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LightSquared deals with continued GPS interference  (Source:
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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10% ???
By name99 on 12/12/2011 1:30:37 PM , Rating: 3
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.

WTF? "only" 10% --- and that their optimistic scenario? Just how well do they think this is going to fly, that 10% of users are going to have their GPS stop working? How long did they expect it would be until we heard some story of a rescue operation or police operation that was delayed because their GPS didn't work, or military training exercise that went wrong?

The whole plan seems to have been conceived by idiots if they thought "only" 10% was acceptable.

RE: 10% ???
By Mitch101 on 12/12/2011 1:54:28 PM , Rating: 2
At first I saw Government Survey and got worried who but then Im glad to see the DOD, FAA, Garmin, FedEx, UPS, and OnStar were involved with that survey because LightSquared is spinning a kind of different story.
LightSquared has come out with its most concrete claims so far that its LTE network will not interfere with GPS services across the US. The start-up says an Alcatel-Lucent laboratory has carried out extensive tests on devices from three GPS vendors, whose preliminary results demonstrate that those devices are not disrupted by the LTE signals in nearby mobile satellite spectrum.

But then they are pretty much admitting guilt in this part of their statement:
LightSquared has proposed various remedies to the GPS issue, including restricting its services to the area of its spectrum which is furthest from the navigation service bands.

Ummm nothing more to say after that.

RE: 10% ???
By Motoman on 12/12/2011 2:00:08 PM , Rating: 2
...those two statements would, in fact, seem to contradict one another...

RE: 10% ???
By DT_Reader on 12/12/2011 2:50:44 PM , Rating: 2
What you're missing is that if the GPS folks had played by the rules and used proper filtering in the first place, this wouldn't be an issue. But when GPS began there was no LightSquared, so they cheaped out on the filters since there was nothing there to filter. Now a legitimate user of the neighboring spectrum wants to open shop and they are screaming "No!" solely on the basis of squatter's rights.

Nothing that LightSquared is doing is wrong, it's the GPS receiver makers who made the mistake, and they want LightSquared to pay for it. We taxpayers pay for it, too, because now that's spectrum the FCC can't sell to anyone, and you can bet the GPS people (the squatters) aren't going to pay for it either.

I say let LightSquared use their spectrum and if anyone has problems they can take it up with the maker of their GPS unit. These tests are meaningless unless they were conducted with GPS receivers that meet their (well known but ignored) filtering requirements.

RE: 10% ???
By JediJeb on 12/12/2011 3:10:43 PM , Rating: 2
Not to say the GPS Unit makers are not wrong in how they designed their units, but if they did design them properly would we still be giving GPS receivers as stocking stuffers or would they still be considered as high end gadgets only companies and rich people played with?

RE: 10% ???
By semiconshawn on 12/12/11, Rating: -1
RE: 10% ???
By Solandri on 12/12/2011 5:35:44 PM , Rating: 4
What you're missing is that if the GPS folks had played by the rules and used proper filtering in the first place, this wouldn't be an issue. But when GPS began there was no LightSquared, so they cheaped out on the filters since there was nothing there to filter.

No. The spectrum owned by LightSquared was originally used by Inmarsat to communicate with satellites. The satellite signals were about as weak as GPS signals. And the ground station broadcasts to satellites were highly directional. Other bands in that spectrum were reserved for amateur communications to satellites, so again, a similar type of use.

GPS receivers were designed with filters adequate to remove this low level of noise at those frequencies. In 2004 LightSquared got permission from the FCC to repurpose the spectrum for land-based cellular data services. Essentially, the FCC gave them permission to blast away at those frequencies at energy levels thousands of times higher than originally allowed, omnidirectionally instead of pointed straight up. This is what's causing the interference with GPS. The GPS receivers at the time were designed to filter out the FCC-mandated maximum level of noise from those adjacent frequencies. It's the FCC (at LightSquared's behest) which raised those maximums far beyond levels where existing equipment can cope.

Also, many electrical engineers in the industry have come forward to state unequivocally that the frequencies are so close and LightSquared's proposed broadcast signal strengths so high that it is literally impossible to filter it out so that there is no degradation of GPS service. The units which fared well in the test are probably bigger units with better antennas and more power for electronic filtering and signal processing. If LightSquared's project goes live, you can probably kiss the GPS in your phone goodbye.

RE: 10% ???
By knutjb on 12/13/2011 1:01:34 AM , Rating: 2
The units which fared well in the test are probably bigger units with better antennas and more power for electronic filtering and signal processing. If LightSquared's project goes live, you can probably kiss the GPS in your phone goodbye.
What about those in cars, boats, or worse yet aircraft. Changing these kind of standards in such a rushed manner is dubious at best but prevent drilling for oil or running a pipeline without an extra decade just to make sure it's safe. Hmm....

RE: 10% ???
By Motoman on 12/12/2011 1:54:50 PM , Rating: 1
...within 100 meters of one of their base stations.

So, yeah, it's probably not the greatest goal in the world...but not quite as much of a cataclysm as it would sound without the "100 meters" bit.

RE: 10% ???
By dgingerich on 12/12/2011 2:18:08 PM , Rating: 2
100m = 328ft

Even if the towers are 100ft tall (most cell phone towers are around 30-50ft up) it would put out interference about a block away.

Imagine coming up to an intersection, waiting to have your gps tell you which turn to take, and all of a sudden it loses the GPS signal. You have no idea which way to turn.

Definite interference at 100m means intermittent interference out to three times that. You would be a couple blocks away and all of a sudden have your gps device (or smartphone, or tablet) lose signal and quit giving you directions.

