Government Agencies to Push for Further Testing, in LightSquared Hearing

"We are concerned that if terrestrial broadband transmissions are allowed anywhere in the MSS-band, they will disrupt existing GPS uses including precision agriculture and many scientific and surveying systems such as those that NASA, NOAA, Department of the Interior, and others rely on,” said Peter Appel, administrator of the Research and Innovative Technology Administration in the Department of Transportation, in his written testimony. Earlier this summer, LightSquared filed revised plans for its rollout, initially beginning service in the lower 10 MHz of the L-band, furthest away from GPS signals. Appel also said additional testing and analysis of those plans are needed. The FCC is reviewing the revised plans and comments on them. LightSquared recently said it didn’t think further testing would be needed.

NASA also isn’t yet convinced. None of the mitigation options offered, including beginning in the lower part of the band, “have yet been demonstrated to be effective in mitigating potential interference to GPS,” said Victor Sparrow, director of spectrum policy for NASA, in his testimony. “Although limited testing was conducted by the [technical working group] on the susceptibility of some GPS devices to the use of only the lower 10 MHz LightSquared channel, limitations -- such as filters that have yet to be designed or are theoretical or speculative in nature -- prevented adequate testing of this mitigation approach. NASA believes it would be premature to allow the use of only the lower 10 MHz channel as a solution, until testing has been completed and it is established that there is no negative impact on GPS users."

The National Oceanic and Atmospheric Administration would like more testing “in order to assess the GPS interference concerns in the lower 10 MHz of the band and to establish whether there are any feasible mitigation strategies,” said NOAA Deputy Undersecretary Mary Glackin in her testimony. “We also encourage commercial entities with interests to work with LightSquared toward a possible resolution, though any proposed mitigation must be subjected to full testing. The Administration appreciates LightSquared’s offer to not transmit in the upper 10 MHz of its band, right next to GPS, and strongly supports efforts to identify alternative means of achieving the intended purpose of the signal that was planned there."

The Science Committee “will review the results of recent testing on the impact of the LightSquared network on the GPS signal,” the committee majority said in a hearing charter released Wednesday: “Potential interference could disable the GPS signal used for critical U.S. Government services and science missions such as the Next Generation Air Transportation System, Earth and space science missions, communications and navigation, space mission operations, weather prediction and climate observation, search and rescue, disaster response and public safety, navigation, geodesy, and marine research platforms and services.” The committee also “will examine measures and costs necessary to implement and prioritize mitigation strategies” at federal departments and agencies, it said.

The hearing isn’t likely to settle the conflict over “whether we are looking at an engineering challenge (building better filters, shaping cell tower antennas) or an insoluble physics problem (whether the sheer power of terrestrial cell signals inevitably overwhelms GPS devices),” said Democrats of the House Science Committee in a memo dated Tuesday. “Until there are clearer answers to whether the LightSquared versus GPS conflict is about engineering or physics, we cannot know whether we can have both thriving GPS services and more broadband to spur innovation and employment.”

LightSquared’s testimony emphasizes the public benefit of the company’s planned wireless network. “What LightSquared is doing is making a massive private investment in critical U.S. infrastructure, making better and more efficient use of spectrum, and enabling wireless competition, all to the benefit of American consumers, public safety, and the nation as a whole,” said Executive Vice President Jeff Carlisle in written testimony. “We are bringing 40 MHz of spectrum to be used for broadband services -- a significant down payment on the FCC’s ten year goal” of 500 MHz, Carlisle said. “No other company has such a significant slice of airwaves that is ready to deliver network capacity to our spectrum-starved nation, and no other company could conceivably offer this broad coverage in the same timeframe."

LightSquared is working hard -- and at its own expense -- to ensure the network and GPS can coexist, Carlisle said. “The interference issue … is not a physics issue. It is a technology design issue and can be addressed through proper design,” Carlisle said. “Contrary to the claims of some of the GPS manufacturers, there are technical and operational solutions that will allow us to deploy our network while retaining the benefits provided by using these devices.”