LightSquared Proposes Solution to GPS Interference

LightSquared has outlined a solution to the problem of interference with Global Positioning System (GPS) receivers. This solution will permit LightSquared to proceed with its business plan.

Early test results indicated that one of LightSquared’s 10MHz blocks of frequencies poses interference to many GPS receivers. This block happens to be the specific set of frequencies that LightSquared planned to use for the initial launch of its nationwide wireless broadband network.

Based on those same early test results, LightSquared determined that another 10MHz block of the spectrum did not create such an interference risk. This block is lower on the spectrum band and located further away from the GPS frequencies, greatly reducing the risk for interference.

According to LightSquared, test results show this lower block of frequencies is largely free of interference issues with the exception of a limited number of high precision GPS receivers that are specifically designed to rely on LightSquared’s spectrum.

In its original plan, LightSquared planned to move into this other frequency block as its business grew over the next two to three years.? ?After assessing this information, LightSquared developed an alternative deployment plan focused on the lower block of spectrum to launch its nationwide wireless broadband service. It also entered negotiations with Inmarsat, the satellite company that controls the alternative block of spectrum in the L Band, to accelerate the schedule for LightSquared to begin using the frequencies.

LightSquared recently reached an agreement with Inmarsat that will allow the rollout of its wireless network in a timeframe that keeps to the original business plan and is in accordance with regulatory requirements. As part of this revised plan, LightSquared will modify its FCC license to reduce the maximum authorized power of its base-station transmitters by over 50 percent. This action will limit LightSquared to the power it was authorized to use in 2005, which will provide additional protection to GPS.

For a comprehensive look at LightSquared, see Communications Technology’s upcoming July/August magazine.