Lightsquared and GPS system

ScottM said:
The TRFS15011 is the most flexible and robust GPS receiver on the market. The integrated circuit has the ability to process L1 and L2 received signal data in the presence of a >60 dBc jammer and easily integrates into a complete system platform solution.
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So this cool dohicky can handle a jammer signal that is about a million times greater than the GPS signal (you RF guys can verify that I converted dBc right. I'm just a lowly physicist)

Isn't the LightSquared stuff, more like a billion+ times more powerful in the vicinity of the transmitter.

Edit: Aaaaand, its an L1/L2 reciever which means it is probably using the non-civilian codes to get that great jammer resistance. Summary, this is a military reciever and is not available to the general public, but should make the DoD happy.
 
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COFlyBoy said:
Edit: Aaaaand, its an L1/L2 reciever which means it is probably using the non-civilian codes to get that great jammer resistance. Summary, this is a military reciever and is not available to the general public, but should make the DoD happy.
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:idea:

There ya go.


Who is the biggest objector to Lightsquared? :idea::idea::idea:
 
So Lightspeed's proposal again is to not back down, blame the existing tech. And Oh here.....you should reconfigure your existing hardware. That's fine for maybe a high end Garmin or military.... but what about all the cheaper devices that will still be obsoleted.

http://www.engadget.com/2011/09/21/lightsquared-proposes-simple-affordable-solution-to-that-pesk/

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Cellphones, Wireless
LightSquared proposes 'simple, affordable solution' to that pesky GPS interference issue

By Donald Melanson posted Sep 21st 2011 2:22PM

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It's not the first "solution" that LightSquared has proposed for the GPS interference issue that's gotten in the way of its LTE network rollout, but the company's now touting a new "simple, affordable solution" to the problem. That doesn't actually involve any changes to the network itself, but rather changes to the high-precision GPS hardware that is being interfered with. To that end, the company has announced that it's signed an agreement with Javad GNSS, which says that it's been able to reconfigure the filters and linear amplifiers used on existing receivers and make them "completely compatible with LightSquared's bottom 10 MHz of spectrum." According to Javad, those changes are not expected to increase selling price of newly reconfigured devices for consumers, although there would presumably be some cost to retrofit existing devices (the first units for testing are expected to be available next month). So, it may be "simple" and "affordable," but it doesn't seem like it's necessarily an "easy" solution. LightSquared's press release is after the break.
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TripleZ said:
So Lightspeed's proposal again is to not back down, blame the existing tech. And Oh here.....you should reconfigure your existing hardware. That's fine for maybe a high end Garmin or military.... but what about all the cheaper devices that will still be obsoleted.
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Without going SZ, do we really want to spend the very limited DoD funds to replace all the GPS equipment out there in the military? How dumb would that be?
 
Hmm. Something that triggers "mandatory' big DoD spending always gets my attention. Ever think that might be part of the theater?

Hard to say. Really depends a lot on who's paying. The money and relationship trail hasn't been followed yet.

Any relationships or investments by the Lightsquared folks in this other receiver company? Worth a look.
 
denverpilot said:
Hmm. Something that triggers "mandatory' big DoD spending always gets my attention. Ever think that might be part of the theater?

Hard to say. Really depends a lot on who's paying. The money and relationship trail hasn't been followed yet.

Any relationships or investments by the Lightsquared folks in this other receiver company? Worth a look.
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Yep, the old "boogie man" fear factor is always a risk... risk that real cost impacts will be dismissed
 
Well I guess if L² has found the cure for the problem THEY cause with all the GPS's then they can retro fit all the units with the new filters.
 
Gary F said:
LightSquared is backed by some very rich and politically well connected people.

http://campaign2012.washingtonexaminer.com/article/soros-turns-obamas-lightsquared-imbroglio
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Partisan politics completely aside... That article is a very good example of completely sociopathic business and ethical behavior.

It worries me a lot that these people control both Parties. Doesn't seem to bother the masses much yet, though.

Don't worry, Lightsquared will be "too big to fail" soon enough. We'll be paying to clean it all up.
 
denverpilot said:
Partisan politics completely aside... That article is a very good example of completely sociopathic business and ethical behavior.

It worries me a lot that these people control both Parties. Doesn't seem to bother the masses much yet, though.

Don't worry, Lightsquared will be "too big to fail" soon enough. We'll be paying to clean it all up.
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Gotta protect Obama's investment :D
 
Agreed. I'm no O fan, but there's plenty of boondoggles like this one to go around, in D.C. in all walks of government.

The assumption/delusion that we all operate under is that anyone actually goes to D.C. for our good first, and theirs second.

We all want to believe the "Mr. Smith Goes to Washington" story and that Potter wouldn't have ended up crushing the Bailey Savings and Loan in a different yet adorable Jimmy Stewart flim.

