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LightSquared Says GPS Tests Were Rigged

Soulskill posted more than 2 years ago | from the apparently-you-can-stop-the-signal dept.

Wireless Networking 186

itwbennett writes "Would-be cellular carrier LightSquared claims that the company's LTE network was set up to fail in GPS interference tests. 'Makers of GPS (Global Positioning System) equipment put old and incomplete GPS receivers in the test so the results would show interference, under the cover of non-disclosure agreements that prevented the public and third parties from analyzing the process,' LightSquared executives said on a conference call with reporters Wednesday morning."

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186 comments

Really? (5, Insightful)

Zeromous (668365) | more than 2 years ago | (#38748042)

>old and incomplete GPS receivers

I'm not an expert in the deployment of GPS, but is this not what we would consider a real-world test? Why should they be set up to pass the test, by only testing the latest deployments of GPS?

Don't you test, in order to understand previous unknowns or to flesh out previously unforeseen scenarios?

Re:Really? (4, Insightful)

ZaMoose (24734) | more than 2 years ago | (#38748064)

They're desperate and in spaghetti-against-the-wall territory, to be honest.

Re:Really? (4, Insightful)

Anonymous Coward | more than 2 years ago | (#38748100)

And thank god for that. Forget the millions of drivers for whom GPS is a convenience; LightSquared would spell an end to the major advanced in aviation navigation systems and the accompanying time- and fuel-efficiency gains that have come with it. Check out Canadaian airline WestJet's use of so-called "RNAV" approaches into airports; their use of GPS in those systems saves them millions of dollars in fuel every year, plus gives them and their passengers the benefit of faster trips. No more bouncing around through the 3000 or so VHF Omnidirectional Radio beacons that dot North America.

Re:Really? (-1, Offtopic)

jonbryce (703250) | more than 2 years ago | (#38748136)

And forget the billions of ATM users for whom GPS is essential, even if they don't realise they are using it. ATMs use GPS to get an accurate time signal as knowing exactly what the time is is essential to its operation.

Re:Really? (-1)

Thantik (1207112) | more than 2 years ago | (#38748310)

LightSquared doesn't interfere with properly engineered devices. It interferes with all the cheaply made, poorly engineered GPS units that operate outside of GPS frequencies and _into_ the LightSquared spectrum.

Re:Really? (2, Informative)

Anonymous Coward | more than 2 years ago | (#38748384)

That is completely false. Just FALSE.

Re:Really? (1)

Anonymous Coward | more than 2 years ago | (#38748712)

Mind providing an explanation or evidence to back up your claims? Both of you?

Re:Really? (5, Informative)

Anonymous Coward | more than 2 years ago | (#38748822)

It comes down to the fact that there is currently no way to reliably demodulate and decode a signal sitting down at -130 dBm (roughly the strength of a GPS signal in some areas) while you're experiencing interference trillions of time stronger as a result of sidebands from a base station.

It's a fundamental concept that all time limited signals mathematically have infinite bandwidth. However, the FCC defines bandwidth by the region where 99.99% of the power resides. Let's say you have a 150W base station. That would mean up to 1.5e-2W is outside the targetted frequency band. Now lets assume about .001% of that power resides on top of the band where your signal of interest is coming in. That would mean 1.5e-7W is on top of your signal of interest or (-38dBm). For reference, the signal at -130dBm is roughly equivalent to 1e-16W.

The numbers above are general estimates used for illustration, but lets say that only .0000001% of the base stations power falls into the band where your signal of interest resides. That interfering signal is still sitting at -68dBm while your GPS signal is sitting at -130dBm.

Re:Really? (0, Interesting)

Anonymous Coward | more than 2 years ago | (#38748722)

No, completely true. The LightSquared broadcast signal is over 20 MHz away, which is a huge guard band. LightSquared does not put RF energy into GPS frequencies, but rather the GPS receiver front end gathers energy. As evidence, you can refer to the fact that 0% of cellular handsets experience interference. Because these devices generate RF, they have proper GPS front end filtering and do not experience interference. So you can pick bones, but this statement falls well short of completely FALSE.

Re:Really? (1)

mjr167 (2477430) | more than 2 years ago | (#38749530)

That's not what my Verizon network specs tell me... There is an entire table of in-band and out-of-band signals the device has to contend with.

Re:Really? (5, Insightful)

PhxBlue (562201) | more than 2 years ago | (#38748474)

Don't be an idiot. GPS receivers don't broadcast -- that's up to the satellites, which transmit timing and location data on two separate bands (three for newer GPS-IIR and IIF satellites).

Re:Really? (1)

Anonymous Coward | more than 2 years ago | (#38748618)

He didn't say they broadcast. He said operate. In this case receiving. For DGPS they have publicly stated that they make use of GPS signalling outside of the defined mask to improve performance. For commercial GPS, they just don't filter beyond the mask as it's marginally more expensive to make the device reject RF outside of the mask and this has been a traditionally quiet RF neighborhood.

Re:Really? (5, Informative)

RockClimbingFool (692426) | more than 2 years ago | (#38748588)

Troll much?

GPS receivers are designed to filter out the neighboring frequencies, when the neighboring frequency sources are satellites transmitting at power levels comparable to GPS satellites.

That is how that portion of the spectrum was designed and allocated. LightSquared is trying to use terrestrial transmitters at these frequencies. GPS receivers were never designed to filter out their signal from neighboring sources that are literally a billion times more powerful.

You don't know anything about RF transmission and why there have always been transmission power restrictions on the allocated spectrum. The spectrum allocation was specifically designed to prevent this exact situation from occurring.

Re:Really? (1)

Anrego (830717) | more than 2 years ago | (#38748606)

I can actually see LightSquared perspective. In an ideal world, the solution would be to fix all those devices that are affected by things they shouldn't be affected by. Just not likely to happen.

At the same time, they are using something slotted for satellite communication, so it's somewhat reasonable for GPS devices to not have been designed to filter something they never expected to be subjected to.

