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LightSquared deals with continued GPS interference  (Source: engadget.com)
U.S. officials say no additional testing is needed to prove the existence of harmful interference

A recent government study found that the LightSquared Inc. wireless service interrupted 75 percent of global-positioning system (GPS) receivers.

LightSquared Inc. is a company looking to offer a wholesale 4G LTE wireless broadband communications network with satellite coverage in the United States. It was founded by Philip Falcone and has had interference issues for years now. Just this year alone, interference concerns were raised by the National Telecommunications and Information Administration (NTIA), USAF Space Command, and the U.S. GPS Industry Council.

Now, a test conducted by the U.S. government has shown that 69 of 92 (75 percent) of receivers experienced "harmful interference" at the equivalent of 100 meters from a LightSquared base station. It was deemed that millions of GPS units were incompatible with the LightSquared service, and it could affect cars, planes, boats and tractors.

The test was performed from October 31 to November 4 for the National Space-Based Positioning, Navigation and Timing (PNT) Systems Engineering Forum, which advises policy makers about GPS issues. The Department of Defense and the Federal Aviation Administration took part in the testing, as well as companies like Garmin Ltd., Trimble Navigation Ltd., Deere & Co., and General Motor Co.'s OnStar unit.

"LightSquared signals caused harmful interference to majority of GPS receivers tested," said U.S. officials in a draft prepared for the review of the LightSquared proposal. "No additional testing is required to confirm harmful interference exists."

LightSquared has proposed that it operate at a reduced power than the levels used during the testing. With low power usage, LightSquared believes its services would only affect 10 percent of devices.

Sources: Business Week, SlashGear



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RE: Commi plot to knock out GPS!
By Fritzr on 12/12/2011 10:36:23 PM , Rating: 2
A similar fence was implemented by allowing directional broadcast to satellites in orbit & low power broadcast to Earth based receivers. In that application, at the power levels allowed, the sideband noise was being filtered out by the GPS equipment. Unfortunately for Lightspeed, the FCC did not eliminate the sideband noise when they changed the permitted usage. Physics tends to trump bribes no matter what the lobbyists may try to tell you.

Increased broadcast power==increased sideband noise. Existing GPS equipment was designed to ignore the legally allowed noise from neighboring bands. The FCC now needs to modify the GPS license to increase the amount of noise they are required to tolerate or disallow this version of 4G cellphone service on these specific frequencies.


RE: Commi plot to knock out GPS!
By lothar98 on 12/13/2011 3:43:25 AM , Rating: 2
Thank you


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