It's kinda funny really, Jimmy Stewart himself was a Brigadier General and fought real political battles in Congress. He knew the score, but there's good money in making movies that depict the good guys always winning. ;)

Look at the number of cop shows on TV where the good guys always get the bad guy. It's an enormous meme in our society. The only time a TV cop ever loses is when the writers need to write him/her out of next year's season. ;)

Even "reality" cop shows never show the traffic stops of law-abiding folks who sue the officer and win, only the derelicts of society getting thumped with a nightstick and told "don't move!" while the audience cheers.

Maybe that's why I like Wipeout so much. "You're going to run through a maze that's going to kick your butt, and we're going to make fun of you. If you jump through the hoops the fastest, we'll give you $50K".

It seems more like real life.

Who hasn't tried to jump to the big bouncy red ball and been tossed like a rag doll into the lake in real life? We all have!

And my goodness, do I love watching humans bounce! ;)

Statistically I bet tenacious people "win" stuff in real life whether they're good or bad ethically and morally.

That's not a condemnation of either one, other than our society is constantly and gently lying to us about "good guys vs. bad guys".

If the Lone Ranger were real, he'd have been seen as a prick who couldn't keep his nose out of other people's business. Ya know?
 
And LS take the offensive again today....

Link

Recently, concerns have been raised about interference with GPS devices. We take these concerns very seriously. Despite the fact that the interference is caused by others' inappropriate use of LightSquared's licensed spectrum, we have been proactive in working toward a solution to the GPS issue. We are making a $150 million private investment in the solution for GPS. We have moved our spectrum farther away from the core GPS frequencies and at the request of the FCC, we set up, funded, and ran the largest and most comprehensive testing program this country has ever seen.

....................
With 99.5 percent of all commercial GPS interference accounted for and solved, LightSquared has now tackled solving the remaining .5 percent of GPS interference occurring on precision devices that also inappropriately violate our licensed spectrum. We have partnered with established GPS manufacturers to develop technology that eliminates interference issues for high-precision GPS devices, including those in the agriculture, surveying, construction, and defense industries. Pre-production designs are already in testing; once completed, this technology can be implemented simply, quickly, and inexpensively into GPS devices.
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Jim Logajan said:
A receiver can never "violate" spectrum, but they know that.
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That os true. But some receivers may not be able to reject interference that is within the regulatory framework
LS. Is trying to make the case that they are within specs. Thus the problem is with the receiver.

Disclaimer: these are my personal thoughts and are not to be construed as official position.

Sent from my Milestone using Tapatalk
 
wsuffa said:
And LS take the offensive again today....

Link
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It's amazing how simple it seems to LS that the problem can be solved by letting all affected parties replace their equipment at their own expense.
 
gismo said:
It's amazing how simple it seems to LS that the problem can be solved by letting all affected parties replace their equipment at their own expense.
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It is not all that unusual. I know a PoA member's company forced that upon another company that complained about interference. The regulators of the country looked at the complaint. Decided that the telecom operator was not operating outside of their license and forced the company that was complaining to replace and/or add additional filters at their own cost.
 
wsuffa said:
What's a little outright misinformation when the whole project is at risk?
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Their whole project was "at risk" when they couldn't get their satellites to do what they wanted them to do.

The switch to ground-based stations is the key to the Bravo Sierra.
 
ScottM said:
It is not all that unusual. I know a PoA member's company forced that upon another company that complained about interference. The regulators of the country looked at the complaint. Decided that the telecom operator was not operating outside of their license and forced the company that was complaining to replace and/or add additional filters at their own cost.
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There's also a long tradition in the US of not requiring receiver performance standards or filters on receivers. The Mexican Standoff between the FAA and FCC goes back, oh, 30 years (at least on the topic of high powered FM transmitters to aviation NAV receivers). At one point, said standoff resulted in various NOTAMS or modifications to instrument approaches because they were unusable as a result of interference to some receivers. The topic was even the subject of an ITU study group (as well as RTCA).

So, yes, it's entirely possible that a similar result may occur here - unless the interference to military systems and critical infrastructure occurs. Too much money at stake.

One more reason to keep your VOR/ILS and DME receivers.
 
wsuffa said:
There's also a long tradition in the US of not requiring receiver performance standards or filters on receivers. The Mexican Standoff between the FAA and FCC goes back, oh, 30 years (at least on the topic of high powered FM transmitters to aviation NAV receivers). At one point, said standoff resulted in various NOTAMS or modifications to instrument approaches because they were unusable as a result of interference to some receivers. The topic was even the subject of an ITU study group (as well as RTCA).

So, yes, it's entirely possible that a similar result may occur here - unless the interference to military systems and critical infrastructure occurs. Too much money at stake.