Re:Really? (1)

russotto (537200) | more than 2 years ago | (#38749450)

I can actually see LightSquared perspective. In an ideal world, the solution would be to fix all those devices that are affected by things they shouldn't be affected by. Just not likely to happen.

Unfortunately, a "brick wall" filter with very high roll-off and attenuation turns out to be large and expensive.

Re:Really? (1)

cdrguru (88047) | more than 2 years ago | (#38748690)

Yeah, right. Like it doesn't interfere with $1500+ GPS devices but totally messes with the ones people actually buy.

Re:Really? (3, Informative)

spire3661 (1038968) | more than 2 years ago | (#38749412)

Lightguard's allocated spectrum is supposed to be for SATELLITE use, they want to use it on the ground which was not included as part of their licensing agreement.

Re:Really? (5, Informative)

tlhIngan (30335) | more than 2 years ago | (#38749760)

And thank god for that. Forget the millions of drivers for whom GPS is a convenience; LightSquared would spell an end to the major advanced in aviation navigation systems and the accompanying time- and fuel-efficiency gains that have come with it. Check out Canadaian airline WestJet's use of so-called "RNAV" approaches into airports; their use of GPS in those systems saves them millions of dollars in fuel every year, plus gives them and their passengers the benefit of faster trips. No more bouncing around through the 3000 or so VHF Omnidirectional Radio beacons that dot North America.

Actually, you mean RNP (Required Navigation Performance) which are a set of approaches that are more efficient, but require that the plane have onboard a minimum set of equipment. And one of this is dual RAIM [wikipedia.org] -locked GPS units.

A RAIM-locked GPS is a receiver that can see more than the 4 minimum GPS satellites - and all aviation GPSes have utilities that can take a location (destination) and time and calculate whether or not a RAIM lock is achievable (it depends heavily on the satellite configuration at that point in time).

Primary purpose of RAIM is to help the GPS decide if a satellite is "out of whack", which is essential if you need to figure out your position accurately.

RNAV is slightly different - it requires a flight management system that basically generates a GPS-like path by taking in multiple navigation sources like VORs and NDBs and calculating a virtual track based on your position relative to those navaids. So you're not flying navaid to navaid, you're flying a course through but using the navaids to cross-reference your position continually.

These days, a combination of RNAV, INS (Inertial navigation system) and GPS are used altogether to get very accurate positioning required for RNP. (RNP dictates the minimum performance your navigation equipment can have - you can always use better equipment to fly the RNP approaches more precisely).

Re:Really? (0, Insightful)

Anonymous Coward | more than 2 years ago | (#38748112)

They are just completely fucked, and I actually feel kind of bad for them. I mean, they theoretically "own" this nice slice of wireless spectrum, which they bought at considerable expense, and they want to do something pretty cool with it, but they're not allowed to because some other industry has been illegally bleeding into their spectrum for years and now it's too late to fix it.

Re:Really? (5, Informative)

jonbryce (703250) | more than 2 years ago | (#38748160)

They own a slice of wireless spectrum which is supposed to be used for satellite communication, and they want to use it for ground based cellphone communication.

Re:Really? (1)

Anonymous Coward | more than 2 years ago | (#38748188)

As far as I know they only own it for satellite to earth communication unless they can prove there is no interference when using it with cell towers so it is not completely fair to blame GPS companies for failing to filter something that no one expected.

Re:Really? (5, Informative)

holmstar (1388267) | more than 2 years ago | (#38748202)

No, they bought a band that is designated for low power satellite communication and are trying to get the designation changed to allow high power terrestrial communication. They aren't an innocent bystander in this mess.

Re:Really? (-1)

shentino (1139071) | more than 2 years ago | (#38748256)

So either

1. Prosecute everyone bleeding into it without an FCC license
2. Demand a refund for the slice of spectrum

Re:Really? (4, Informative)

Anrego (830717) | more than 2 years ago | (#38748680)

As I understand it, it's not so much bleeding as lack of filtering. Lack of filtering because the chunk of spectrum was slotted for low powered satellite to earch communication, not the high power they want to use it for.

They are trying to get permission to use it for a purpose it was never intended for, as part of that they have to prove that the change won't interfere with anything.. and of course.. it is interfering with stuff.

I really do feel for them.. it's a pretty shitty deal.. but it's not like they bought a chunk of land to build something and can't get rid of the squatters. It's like they bought a chunk of land in a residential area and are trying to put up a skyscraper.

Re:Really? (2)

Dishevel (1105119) | more than 2 years ago | (#38749018)

Not to worry. They will get it through.
They have a friend in a very high place.
It matters not what it will wreck only how much campaign cash it will generate.

Re:Really? (0)

Anonymous Coward | more than 2 years ago | (#38749078)

As I understand it, it's not so much bleeding as lack of filtering. Lack of filtering because the chunk of spectrum was slotted for low powered satellite to earch communication, not the high power they want to use it for.

You've almost got it right. It is a bleeding problem in the sense that the terrestrial base stations would be bleeding power into the band on top of where the GPS signal resides. This then becomes more than just a problem with the front end filtering. At this point you're hoping that the channel is coded strongly enough to be able to decode the information in the signal reliably.

With the amount of inteference a terrestial base station can produce with respect to GPS signal strengths, this sort of task becomes next to impossible with current techniques (that I know of).

Re:Really? (2)

spire3661 (1038968) | more than 2 years ago | (#38749468)

Why do you feel for them? They bought something from the People and then turn around and say 'We know you said we are only supposed to use it this way, but we are gonna use it this way, problem?" They brought this on themselves.

Re:Really? (5, Insightful)

rahvin112 (446269) | more than 2 years ago | (#38749472)

And they got a steal on the residential parcel and if they can get it rezoned for the skyscraper it's worth 100X what they paid for it. This was nothing more than a gamble to try to get spectrum reallocated to ground prices. They paid almost nothing for spectrum that if it was ground based would be worth almost 6 billion (based on the last auction). The entire reason the spectrum is cheaper is that it costs $2billion minimum to put a satellite in orbit to use it.

