"LightSquared is a company that plans to provide a wholesale, nationwide 4G-LTE wireless broadband
network integrated with satellite
coverage. The plan is to cover all parts
of the U.S. with wireless service
, with the intent that even remote
rural areas would have 4G services via satellite
when its standard terrestrial service
would not reach customers.
LightSquared would combine existing mobile satellite communications
services with a ground-based wireless communications
network that uses the same radio
spectrum as the satellites. Last January, the Federal Communications Commission gave LightSquared conditional approval to build out its ground-based wireless network.
The controversy amid the GPS community arose when it became aware that base stations of the LightSquared network would transmit signals in a radio band immediately adjacent to the GPS frequencies. The GPS community is concerned because testing has shown that LightSquared's ground-based transmissions overpower the relatively weak GPS signal from space.
Although LightSquared will operate in its own radio band, that band is so close to the GPS signals that most GPS devices pick up the stronger LightSquared signal and become overloaded or jammed. That would keep farmers, in particular, from using finely tuned Real Time Kinematic systems for precision planting.
The worst-case scenario, the coalition posits, as described in a statement: "LightSquared's plans to build up to 40,000 ground stations transmitting radio signals one billion times more powerful than GPS signals as received on earth could mean 40,000 'dead spots'—each miles in diameter—disrupting the vitally important services GPS provides."
There is also concern that the FCC may approve a technical solution to the problem that requires millions of existing GPS users to upgrade or replace their devices.
This is according to a report from the National Executive Committee for Space-Based Positioning, Navigation, and Timing, a U.S. government
organization established by presidential directive to advise and coordinate federal departments and agencies on matters concerning the GPS and related systems."
Quoted from a recent press release.