One more reason to keep your VOR/ILS and DME receivers.
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I was just having that conversation with a friend this morning. I'm at EMC Europe in York and was talking with a consultant who has done some work for Lightsquared earlier this year. His claim is that the prime GPS receivers that suffered interference were the ones in mobile phone, that a filter that cost $0.05 more per unit would have solved their issues. Their front ends are open to too much spectrum. It's not that Lightsquared is radiating in the GPS band, it's that some GPS receivers do not adequately reject signals outside the band. Lightsquared has moved to a channel 10 MHz farther away from the GPS band and that, he says, has helped greatly.

As to keeping VOR/ILS and DME, I couldn't agree more. Nice to have backups that are independent of another navigation system.
 
Ghery said:
His claim is that the prime GPS receivers that suffered interference were the ones in mobile phone, that a filter that cost $0.05 more per unit would have solved their issues. Their front ends are open to too much spectrum. It's not that Lightsquared is radiating in the GPS band, it's that some GPS receivers do not adequately reject signals outside the band. Lightsquared has moved to a channel 10 MHz farther away from the GPS band and that, he says, has helped greatly.
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That's precisely the issue with FM broadcast adjacent to NAV. Brute-force overload & intermodulation. Both easily resolved with inexpensive filtering in the front end of NAV receivers.
 
wsuffa said:
That's precisely the issue with FM broadcast adjacent to NAV. Brute-force overload & intermodulation. Both easily resolved with inexpensive filtering in the front end of NAV receivers.
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"Inexpensive" only if you are going to buy a new nav receiver anyway.
 
Bob Noel said:
"Inexpensive" only if you are going to buy a new nav receiver anyway.
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I made that point to him, as well. I pointed out that Garmin is no longer manufacturing the GNS 430/530 and that the chances of them designing a retrofit and getting it FAA approved were somewhere between 0 and nonexistent. He said that at one point Lightsquared was considering just giving anyone impacted a new device to replace the one suffering interference, feeling that would be the least expensive fix for them. Anyone need a free upgrade to Garmin's new offerings? :D
 
Ghery said:
Anyone need a free upgrade to Garmin's new offerings? :D
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Does anyone know if Garmin's new offerings actually have filters that would make them immune? Those units may yet need their own hardware revision...
 
Ghery said:
I was just having that conversation with a friend this morning. I'm at EMC Europe in York and was talking with a consultant who has done some work for Lightsquared earlier this year. His claim is that the prime GPS receivers that suffered interference were the ones in mobile phone, that a filter that cost $0.05 more per unit would have solved their issues.
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The testing done in western USA found significant interference with ALL units tested including a Garmin 430W IIRC

Their front ends are open to too much spectrum. It's not that Lightsquared is radiating in the GPS band, it's that some GPS receivers do not adequately reject signals outside the band. Lightsquared has moved to a channel 10 MHz farther away from the GPS band and that, he says, has helped greatly.
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LS has proposed that they be allowed to operate their network in the lower portion of the (space based) spectrum they own, increasing the offset from a few MHz to 10 or more. That will indeed reduce the problems for many receivers although the necessary testing hasn't been conducted to determine exactly what effect there would be on all users. But even if this does eliminate all issues with most GPS navigators, they also have stated that this is intended to be a stopgap measure with them going back to their original plan in a couple years.
 
gismo said:
But even if this does eliminate all issues with most GPS navigators, they also have stated that this is intended to be a stopgap measure with them going back to their original plan in a couple years.
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Well, it actually isn't going back to their original plan, it's going back to the kludge they came up with to make the system work when they realized that the original satellite based solution wouldn't provide the benefits they hoped for. But yes, your point stands, that they are still expecting to be able to fully utilize the spectrum adjacent to the GPS signal in the future.
 
Wow. Talked with someone who might get involved with the official testing today. Incredibly thorough RF engineer. I think he'd do a fabulous job.

The rabbit hole goes incredibly deep and insane amounts of money at stake.

And now, like Scott, I can't say more, other than my opinion that they're attempting one of the biggest end-runs around the spectrum management system ever. And that it's going to cost us all a fortune in multiple ways but certainly in dollars just to do the research, before it's all done.

The question is... How much money do the GPS manufacturers have in their war chest? The longer this goes on, the higher Garmin's prices will go. Lawyers, RF Engineers, and politicians aren't cheap.
 
denverpilot said:
The longer this goes on, the higher Garmin's prices will go. Lawyers, RF Engineers, and politicians aren't cheap.
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One of those three things is very cheap. BTW it is a pretty well known thing in the KC area that Garmin pays some of the worst wages for RF engineers. I work with a lot of former Garmin employees. They liked the company, liked the working conditions, but hated the pay.
 
denverpilot said:
Wow. Talked with someone who might get involved with the official testing today. Incredibly thorough RF engineer. I think he'd do a fabulous job.

The rabbit hole goes incredibly deep and insane amounts of money at stake.