Lightsquared is neither innocent nor deserving of sympathy. They were told multiple times the waiver they were given was for testing. It would be foolish of the FCC to not allow them a chance to prove they have developed filtering technology capable of working around the physics. When their testing showed their signal would destroy high precision GPS they had the gall to suggest that the billions of installed GPS receivers have to be replaced that's when they lost all sympathy from me. I have a feeling they've not only known from the begining that this would never work but that they thought they had the political muscle to move it through. Not only that but I don't believe they ever really intended to build a network, but their real intention was to get the spectrum usage switched then sell it 10X what they paid for it.

Re:Really? (1)

Anrego (830717) | more than 2 years ago | (#38749586)

Hmm, I was unaware of all that.

I guess yeah, I don't feel much sympathy for them any more. If that's actually how it went down, they've got what's coming to them.

Re:Really? (-1)

Defenestrar (1773808) | more than 2 years ago | (#38748356)

If this is indeed the case, then GPS should be liable (the manufacturers of said receivers and transmitters) with a fair amount of that burden coming back on the tax payers. If Joe down the street sold me something, and then came back and told me I couldn't use it because it was essential to something else he still owns, Joe should offer to buy it back; but with no obligation for me to sell, Joe may simply be out of luck. If Uncle Sam sells me something...

Now the other way to see this story is: Joe sells me something, I find out that using what Joe sold me (through a previous design fault of Joe's) will endanger lives, cost third parties millions, and otherwise wreck havoc if I use it for my activities which may in the future save lives and earn third parties millions of dollars. So if Joe refuses to own up and fix the problem (or even buy the item back) - we have an ethical dilemma. So if Uncle Sam...

Usually when it comes to Uncle Sam and the "public good" some groups can get royally er republically screwed in a way that can give them a real trail of tears. Even if courts land on their side, enforcement is another issue.

Re:Really? (5, Informative)

Dishevel (1105119) | more than 2 years ago | (#38749108)

If Joe sells you an off road vehicle then you try to get it licensed to be street legal do not get pissed at Joe because it will not be allowed on the road.
Radios are very complicated. Till I got my current job I had no idea how little I knew about them. Get education on the subject. They are attempting to use this spectrum in a way in which their current license specifically prohibits. Also it is prohibited for a very good reason. They are trying to change their license and it is that change that is causing the problems.

Re:Really? (0)

Anonymous Coward | more than 2 years ago | (#38748776)

Sorry, but you've got it backwards. GPS signals are not bleeding into the spectrum that they bought (or, if they are, it's not the problem that these tests found). The signals that they are broadcasting are bleeding into the GPS spectrum, and at least some older units are unable to correctly compensate for the interference. The test was supposed to prove that this didn't happen, so the FCC would give them permission to operate. Since it proved the opposite, obviously the test was flawed.

Re:Really? (1)

WaffleMonster (969671) | more than 2 years ago | (#38749432)

They are just completely fucked, and I actually feel kind of bad for them. I mean, they theoretically "own" this nice slice of wireless spectrum, which they bought at considerable expense, and they want to do something pretty cool with it, but they're not allowed to because some other industry has been illegally bleeding into their spectrum for years and now it's too late to fix it.

Here we go again... and again...and again. A grant to spectrum comes with fine print dictating how it can be used. You simply do not have the right to do whatever you want as long as it remains in-band..

Their existing allocation was provided under the ATC integrated services rule which explicitly prohibits proliferation of ground stations.

What they did was apply for an exemption to the rule they had purchased their spectrum under which has thus far not been granted due to interference concerns.

"considerable expense" is peanuts compared to what an AT&T or a verizon would pay at auction for the same bandwidth nationally. Why does LS deserve a loophole?

Re:Really? (0)

Anonymous Coward | more than 2 years ago | (#38748444)

I guess that's what happens when your engineers are idiots and use already-used frequencies.

Re:Really? (1)

greed (112493) | more than 2 years ago | (#38748142)

And how old is old? I know several people still using the black & white Garmin StreetPilot... you can't get map updates for it, it's that old--circa 1998.

My Zumo is pushing 5 years old; it does all I want, and updates are still available... though now I have to pick and choose what regions to load. So I'm not replacing it.

Serial loggers might be even older, as they have no processing except the satellite receiver, so there's no rush to update them. Any chartplotting is done by the computer they're attached to.

Re:Really? (5, Insightful)

CompMD (522020) | more than 2 years ago | (#38748318)

It is a real world test. LightSquared has this fantasy that people replace GPS hardware like they do cell phones every two years (or less). There are LOTS of GPS receivers out there that are 10+ years old, and they can't grasp the fact that THOSE WORK FINE.

Re:Really? (1)

Zeromous (668365) | more than 2 years ago | (#38749720)

This was my thought exactly. No one ever wants to talk legacy.

Re:Really? (3, Funny)

Lumpy (12016) | more than 2 years ago | (#38748378)

I am sure that the FCC will let them go if they state that they will buy everyone on the planet brand new top of the line GPS receivers to get around this issue.

I'll support them as long as they replace my 4 GPS's with $1500.00 each units. Heck I'll be generous and let them cheap out with Garmin Zumo 665's Those are only $780 each.

Re:Really? (0)

Anonymous Coward | more than 2 years ago | (#38749826)

Sure, no problem. They just need to donate to the right campaigns, then pick up a government subsidy of $10,000 per receiver.

