Top officials at the Defense and Transportation departments sharply criticized the Federal Communications Commission for giving the go-ahead for a new hybrid cellular and satellite network that could interfere with Global Positioning System navigation and timing elements. FCC failed to consider sufficient input from federal stakeholders, they said.
In addition, Deere and Co., which manufactures farm and construction equipment, told FCC the network planned by Reston, Va.-based LightSquared could cause "devastating interference" to the GPS systems it has developed for precision farming. Those systems reduce the cost of food production in the United States by as much as $3 billion a year, the company said.
Deputy Secretary of Defense William Lynn and Deputy Secretary of Transportation John Porcari said in a letter to FCC Chairman Julius Genachowski last Friday their departments were not "sufficiently included" in an FCC ruling in January that conditionally allowed LightSquared to begin developing its nationwide broadband network, which includes 40,000 cellular towers and a satellite launched in November 2010.
Lynn and Porcari said the LightSquared terrestrial network increases the potential for intererference to GPS receivers. FCC needs to include the two departments as tests are conducted through June, they said.
FCC's plans for LightSquared demonstrate "lack of inclusiveness regarding input from federal stakeholders. In particular, active engagement with DoD and DOT, the national stewards and global providers of the [GPS] services, is essential to protect this ubiquitous defense, transportation and economic utility," the letter said.
The regulator should ensure that a "comprehensive study of all potential interference" by the LightSquared network is included in the studies done by the company and the GPS Industry Council, the department leaders said.
Jeff Carlisle, executive vice president for regulatory affairs at LightSquared said in a statement, "We are sensitive to concerns about potential interference, which is why we have fully committed ourselves to a comprehensive process that will ensure our network can coexist with GPS devices and agreed to only launch commercial operations when this process is completed to the FCC's satisfaction."
Carlisle added, "As part of this effort we are cooperating with federal agencies, the GPS community and GPS engineers in a transparent and technically accurate testing program to address issues relating to GPS receivers. We are also providing equipment and personnel to the U.S. Air Force's Space Command, NASA and other federal agencies to help them begin their own testing processes."
GPS operates in the 1559-1610 MHz frequency bands and the LightSquared network operates in the nearby 1626.5-1660.5 MHz band. In filings with the regulator, aviation groups such as the Aircraft Owners and Pilots Association said FCC failed to evaluate the "substantial public interest harms" the company's network would cause by "significant desensitization" of GPS receivers.
The Federal Aviation Administration plans to build its Next-Generation Air Transportation System around GPS, which will provide highly precise signals needed for en route navigation and landings.
Deere, in its filing with FCC Tuesday, said the LightSquared system could knock out its StarFire precision farming systems, which use specialized equipment to increase the accuracy of GPS signals from 65 feet to 4 inches. The system helps farmers precisely determine the amount of seed and fertilizer needed throughout their operations, Deere said.
LightSquared said interference is not caused by its system, but by sensitive GPS receivers that "see" into the frequency band used by LightSquared. Not all GPS receivers do that, Carlisle said, and one possible mitigation strategy is to replace GPS receivers that pick up the LightSquared signal.
The LightSquared industry group filed its first progress report with the FCC March 15, detailing test plans and types of receivers it expects to use in those tests. The final report is due in June. Federal representatives on the working group include: Michael Biggs, FAA senior engineer; Air Force Capt. Anil Hariharan, chief of GPS spectrum engineering in the joint service GPS Directorate; Fred Moorefield, technical director and director of strategic planning in the Air Force Spectrum Management Office; and Brian Ramsay, spectrum policy specialist in the NASA Space Communications and Navigation Program Office.