A multibillion dollar proposal to create a 4G wireless broadband network in the United States could interfere with several scientific services that use the Global Positioning System (GPS), including forecasting the weather, monitoring climate change, and tracking volcanic activity, U.S. federal officials told a Congressional panel yesterday. Their concerns are the latest in a crescendo of objections raised against the proposal by federal agencies and providers of GPS-based services.
LightSquared, a company based in Reston, Virginia, has already spent over $4 billion to set up the network, which would provide improved cell phone and Internet connectivity across the country. The network would be supported by LightSquared's geostationary satellites and some 40,000 ground transmitters operating in a frequency band adjacent to the band used by GPS, a satellite-based navigation system used the world over.
That plan is awaiting a final green light from the Federal Communications Commission. In the meantime, however, it has run into considerable opposition from the government and the private sector. The Federal Aviation Administration has pointed out that the LightSquared network will intrude upon its Next Generation Air Transportation System, impinging on the FAA's efforts to make flying safer. Commercial providers of GPS services have raised concerns that LightSquared's transmitters will cause problems for millions of GPS devices used in everything from car-navigation systems to fishing boats. These concerns have been validated by tests conducted earlier this year by a technical working group that included representatives from LightSquared and the GPS industry.
At a hearing before the House of Representatives Committee on Science, Space, and Technology, officials from NASA, the National Oceanic and Atmospheric Administration and the U.S. Geological Survey (USGS) expressed concerns about LightSquared's impact on federal science activities. "NASA relies on GPS technology to monitor and improve our understanding of earth science, including climate change and solid Earth hazards, such as earthquakes and volcanic activity," Victor Sparrow, director of NASA's Spectrum Policy and Planning Division, told the committee. David Applegate, USGS associate director for natural hazards, said LightSquared's proposal would jeopardize the operations of several "high-precision GPS stations" that are used for "earthquake monitoring for at-risk urban areas in southern California, the San Francisco Bay Area, and the Pacific Northwest."
The results of tests by the technical working group, submitted this summer to the Federal Communications Commission, found that 31 out of 33 high precision GPS receivers were significantly affected by LightSquared's signal. In response, LightSquared has proposed to operate its transmitters in a frequency band farther away from the GPS spectrum, a step it says will correct the problem. In addition, it has offered to share with the owners the cost of upgrading any GPS receivers still affected by LightSquared's signal.
Federal officials testifying yesterday were not convinced that LightSquared's modified plan would address their concerns. Lawmakers on the panel seemed equally skeptical. "Unfortunately, no testing has been done on this modified plan," remarked the committee's chairman, Representative Ralph Hall (R-TX). "Additional testing should be required before the FCC allows LightSquared to begin commercial service," he added.
The ranking Democrat on the panel, Representative Eddie Bernice Johnson (D-TX), hoped that a compromise would be worked out between GPS users and LightSquared. The question before the FCC was "whether GPS can thrive side-by-side with a ground-based broadband network," she said. "I sincerely hope that they can coexist."