Who is interfering with whom? (3, Informative)

Tokolosh (1256448) | more than 2 years ago | (#38748656)

Re:Who is interfering with whom? (1)

Mitsoid (837831) | more than 2 years ago | (#38749606)

From what I gather from that article.. Many GPS devices are "operating" outside their spectrum as well -- They scan frequencies just above and blow their spectrum to help 'filter' and find the signals they want... This means cell towers operating within their proper frequency would screw up GPS receivers that need that out-of-band data to help filter

Re:Really? (0)

Anonymous Coward | more than 2 years ago | (#38748782)

Also, using an initial terrestrial based concept and moving it to satellite based doesn't transfer well when the power and noise thresholds differ by several orders of magnitudes from the former.

If the FCC has any balls or brains, they won't give these clowns any extensions to get their shit together, even if they come up with a technical solution to the noise floor problem.

Re:Really? (1)

MDMurphy (208495) | more than 2 years ago | (#38749360)

Also, using an initial terrestrial based concept and moving it to satellite based doesn't transfer well when the power and noise thresholds differ by several orders of magnitudes from the former.

/quote>

That's a little backwards. It was an initial satellite based system (with terrestrial fill-in) and LightSquared desires to offer terrestrial only devices. Having terrestrial-only means there needs to be a greater number of towers ( or higher power towers ) to offer coverage.

The waiver issued a year ago was conditional. It was conditioned on not interfering

With the Laws of Physics Against Them (2)

turkeyfish (950384) | more than 2 years ago | (#38749248)

With the Laws of Physics Against Them, they have decided to turn to Public Relations a tried and true way to overcome conservation laws.

Fraud, sour grapes, or late complaint? (5, Insightful)

davidwr (791652) | more than 2 years ago | (#38748066)

If this is fraud on the GPS companies' part or the testing authority's part then there should be hell to pay.

If this is sour grapes then LightSquared just libeled the companies involved.

If, on the other hand, "old and incomplete equipment" tests were a required part of the test for good reason, then LightSquared is a bit late in its complaints - it should've made these complaints well before testing happened, and its current statement should've started off with "As we said before the tests were run, testing for old and incomplete equipment is not a valid test...."

Re:Fraud, sour grapes, or late complaint? (5, Informative)

LehiNephi (695428) | more than 2 years ago | (#38748154)

If you follow the link in the earlier story, 69 of the 92 GPS receivers had issues. That's either a lot of interference or a lot of older GPS units.

And even if it's old equipment, in my opinion it's still fair game, provided they're not all some obscure model that sold only a couple hundred units.

Re:Fraud, sour grapes, or late complaint? (1)

gstoddart (321705) | more than 2 years ago | (#38748990)

If you follow the link in the earlier story, 69 of the 92 GPS receivers had issues. That's either a lot of interference or a lot of older GPS units.

I've got a hand-held Magelan SporTrak I bought almost 10 years ago.

It's not something I'd use in my car, because it doesn't have street level maps. But, for hiking/mountain biking in areas where I'm on trails I don't know well, I still expect it to work.

If LightSquared is bitching that the test unfairly shows that older receivers have a problem, well, then they're now claiming that all of the older GPS units are somehow "wrong" and it is "unfair" to test their stuff against things which are already in service.

That to me sounds like a company saying it's not fair they be required that an old car can still drive on their roads and bridges. The GPS spec has been around for quite a while, and there is an expectation that the older devices should still work with it ... if their stuff breaks that, then I'd say they're the ones doing something wrong.

Re:Fraud, sour grapes, or late complaint? (0)

Mitsoid (837831) | more than 2 years ago | (#38749686)

There's some concern that many GPS units scan above and below their allowed frequency to help filter & find the signal they are looking for... Meaning 'cheap' GPS units are reading signals outside their allotted band as part of their filter to allow the devices to be cheaper..

So ASSUMING Lightsquared, operating 100% within their spectrum, and not interfering with GPS frequencies, could still interfere with GPS because the GPS Unit itself is using part of Lightsquared's spectrum for filtering purposes..

Deere Tractors has an issue with this because their tractors have $15,000 GPS Units that fall into this category, so instead of fixing all the farmer's tractors, they'd rather keep LS from operating through politics

Re:Fraud, sour grapes, or late complaint? (4, Insightful)

holmstar (1388267) | more than 2 years ago | (#38748162)

Of course there's a good reason. Do you really think every GPS device out there is nearly new? There are hundreds of thousands of older devices out there still in use. It would be wrong NOT to test in such a way as to assure that these currently functional devices, which people payed their hard earned money for, continue to work properly.

Re:Fraud, sour grapes, or late complaint? (2)

Lumpy (12016) | more than 2 years ago | (#38748418)

The autohelm navigation GPS in my boat is 12+ years old and works fine. IT actually steers the boat to keep it on course. Unless the morons at that company want to buy me a complete new Autohelm system to solve the issue.

Re:Fraud, sour grapes, or late complaint? (5, Informative)

Anonymous Coward | more than 2 years ago | (#38748460)

It doesn't matter what sort of equipment was used or what claims Lightsquared is making. It comes down to the simple fact that there is currently no way to reliably demodulate and decode a signal sitting down at -130 dBm while you're experiencing interference trillions of time stronger as a result of sidebands from a base station.

It's a fundamental concept that all time limited signals mathematically have infinite bandwidth. However, the FCC defines bandwidth by the region where 99.99% of the power resides. Let's say you have a 150W base station. That would mean up to 1.5e-2W is outside the targetted frequency band. Now lets assume about .001% of that power resides on top of the band where your signal of interest is coming in. That would mean 1.5e-7W is on top of your signal of interest or (-38dBm). For reference, the signal at -130dBm is roughly equivalent to 1e-16W.

Disclaimer: The numbers above are general estimates used for illustration purposes. Actual conditions may vary, but it is unlikely that they will vary in such a way that will let you reliably recover your signal of interest.
Your -130dBm signal is

Re:Fraud, sour grapes, or late complaint? (4, Funny)

davidwr (791652) | more than 2 years ago | (#38748850)

that will let you reliably recover your signal of interest.
Your -130dBm signal is[end of text]

Well played, sir, well played.

