greentips

LightSquared's proposal will disrupt GPS based air navigation and 500 million GPS units used by the military, aviation, civilians, mariners, high precision land surveyors, agricultural applications, EMS, ETC.

From Washington Post

From Cnet

"We want to see the complete report"..."However, the executive summary confirms what we believe, that LightSquared's terrestrial-based system interferes with aviation GPS, which is a major public safety issue."

- Bobby Sturgell, a former acting FAA administrator commenting on report given to FAA
The Washington Post, High-tech problems reach a higher plane - June 6, 2011


Recent testing on a proposal by LightSquared Communications for a new 4GTE network using bandwidth immediately adjacent to the present GPS satellite band has the potential to disrupt air navigation in and about major airports.

This is especially notable as the FAA is transitioning to GPS based NEXTGEN air traffic control over the next 9 years.

LightSquared fast tracked a request for a waiver to use L-band satellite frequencies adjacent to GPS satellite frequencies for a high powered terrestrial network late last year on an accelerated basis, and the FCC, without an engineering analysis issued a waiver last January.

Tests, which LightSquared ran at 1/2 their intended final transmitter power caused disruption of GPS signals at 5000 feet for over 20 miles from their transmitter. They delayed a joint report for two weeks to the FCC and then proposed to continue the project, slightly altered.

bocastephen

I'm fairly confident Lightsquared is DOA unless they are assigned different frequencies.

I read the article and a report about this a few weeks ago, and I cannot possibly conceive of their plan seeing the light of day (pardon the pun) if there is even the slightest chance of interference - and everyone from Garmin to the Pentagon is going to be all over this.

I do believe quite a few people at the FCC need to clean out their desks for being so stupid.

Global_Hi_Flyer

Having personally seen some other stuff the FCC has done, mostly because of "power" battles between them and other agencies, I am not the least bit surprised on how this went down.

They tried an end-run around the FAA over phase-out of 121.5 ELTs not too long ago, and at one time they floated a proposal to require filters be installed on aviation NAV receivers to eliminate interference from FM broadcast stations. Even though the agency's role is supposed to be electromagnetic compatibility, that's sometimes ignored when the frequencies that may be affected are either civil government frequencies or things of lower political value.

I agree with your original assessment, however, that Lightspeed is dead until a resolution can be found, and the resolution will likely be a different frequency band. Wonder who they'll take it from?

greentips

Maybe not. Lightsquared has persisted and issued a report to the FCC admitting to widespread and massive interference with GPS signals, but placing the blame on GPS receivers and suggesting that the cause was not their overpowered terrestrial signals, but poorly designed GPS receivers, suggesting that GPS manufacturers are responsible for fixing all GPS receivers. Lightsquared is well connected with the White House and since this all began in hurry up fashion last Thanksgiving, Lightsquared officials have made numerous visits to the White House.

The FCC has opened a comment period on making the Lightsquared waiver permanent, which can be found in Proceeding 11-109, and in its announcement, the FCC appears to be willing to grant the waiver, based on Lightsquared's filing.

Here are the limitations: Lightsquared can use the lowest 10 MHz of the L-band, and at only half power since this operation (which was not comprehensively tested) did not cause massive interference, but merely widespread interference, such as the approach equipment mandated for the airlines in NextGen air traffic control.

Lightsquared(in the RFC) has "indicated its willingness to (1) operate at lower power than permitted by its existing FCC authorization (2) agree to a "standstill" in the terrestrial use of its Upper 10 MHz frequencies immediately adjacent to the GPS band and (3) commence terrestrial commercial operations only on the lower 10 MHz portion of its spectrum and coordinate and share the cost of underwriting a workable solution to the small number of legacy precision measurement devices that may be at risk."

This does not sound to me like the proposal is DOA, but that the FCC intends to allow LightSquared to blast GPS off the air with its monster signals in an adjacent band.

I urge all who use GPS or fly in any airplane to file comments on the FCC website opposing this stupid decision by the FCC and its apparent empathy for Lightsquared's ill fated proposal. This should have been killed aborning, let alone have reached the testing stage. The testing stage demonstrations should have killed it, and yet it lives on. Comments can be submitted to the FCC at Proceeding 11-109 using the submit filing link.

jbfield

I wasn't sure whether to post this here, or over in the other post by greentips, but seeing as this has the most recent discussion on the topic, I'm putting it here:
LightSquared denied broadband licence