforts and the monitoring of sea traffic programs, and pose problems for any electronic unit, such as iPads, iPods, phones and other devices that include GPS.

Tests relating to potential interference were conducted by the Radio Technical Commission of Aeronautics (RTCA) and showed only minor problems in the lowest five frequencies, with greater potential problems in the upper level of the spectrum. Speaking for LightSquared, Jeffrey Carlisle told committee members the company now plans to use only the lowest five frequencies, but might have to move into the higher ones in future years to handle volume. In the lower five frequencies there is no problem with 99.5% of the transmissions, he added.

But that number still concerns aviation officials, said Craig Fuller, president and CEO of the Aircraft Owners and Pilots Association (AOPA), who pointed out that aviation cannot be satisfied with anything less than 100%. Between general aviation and the airlines, air traffic control is in contact with so many aircraft that a potential failure of even just .5% could mean 500 to 1,000 aircraft a day might face a failure in GPS because of interference from LightSquared’s cell phone network.

In his opening statement, Fuller said other GA organizations — including the National Business Aviation Association, General Aviation Manufacturers Association, the Experimental Aircraft Association and others — endorsed his comments.

Thomas Hendricks, an executive with the Air Transport Association, echoed Fuller’s statements, saying that 86% of all air carrier and commercial air cargo aircraft now have GPS equipment and that ATA would oppose anything that would endanger flights. To wait for further tests on frequencies could result in a decade delay in implementation of NextGen, he warned.

Carlisle, in the question and answer period, said filters are available for some who use GPS that could further assure no frequency interference. These, however, have not been tested in the other frequencies LightSquared would want to use in the future. The process of determining filter requirements, developing them, and going through the long process of certifying them for use on aircraft could take decades and raise the costs.

In urban areas, GPS could be unusable below 2,000 feet. When ask by a member of Congress what the company considers “urban,” Carlisle could not provide a specific size.

The hearing was a joint session of the Subcommittee on Aviation and the Subcommittee on Coast Guard and Maritime Transportation. Rear Admiral Robert Day Jr. said almost every mission of the Coast Guard relies on GPS. Not only is this essential to search and rescue operations to know the precise position where help is needed, but also is necessary for security reasons to keep track of maritime vessels to know where ships depart, their routes, and destinations. Referring to the closeness of the frequencies, Day said: “The farther away from GPS frequencies the better.”

Fuller submitted AOPA’s written testimony and used his time as a witness to talk about the process of the agencies involved that permitted the conflict to reach its present stage. The FCC granted LightSquared a “conditional waiver,” which is highly unusual, setting the stage for the opposition forces to unite in a new group, the Coalition to Save Our GPS.

NBAA, GAMA and other aviation alphabet groups also submitted written statements. In NBAA’s written statement, Ed Bolen, president and CEO, cited the worries of the business community over severe interference to GPS but also said there are concerns internationally. The International Civil Aviation Organization (ICAO) sent a letter June 13 to U.S. officials expressing that organization’s “grave concerns.”

The written statement from GAMA President and CEO Pete Bunce boiled down the opposition this way: “Simply put, if LightSquared’s proposed service goes into effect, it will compromise public safety, transportation systems, and aeronautical emergency communications.”

The Congressional committee’s responsibilities are primarily oversight. Rep. Tom Petri (R-Wis.), chair of the Aviation Subcommittee, asked all witnesses if, in their opinions, any legislative action was needed. Fuller said it would be helpful if all government agencies — the Department of Defense, FAA, and other agencies — would have to sign off on something like frequency allocation before going ahead.

LightSquared is building a wireless broadband network using a technology called Long Term Evolution (LTE). It plans 40,000 ground-based stations and will broadcast with a power 4 billion times more powerful than GPS.

Charles Spence is GAN’s Washington, D.C., correspondent.

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