My GPS equipment. (3, Informative)

queazocotal (915608) | more than 2 years ago | (#38748102)

Garmin GPS-12 13(?) years old.
Nagivo 3100, closing on 4 years old.
In addition, many GPS receivers in general aviation aircraft are _significantly_ more expensive than domestic units, and are not replaced merely because the battery wears out.

Re:My GPS equipment. (-1)

Anonymous Coward | more than 2 years ago | (#38748192)

Did you even read the article?

Re:My GPS equipment. (2)

CompMD (522020) | more than 2 years ago | (#38748416)

You might be surprised how many GPS 12s are out in the wild. They (and their derivative devices for Marine and Aviation) are darn near indestructible. I have a GPS 12, I use it when I need to measure distances outdoors. Then again, I also have a GPSMAP 696, GPSMAP 740, GPSMAP 175, GPSMAP 195, GPSMAP 295, Streetpilot Colormap, iQue 3600, iQue m5, Streetpilot c330, Forerunner 310XT, and GPS 72, and that's all on one shelf. Yeah, guess what I do...

Re:My GPS equipment. (2)

drinkypoo (153816) | more than 2 years ago | (#38748438)

My first GPS was a GPS 12 I got on sale at West Marine. Ordered up connector kits from canada and made a wall wart/DB9 cable and a 12V/palmpilot cable. Still have it, still works great. It takes slightly longer to acquire than some units but if you set it down with a clear view it's usually pretty good.

Re:My GPS equipment. (1)

CompMD (522020) | more than 2 years ago | (#38748464)

Comments like this make my day. :)

Re:My GPS equipment. (1)

drinkypoo (153816) | more than 2 years ago | (#38749158)

The only quibble I have is that I would have had to pay more for an external antenna jack. For what it is, it's a gem - back then the interface was actually quite good :) I also remember being really impressed with the connector, which was built to last. My modern navigation-type GPSes keep killing power connectors.

Re:My GPS equipment. (2)

ChikMag777 (1337235) | more than 2 years ago | (#38748694)

I have a GPS 12, I use it when I need to measure distances outdoors. Then again, I also have a GPSMAP 696, GPSMAP 740, GPSMAP 175, GPSMAP 195, GPSMAP 295, Streetpilot Colormap, iQue 3600, iQue m5, Streetpilot c330, Forerunner 310XT, and GPS 72

It sounds like you could have provided all of the test units for this experiment.

Re:My GPS equipment. (1)

DG (989) | more than 2 years ago | (#38748784)

Do you work for Garmin?

If so, that would be awesome, because I have some questions for a Garmin engineer.

DG

Re:My GPS equipment. (1)

CompMD (522020) | more than 2 years ago | (#38749710)

Fire away.

Re:My GPS equipment. (4, Funny)

ColdWetDog (752185) | more than 2 years ago | (#38749340)

Yeah, guess what I do...

You get lost a lot?

Big problem with that theory (4, Insightful)

Zouden (232738) | more than 2 years ago | (#38748110)

What possible motive do the GPS manufacturers have for rigging the tests? If modern, properly-configured GPS units don't recieve interference, then why would they care? I read the article expecting some important link, like Garmin having an alliance with Verizon, but there was no mention of that.

In fact if anything, GPS makers would enjoy selling modern units to customers with older units that no longer work because of LightSquared.

Sorry, but it's just too much of a stretch to believe in this conspiracy. I think LightSquared are simply desperate to get the FTC to give them their waiver. Their business is royally screwed without it.

Yes, but ... (0)

Anonymous Coward | more than 2 years ago | (#38748216)

I thought you were onto something for a minute, but it does an equipment manufacturer's brand no good if older equipment stops working for "reasons unknown". People have a right to expect 5-10 years out of a GPS receiver, warranty or no. It's in their interests to field all their old equipment.

And it's in everyone's interests for a company that admits it renders some equipment useless, but is not offering to replace such equipment FoC, while it reams profits in from the use of the airwaves, to fuck off and die

Re:Big problem with that theory (1)

mSparks43 (757109) | more than 2 years ago | (#38748302)

I don't think it was "rigged". so much as trying to ensure:
From TFA

LightSquared is seeking a waiver from the Federal Communications Commission (FCC) that requires all harmful interference with GPS to be resolved.

But I have no idea what LTE is.

Re:Big problem with that theory (4, Insightful)

HornWumpus (783565) | more than 2 years ago | (#38748450)

LTE often called (one of the underlying technolgies) 4G.

I think lightsquared is pissed because they thought they had paid enough bribes and now somebody isn't delivering.

There are old receivers in use (5, Interesting)

joe_frisch (1366229) | more than 2 years ago | (#38748116)

A lot of aircraft GPS receivers are quite old. It can cost 10-20K$ to put a certified receiver in a light aircraft, so pilots will keep their existing equipment as long as possible. Changing the requirements on interference resistance might require very expensive re-certifications of these receivers.

Re:There are old receivers in use (0, Troll)

Anonymous Coward | more than 2 years ago | (#38748186)

That's part of making sure your plane is ready to fly. Maintenance and upgrades.

Re:There are old receivers in use (1)

marcosdumay (620877) | more than 2 years ago | (#38748412)

Maintence is part of making sure the plane can fly. That's right.

But upgrades are only required if they'll lead to an increase in safety (and that increase is neeed at the first place). Just changing your GPS receivers won't.

Re:There are old receivers in use (0)

Anonymous Coward | more than 2 years ago | (#38748566)

You do realize that a small airplane may only costs almost that much without a fancy bunch of instruments but still IFR rated for something like 35k or less used. Yeah, I want to go buy a new GPS and have it installed for 20k because of some ass hats trying to cheat FCC regs by getting their spectrum redesignated. Oh, How about I get an experimental airplane redesignated as a commercial type without it passing a bunch of tests, because I feel there arbitrary. That way I could make a lot more money with minimum investment, too. I am not against getting some credit for the price of replacing or upgrading the units payed for by LightSquared. Even 1/2 off would be fine.