Considering they claimed they'd use a low power mode to prevent the interference, then put out equipment that defaulted to high power mode, I wouldn't trust anything they said. They just want to make money and don't care who they interfere with in the process.

RE: 10% ???
By DT_Reader on 12/12/11, Rating: -1
RE: 10% ???
By dgingerich on 12/12/2011 4:12:30 PM , Rating: 2
I can apply that to the GPS people who are effectively squatting on LightSquared's spectrum. They just want to steal this spectrum (because stealing the spectrum is cheaper than replacing all those GPS units with ones that work properly) and don't care who they steal it from in the process.

Um, yeah, we'll just tell the US Air Force that, since they are the ones who set up the concept, designs, satellites, and initial devices.

RE: 10% ???
By Bad-Karma on 12/12/2011 10:42:34 PM , Rating: 1
You sir, are squandering the O2 supply.......

RE: 10% ???
By Motoman on 12/12/2011 3:48:37 PM , Rating: 1
Acknowledged. It seemed like the OP was under the impression that it would knock out 10% of all GPS devices across the board. Which would really be a catastrophe...only affecting 10% of GPS devices within 100m is simply a much smaller catastrophe ;)

RE: 10% ???
By fic2 on 12/12/2011 6:51:44 PM , Rating: 2
That isn't what happens with a TomTom GPS. Just used one in New Zealand during vacation. Every time the TomTom would loose GPS lock (frequently) it would just shout out "Turn right here". Usually meaning either off the cliff or into the side of the mountain. I don't know why it was trying to commit suicide, but I would never buy a TomTom. Not to mention even though it had "updated" maps from this year it still didn't know about roads that had been there for 5+ years.

RE: 10% ???
By 0ldman on 12/14/2011 10:55:05 AM , Rating: 2
Generally, at least in the US, if the maps are wrong it is because the government has poor mapping. The rural area I live in is completely wrong. Most county roads are completely backwards from the actual layout and there are several that are off by miles as to where the road actually is.

Whoever is responsible for mapping our area (USGS?) apparently is "close enough", which makes most GPS units useless here.

Comes down to ignorance again.

RE: 10% ???
By Zoomer on 12/12/2011 3:55:49 PM , Rating: 2
IMO, this is totally not lightsquared problem. They got a license to the frequency band at specified power levels, and should be able to use said license. It's not their problem if some one else screwed up before.

RE: 10% ???
By semiconshawn on 12/12/2011 4:48:12 PM , Rating: 2
This is totally a LS problem. Makes no difference who is wrong or to blame. LS is the one with the problem they cant deploy. That is the problem. Nobody else is having any problems.

RE: 10% ???
By DPigs on 12/12/2011 5:40:25 PM , Rating: 2
I have recently acquired mo' money. Can I expect any net change in my number of problems?

RE: 10% ???
By MrTeal on 12/12/2011 5:54:36 PM , Rating: 2
No. Any change in the number of problems is offset by the fact that there are men who, for a certain sum, can make problems "disappear".

RE: 10% ???
By DockScience on 12/12/2011 6:44:51 PM , Rating: 2
This is TOTALLY a LightSquared problem... with some enabling help from the Obama admin (who get lots of donations from the Lightsquared investors)

Lightsquared bought spectrum for the EXPRESS and LIMITED use from satellites.

They then asked their admin cronies to change the spectrum license to allow the same power (15KW) from thousands of ground stations that would have been allowed from satellites. Thus the interference issues.

RE: 10% ???
By bigdog1984 on 12/12/2011 7:51:22 PM , Rating: 3
Why is it that people have no concept of time when posting about political problems? Lightsquared licensed the spectrum in 2004. How does the Obama administration have anything to do with enabling their blunder?

RE: 10% ???
By mcnabney on 12/12/2011 8:19:40 PM , Rating: 3
Didn't you get the memo?

Everything that has ever gone wrong in history is Obama and his time machine's fault.

RE: 10% ???
By Dorkyman on 12/12/2011 10:06:12 PM , Rating: 2
...when in fact we all know it was Bush's fault.

Messiah is a brilliant man, Bush an idiot. Why, Bush went to Yale and got some C's, while Messiah went to Hahvahd and got some...wait... Oh, yeah. He refuses to release his grades. Wow, he must be REALLY smart.

RE: 10% ???
By Black1969ta on 12/12/2011 10:55:21 PM , Rating: 2
Stupid Obama, if he hadn't knocked that Apple off the tree Women wouldn't still be fighting gravity! And why did Newton have to be sitting under that tree anyway!

RE: 10% ???
By hartleyb on 12/13/2011 11:13:06 AM , Rating: 2
The problem is that while you are correct that the license was issued 2004, you should also know it was issued for testing not operation, and the Obama administration tried to get the Airforce to coverup the GPS issue by suppressing testimony.

I say let LS and the administration have their way, and the first time a major airliner crashes becuase of positional error let the people sue LS and Obama.

RE: 10% ???
By Just Tom on 12/19/2011 8:18:53 PM , Rating: 2
The original license was modified to allow for use of terrestrial only stations rather than a combination of satellite and terrestrial stations in January of '11. This waiver, whether wise or unwise, was made by the FCC which is controlled by Obama appointees. If it is an unwise move then Obama should indeed bear the blame; if it is a good move, leading to increased competition and minimal impact on GPS function, then Obama should get the credit.

Not everything is Obama's fault, or his credit, but some things indeed are.

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