And now, like Scott, I can't say more, other than my opinion that they're attempting one of the biggest end-runs around the spectrum management system ever. And that it's going to cost us all a fortune in multiple ways but certainly in dollars just to do the research, before it's all done.

The question is... How much money do the GPS manufacturers have in their war chest? The longer this goes on, the higher Garmin's prices will go. Lawyers, RF Engineers, and politicians aren't cheap.
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Can't the filter just be in a separate box inline between the antenna and receiver? Or just build it into a replacement antenna which Lightsquared can provide. Or just buy me a premodified 750, I'd be fine with that. Considering the money at stake on their end, there ain't that many 750s to buy. For those of you that don't know about the Mobil 1 Synthetic debacle on a whole lot of Continental TSIO 520s I know, and the GTSIOs as well. Mobil bought a lot of engines over that oil.

You never know, Light Squared stands to make a lot of money, but I haven't totally heard what capability they are going to give me. However, if Light Squared is willing to eat the cost of refitting everyone's gear, there's no reason that they can't be given the entire bandwidth and we can piggyback the GPS signal into the data stream as a second system of delivery. At the same time we can piggyback weather and traffic and all the ADS-B stuff through the same data stream. The goal of having a single full nation, preferably full world (well, 70N-70S at least) system that people can use everywhere. We already have these systems but the capacity is limited and they have latency issues as well as being very expensive for moderate broadband speed, say DSL or worse depending on atmospherics and angles, and that was with VSAT. Thing is, you don't need satellite everywhere. I'll vote to give them the go ahead as long as they produce a system where I can travel anywhere 70N-70S (this is the area of the globe INMARSAT covers with 3 satellites) and be in full communications in voice and data at all times (may be slower when in Satellite Only coverage areas, but there you won't have a problem receiving the direct signal from the GPS birds. So you basically have your GPS antenna and the specialized Light Squared antenna that also receives GPS and incorporates their receiver and filtering. We can then get the rest of the data feed as well. The system could also add towers to the GPS "Constellation" which could amazingly improve vertical accuracy.
 
Which part of "they don't have any operational satellites that do anything useful" did you miss?

This is a land-based spectrum-grab hiding under the guise of a satellite company.
 
Henning said:
Can't the filter just be in a separate box inline between the antenna and receiver? Or just build it into a replacement antenna which Lightsquared can provide. Or just buy me a premodified 750, I'd be fine with that. Considering the money at stake on their end, there ain't that many 750s to buy....
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I don't think so. Any passive filter would result in an unacceptably high attenuation of the GPS signal. Even if a filter could be designed how would devices like cell phones be retrofitted? This is not a viable solution and LightSquared knows it.
 
denverpilot said:
Which part of "they don't have any operational satellites that do anything useful" did you miss?

This is a land-based spectrum-grab hiding under the guise of a satellite company.
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And that is the crux of the issue. The RF engineers and front-end designers were given one set of specs (space-based systems in adjacent frequency bands) and the receivers will now be exposed to a different set of specs (ground based system). Materially changes the parameters.

Scott's right about engineers - not just Garmin - compared to other professions, the engineers are paid substantially less. Even for engineers with advanced degrees and licenses (PE).
 
Gary F said:
I don't think so. Any passive filter would result in an unacceptably high attenuation of the GPS signal. Even if a filter could be designed how would devices like cell phones be retrofitted? This is not a viable solution and LightSquared knows it.
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Are cell phones critically effected? My understanding was the problem was with precision units mostly. Cell phones seem to have "enhanced GPS" off the towers as well. Besides, how long does a phone last? A couple years at the outside? Most of us are good for a cheap upgrade to a top model after a year.

Even if they have to replace every existing GPS receiver it won't sum up to a year's profits one it rolls and they accept that as the possible solution.
 
Henning said:
Are cell phones critically effected? My understanding was the problem was with precision units mostly. Cell phones seem to have "enhanced GPS" off the towers as well. Besides, how long does a phone last? A couple years at the outside? Most of us are good for a cheap upgrade to a top model after a year.

Even if they have to replace every existing GPS receiver it won't sum up to a year's profits one it rolls and they accept that as the possible solution.
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GPS is necessary to identify the location of the phone during a 911 call.
 
denverpilot said:
Which part of "they don't have any operational satellites that do anything useful" did you miss?

This is a land-based spectrum-grab hiding under the guise of a satellite company.
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I didn't think they did nothing useful, just that they don't have the bandwidth to support the volume. Like I said, IF they can provide seamless service across the entire nation, it's worthwhile. If they can do it around the globe no roaming it's a freakin miracle. If they can do all that afford-ably, best get your affairs in order because the world's about to come to an end.
 
Well, if they can get through the problem by paying to replace every "mission critical" GPS unit (with the definition of "Mission Critical" written by... me... with assistance for technical stuff from, say, Scott and Lance)...
 
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