However, if the FCC where smart they would simple buy back the spectrum for a little more then auctioned it for. Re-designate it and action it off for it's new value.

Re:There are old receivers in use (1)

spire3661 (1038968) | more than 2 years ago | (#38749578)

If they were smart, they would tell Lightsquared back to the satellite with you. You made your bed, now lie in it. Oh and if you dont actually use the spectrum in the way you were licensed soon, we'll take it back with no refund.

Re:There are old receivers in use (4, Informative)

Martin Blank (154261) | more than 2 years ago | (#38748998)

And that's for a retrofit. What does one do (if something must be done) about units like a Garmin G1000 or the Avidyne units that have been installed in Cirrus planes for years? Factory-installed units intended to be core to aircraft operations are even more expensive than that.

Re:There are old receivers in use (5, Interesting)

AB3A (192265) | more than 2 years ago | (#38749642)

Parent post is quite correct. The largest cost of a GPS receiver in an aircraft is NOT the electronics itself, but the installation and certification process, not to mention the database updates.

Remember that it has to work with many other transmitters and receivers nearby, including a Mode C or Mode S radar transponder required for most metropolitan regions, a UHF (403 MHz) ELT, a pair of VHF transmitters, possibly an HF SSB radio or an old DME system, and maybe even a weather radar. --and that's just the stuff that is supposed to deliberately transmit. Receivers can radiate their local oscillators...

The bottom line is that when you put safety of flight navigation equipment in an aircraft, it has to be tested and certified before it can be used. Lightsquared would like us to just "replace it" with something new.

I'd like to put their executives in an airliner filled with their damned LTE phones landing on a CAT III approach on a dark and stormy night. We'll see how "rigged" those tests were.

Hmmm (3, Informative)

Lando (9348) | more than 2 years ago | (#38748278)

So LTE needs a federal license which requires proof that their network transmissions do not interfere with GPS receivers. Well, lets see, apparently the GPS equipment worked when the LTE network wasn't on and when it was turned on the GPS had issues. So what LTE is saying is that everyone with old GPS receives has to upgrade them because their network causes issues with them so that they can get a FCC license in order for their network to be deployed everywhere. Are they assuming that people buy all new electronics every year? I mean especially testing this on a military base, when I was in the military I used computers that were designed before I was born. I have a 30 year old television myself, if LTE decides to make a network that stops my television from working isn't that their problem. The whole purpose of the FCC license is to ensure that someone doesn't put new equipment into use that will stop the use of old equipment. Okay, maybe not the only purpose, but that one is at least important.

So LTE's network failed in real world conditions and they are blaming GPS manufactures for that failure. I don't think they have a case because the GPS manufactures likely did not go back in time and put in circuits to stop their equipment from running if they detected LTE's network. It's probably a good thing it wasn't raining either or they would have to sue God for conspiring against them.

Re:Hmmm (0)

Anonymous Coward | more than 2 years ago | (#38748342)

The article doesn't specifically mention the LTE vendor, and i'm off to do some googling, but does anyone know what vendor they're using, off-hand?

Re:Hmmm (0)

Anonymous Coward | more than 2 years ago | (#38749424)

The vendor is not the issue here. LightSquared is using a frequency band that interferes with GPS. LTE is configurable in that way.

Re:Hmmm (2)

MDMurphy (208495) | more than 2 years ago | (#38749028)

You've got it all a bit twisted. There's no entity called "LTE". The company is LiqhtSquared ( name is in the article title ) LTE stands for "Long Term Evolution" and refers to one of the newer mobile phone/data schemes.

Their claims may be valid (3, Interesting)

Walking The Walk (1003312) | more than 2 years ago | (#38748306)

According to TFA, the vendors

deliberately chose obsolete and niche GPS devices that would show the most interference ... The tests also included receivers that were tested without interference filters that normally would be included in a complete device for consumers

If true, the use of units without filters may be enough to invalidate the tests. It would be similar to testing a microwave for radiation leakage, with the door removed.

Re:Their claims may be valid (0, Informative)

Anonymous Coward | more than 2 years ago | (#38748646)

If true, the use of units without filters may be enough to invalidate the tests. It would be similar to testing a microwave for radiation leakage, with the door removed.

Except it's not true - an old GPS receiver without modern filters is still a GPS receiver. The military still uses receiver that were made WHEN THE NETWORK WAS CREATED for fuck's sake - that's not going to change, it's a network meant to assist in our national defense from foreign nations - ie: TO SERVE THE SOLE PURPOSE OF THE GOVERNMENT - these morons with political ties deserve to be run out of business.

Re:Their claims may be valid (1)

Anonymous Coward | more than 2 years ago | (#38748740)

Unless the the filters were unnecessary because the GPS was designed to operate in a band reserved for satellite to ground communications.

In other words receiver meets rules, LightSquared changes rules then complains that old receivers don't meet new rules.
    (Perhaps also without mentioning that meeting the new rules in a size and power limited device is unlikely.)

The test receivers should reflect the worst receivers out there, maybe after eliminating a few outliers that LightSquared is planning to replace.

Sooo not buying this load of crap (5, Interesting)

RogueWarrior65 (678876) | more than 2 years ago | (#38748350)

1) GPS manufacturers are not a direct competitor to a wireless networking company. If Verizon or AT&T were complaining they might have a case.
2) GPS was there first.
3) Clearly the Lightsquared hardware is spitting out a harmonic which could be fixed but would probably make the devices much more expensive to produce.
4) Lightsquared has been trying this case in the court of public opinion by running full page newspaper ads instead of dealing with the technology issues.
5) Lightsquared has been making huge political donations and receiving government grant funding which makes the whole thing stink like old fish.

