Companies active in the GPS industry have taken a clear position against LightSquared
’s proposed LTE broadband network on 1525 to 1559 MHz spectrum, which tests have shown to cause significant interference with global positioning systems running on 1559 to 1610 MHz. GPS touches a wide range of industries, from fleet and asset tracking to aviation, defense, and field service enterprises.
"The test data discussed today makes clear that there is substantial interference to GPS if LightSquared turns on high-powered terrestrial facilities in the spectrum next door to GPS," Kirkland said. "The data confirm what the industry told the FCC before it granted the waiver, and also confirms that there is no viable technical fix. It's time for the FCC to stop squandering resources trying to find a solution to an unfixable problem. Instead, it should focus its efforts on finding spectrum that LightSquared can operate in—where LightSquared won't interfere with GPS.
"When it comes to broadband and GPS, it's not an either/or situation—the United States can, and should have both. LightSquared says it has other spectrum and it should use it," Kirkland said.
At issue is an unusual waiver granted to LightSquared in January by the FCC's International Bureau allowing the dramatic expansion of terrestrial use of the mobile satellite spectrum (MSS) immediately neighboring that of the GPS—utilizing extremely high-powered ground-based transmissions that tests have shown will cause interference to hundreds of millions of GPS receivers across the U.S.
At the event, Kirkland and government representatives discussed testing conducted to measure interference to GPS receivers used in aviation and other critical government applications. In at least one test, LightSquared failed to deliver test equipment that matches its proposed operations, thus causing optimistic results—and even those optimistic results showed interference.
“You can manipulate the testing scenario to achieve one result or the other,” says Michael King, research director, Gartner
, “but the real-world tests show there’s significant interference when the GPS and LightSquared networks are run simultaneously. And it’s not just an issue of GPS not working properly or being as effective—the GPS receivers shut down completely.”
"It's clearly a good thing that LightSquared is trying to do," Kirkland said. "No one in the GPS industry opposes its goals of increasing wireless data capacity and competition, but the available data has shown overwhelming interference, and LightSquared should not be allowed to launch in the spectrum adjacent to GPS."
King says the GPS interference is so widespread and far-reaching—affecting everything from smart bombs and the defense industry to the “average backwoods fisherman trying to find his way home”—that the FCC is unlikely to greenlight LightSquared’s proposed network as currently planned.
In recent years, the FCC has taken a hands-off approach to the issue of spectrum interference, largely because it hasn’t posed a significant problem until now, says King.
A joint industry report is due to the FCC on June 15th, when the FCC will begin a public comment period before making its final decision.