Bruce Buls
Bruce Buls
The battle between makers and users of GPS equipment and a proposed wireless broadband system has heated up. The controversy stems from a conditional waiver granted by the Federal Communication Commission in January to LightSquared, a privately held company, for the terrestrial use of the mobile satellite spectrum (MMS) immediately adjacent to the frequency band used by GPS receivers.
LightSquared wants to establish a network of 40,000 ground stations to broadcast extremely powerful broadband wireless signals that could severely disrupt GPS signals, according to the Coalition to Save Our GPS, which represents a wide variety of industries and companies. In a statement on its website, the coalition states: “LightSquared plans to transmit ground-based radio signals that would be one billion or more times more powerful as received on earth than GPS’s low-powered satellite-based signals, potentially causing severe interference impacting millions of GPS receivers — including those used by the federal agencies, state and local governments, first responders, airlines, mariners, civil engineering, construction and surveying, agriculture, and everyday consumers in their cars and on handheld devices.”
A Technical Working Group including representatives from LightSquared and GPS manufacturers ran a series of tests with more than 100 GPS devices over a five-month period following the FCC’s action in January. The TWG’s report was filed with the FCC on June 30. The official comment period ended Aug. 15.
According to the coalition, “TWG’s test results conclusively demonstrate that LightSquared’s initial proposal would cause harmful interference to all types of GPS receivers tested.”
The Coalition also disputed LightSquared’s claims that using only the lower portion of its proposed MMS band and the use of filters on GPS equipment would solve any potential interference problems.
Workboat.com