Re:Sooo not buying this load of crap (1)

Anonymous Coward | more than 2 years ago | (#38748940)

1 - These folks have made a business by providing receivers that capitalize on a government deployed system, all they had to do to take advantage of a multibillion dollar infrastructure was make a competent device. Which they did not do - so the two businesses are in fact in direct conflict.
2 - This makes a case for squatting, the outcome of this precedence is not good for spectrum.
3 - Noone has stated that a harmonic is being put out at GPS. Harmonics operate at multiple of the frequency. LightSquared is at 1530 and GPS is at 1572. So while there is a concern with harmonics from broadcast at 750MHz, that isn't the case here. You could state intermod is a problem, but the testing hasn't even gotten that far. You could say this a case of desense/blocking/front end saturation.
4 - Dealing with the technology issues is what the testing is about, and now the opponents are trying to keep results from ever being opened. Unfortunately this fight has all been public relations to this point and engineering hasn't been given a chance despite the company's attempts to do so. So far they are getting murdered in public relations
5 - The donations issues has been explored and while the investor and CEO have made donations to parties, it's been fairly evenly distributed. If you want to look at this, I think you will find a lot of money going to a lot of folks on all sides of this.

Re:Sooo not buying this load of crap (1)

artor3 (1344997) | more than 2 years ago | (#38749634)

3- Sometimes you can get harmonics of the base clock frequency that sneak their way into the mixer and end up in the RF range. For example, if they were using a 14 MHz clock, its third harmonic would be 42 MHz, which could then get upconverted to 1572 and interfere with GPS. I don't actually know if that's the case (they could be using direct modulation for all I know, in which case they wouldn't even have this problem), but it is possible.

Re:Sooo not buying this load of crap (1)

spire3661 (1038968) | more than 2 years ago | (#38749646)

ON point #5, is it relevant that Lightsquared is greasing both sides of the aisle?

Really? Invalid Test? (4, Insightful)

bobbied (2522392) | more than 2 years ago | (#38748366)

All I can say to LightSquared is ... (sarcasm on) "Right...." (off) This company is *done* unless they can find a way to lower their required power or move their spectrum away from GPS. They are fighting for their very existence and it's getting down to the wire so they are saying *anything* in an attempt to keep things going. The test was rigged eh? Guess physics did you in guys, no need to rig the test. Had you asked an RF engineer you could have saved yourself a pile of cash trying to fight this issue. If the FAA didn't do this idea in because it would make Airborne navigation using GPS unreliable (and thus end the practice), the DOD's arguments should win the day. Further, the FACT that the consumer use of GPS would surely be impacted (if not totally disabled) for miles around their transmitters regardless of what they do should nail the coffin shut. I guess, to be fair, with the FCC buying tickets to the Broadband over Power Lines (BPL) circus, the chance that they'd buy into this sideshow was worth a try. However, the game is over guys.

They're full of it. (4, Informative)

phobos512 (766371) | more than 2 years ago | (#38748480)

LS is full of it. I used to do testing of this nature for the Navy. I know many of the people who would have done this testing for the USAF. Never in 6 years of working in that field did we ever require a contractor who had submitted equipment for test to do so with no knowledge of what the test would be. They are blowing smoke to cover their asses in the hope that "the right people" won't know any better.

Re:They're full of it. (1)

Anonymous Coward | more than 2 years ago | (#38748596)

To be fair, the military tells the company they're going to pass up front, then goes through the motions. All part of the contracting game. "We're looking for a supplier with the first initial K, last initial R, three letters. Please submit bids."

Re:They're full of it. (0, Informative)

Anonymous Coward | more than 2 years ago | (#38749138)

I wish that myth were true; it would make my job earlier. Instead it's "The contracting laws are so arcane that only 3 companies can comply with them, and only 1 can actually do the work. We'll competitively bid this, one that can't do the work will win, the other two will protest, and a bunch of small companies will complain, even though they don't have the 1000 man army required to attempt to comply with the FARs. Then, the one that (ultimately) wins will sub it out to the one who can do it, for their 10% passthrough, who in turn will sub it out to their subs for a 10% passthrough, who will not get it right because they will only do what they're contracted to, and the prime contract doesn't actually state that it has to work, because the prime intentionally left that out of the contract to "reduce risk". So, we get a shitty, incomplete system that meets the shitty requirements we got from the customer who doesn't know what he needs, so requires the shit he saw in popular mechanics or some vendor presentation."

Well it will cause issues (2)

koan (80826) | more than 2 years ago | (#38748542)

The spectrum bleeds so there will be interference, though it remains to be seen how much.
Falcone is certainly paying fof his chance to get Light squared going.
http://www.bloomberg.com/news/2011-09-20/house-republicans-ask-white-house-for-records-of-falcone-contact.html [bloomberg.com]
But that's business as usual.

However the claim is that the Lsquared signals are a "billion times greater in strength" than GPS, and I know my modern GPS unit seems to have trouble locking on at times.
http://www.insidegnss.com/node/2498 [insidegnss.com]

Lsquared seems like a great opportunity for rural areas to get high-speed Internet and maybe it's time we updated our GPS satellites again, but from my perspective after what I have read from multiple sources I am going to go with Light squared will cause issues with commercial GPS and the motivation on Lsquared's part is being the only provider in the area, charging a higher fee for access, and not having to lay cable and other infrastructure thereby reducing deployment and maintenance cost, in other words a large profit margin, and the only problem is they have to destroy the GPS infrastructure already in place.

Not just airplanes, but survey equipment is pricey (3, Interesting)

ChronoSphere (814014) | more than 2 years ago | (#38748610)

For surveyors, GPS basestations + roamers used for surveying are in the $10,000+ dollar range, and you don't replace them every few years.There's always going to be significant amounts of "old" (and old in terms of the 2-year churn for mobile phones) GPS equipment being used by the folks who need extremely high levels of accuracy.

screw LTE (1)

Anonymous Coward | more than 2 years ago | (#38748660)

I recall the Garmin GNS-430 aviation nav/com/gps suite is one of the affected units by the LightSquared towers. Yes it's "old", ie: it's been available for about 10 years, but there are hundreds of thousands of units out there flying every day. Is it obsolete? Well, not really, they still can get repaired and spares are still available. Is it a niche product? Sure, if you consider aviation safety a niche.

