LightSquared plans "incompatible with aviation GPS": RTCA

RTCA President Margaret Jenny has presented oral testimony before the US Congress outlining the consensus findings of RTCA Special Committee 159´s (SC-159) study of the impact of the proposed LightSquared terrestrial wireless broadband network on GPS receivers onboard aircraft.
RTCA is a private, not-for-profit US corporation that develops consensus-based recommendations regarding communications, navigation, surveillance, and air traffic management (CNS/ATM) system issues.
It functions as a Federal Advisory Committee and its recommendations are used by the Federal Aviation Administration (FAA) as the basis for policy, programme, and regulatory decisions and by the private sector as the basis for development, investment and other business decisions.
“The RTCA study concludes that all three spectrum deployment phases described for the planned LightSquared terrestrial network are incompatible with the current aviation use of GPS,” Jenny explained.
“However, use of a single 5 MHz lower channel could allow the LightSquared system to co-exist with aviation use of GPS, and further study is recommended to verify the conclusions for a LightSquared deployment scenario that involves only the lower 10 MHz channel.”
The hearing, “GPS Reliability: A Review of Aviation Industry Performance, Safety Issues, and Avoiding Potential New and Costly Government Burdens” was held by the US House of Representatives Committee On Transportation and Infrastructure, Subcommittees on Aviation, and Coast Guard and Maritime Transportation.
Two House Transportation and Infrastructure subcommittees conducted oversight hearings on June 23 to discuss potential impacts on US aviation safety in light of pending government action that may affect GPS reliability.
The Federal Communications Commission (FCC) is considering an application to build out nationwide broadband Internet infrastructure, which would allow high-power Internet broadcast stations to be built across the country broadcasting on the spectrum neighboring the low-powered GPS signal, according to a June 10 government advisory.
High-powered broadband signals will overpower and disable critical GPS navigation and timing function, industry stakeholders who use GPS have warned.
Since the current aviation operations, as well as the FAA’s Next Generation Air Transportation System (NextGen), are dependent on GPS, some in the aviation community have pointed to potential negative impacts GPS interference may have on aviation safety, air traffic control modernisation, and job creation within the aviation industry. Initial government testing has validated some of these interference concerns, including interface with civil, military and US Coast Guard receivers.
The complete written submission of the RTCA statement is available at