Given today's world dependency on GPS, that spectrum should be vehemently protected.

Re:screw LTE (1)

Anonymous Coward | more than 2 years ago | (#38748966)

Yes, the GNS 430 is one of the "niche" devices they mention, and it is severely affected. The level of interference is so great, that if there is a LightSquared tower within 5 miles of an airport, you can't shoot a GPS/WAAS approach. In IMC, if the airport (and aircraft) don't have ILS, as a pilot, you're screwed.

Information? (0, Offtopic)

lightknight (213164) | more than 2 years ago | (#38748750)

Forgive my ignorance, but I am gathering very little information on Light Squared. They haven't really been on my radar.

What is this company? What are they attempting to offer? And what's all this hubbub about it?

Re:Information? (0)

Anonymous Coward | more than 2 years ago | (#38748942)

A rich snob is trying to get cheap entry into the mobile phone infrastructure game by getting usage rights to portions of the EM spectrum that are reserved for low strength (at ground) signals and putting in high power transmitters.

He has been actively bribing government agencies, but apparently was unable to bribe enough of the FCC to convince them to allow the change that would make over 90% of the in-use GPS systems (civilian and military) useless when anywhere nearby the LightSquared towers.

Re:Information? (1)

Anonymous Coward | more than 2 years ago | (#38749052)

LightSquared is a company started by scammers looking to make a huge pile of cash by circumventing FCC rules.
They bought a cheap chunk of satellite only communication bandwidth spectrum near the GPS band which no one wanted.
They poured a ton of money into bribing everyone they could find to get it approved as a terrestrial comms band so they could roll out a nationwide high speed broadband network and make a killing as their costs for obtaining the spectrum were close to zero.
The FCC was bribed enough to approve it provisionally with a condition for final approval based on test of GPS receivers. They were going to issue final approval but the US Navy stepped in and said - whoa you idiots are going to mess up our ballistic missile systems. That put a halt to it real quick.
Predictably the ultra high powered terrestrial comms equipment flooded the filters on the old GPS receivers and caused them to malfunction.
Lightsquared is on its last gasps trying desperately to get the FCC to issue final approvals.

It's not about filters or defective GPS design (5, Informative)

Anonymous Coward | more than 2 years ago | (#38748772)

it's not about filters, nor is it about "GPS listens outside its band"

GPS receivers have "wide open" front ends and always have for good engineering reasons:
1) Spectrum planning ensured that there's no high power signals in adjacent bands (i.e. the adjacent band is also for satellite signals)
2) "brick wall" filters are heavy, expensive, large, and have bad effects on the inband signals (see, e.g. any digital audio application since CDs started being sold 30 years ago). Your cellphone has GPS that is as small as it is partly because you can use a fairly wide open front end that doesn't require a lot of filtering.
3) GPS signals are below the noise floor, allowing use of 1 bit ADCs in receivers, reducing cost and complexity in receivers.

There's quite a bit of arguing about what is an appropriate propagation model from L2 terrestrial transmitter to GPS victim. L2 would like to use a conventional communication model. GPS folks would like to use a jammer/interference model. The difference isn't in the "mean power" but is in where the outliers are. For comm, your concern is that your worst case low power deviation is still high enough that you can "close the link" (i.e. not drop the call). For interference, your concern is that the worst case high power deviation is still low enough that it doesn't interfere with your link. The problem is that in urban environments, the distribution isn't uniform and is highly skewed (lots of reflecting surfaces and multipath.. distance isn't as big a factor as just the number of bounces). There's lots of deviations below the mean, but small ones, and relatively few deviations above the mean, but they are huge (e.g. "hot spots"). We're talking 15-20 dB difference between the 5% low end and the 5% high end

There's also arguing about what "performance degradation" is acceptable. L2 would like to claim that 6-8 dB is ok, while GPS industry would like to use 1dB. That's because communications uses error correcting codes and such, and can tolerate dropouts and degradation. GPS is more like radar, and relies on measuring the timing of the signal, and doesn't have as much in the way of error correction or error tolerance, so they've historically used the radar standard of 1dB degradation. The GPS industry is a bit stretching here, because with new receiver designs (which might consume more power and be bigger) they could probably deal with the worse interference environment. But that's a 10-20 year kind of project.

So the tests were fair, with published test criteria, and only now, a week from their deal with Sprint expiring (after a 30 day reprieve) they're starting to raise these questions.

The test sounds proper IMHO. (4, Funny)

Lashat (1041424) | more than 2 years ago | (#38748818)

Besides nobody ever flew into a mountian because they didn't have a clear LTE signal.

non-disclosure agreement (0)

Anonymous Coward | more than 2 years ago | (#38748968)

Which part of "non-disclosure agreement" these execs do not understand talk about it to reporters???? It seems like a potential lawsuit is coming.

does the emission "it" interfere? (0)

Anonymous Coward | more than 2 years ago | (#38749548)

Then there ya go. So, Fuck this interference. Make the god damn decision. You regulate power and frequency in the PUBLIC INTEREST, So, L2, They're fuckin out. Let em get the hell on with life. This isn't about one inventor destroying much spectrum intermittently. If I was a public FCC vote I would vote to tell lightsquared lights out, Im sorry no. Don't hang them up in legal limbo like gibson guitars, where they build then get raided. They interfere with the spectrum we use for important stuff.

Yet another part of me say's who cares, they don't listen to what I say about haarp technology (in multiple locations and countries) either. (Silence is all we hear)

If you want to bleed to succeed then use a CB radio thank you.

Yadda yadda yadda (0)

Anonymous Coward | more than 2 years ago | (#38749846)

Another "the dog ate my homework" excuse from Obama lackeys who got caught with their hands in the cookie jar.

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