Federal Body Concludes LightSquared Can't Work with GPS

CommanderFrank

CommanderFrank

Cat Can't Scratch It
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In what can only be described as a major setback to the proposed LightSquared LTE network, the National Space-Based Positioning, Navigating and Timing Executive Committee (can you tell by the name that is a government agency?) :eek: found that there is no way to make the network safe to operate without interfering with GPS services.

"Based upon this testing and analysis, there appear to be no practical solutions or mitigations that would permit the LightSquared broadband service, as proposed to operate.”
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I have to agree with Lightsquared that it doesn't sound like the test was conducted very fairly.

Quote: ' It said the vice chairman of the advisory board, Bradford Parkinson, simultaneously was on the board of directors of Trimble Navigation, a foe of LightSquared's plan.'

GPS company cuts corners to save a small amount per unit manufactured, finds out later 'oops, we made a bunch of units that can't handle something that would have been handled with the proper filter' and then has one of their board of director's be the Vice Chairman of the advisory board that (surprise surprise) recommended against Lightsquared? Yeah, that doesn't seem awfully convenient at all. :rolleyes:
 
This is a bummer.. I was hoping LS would take off & give a viable option to people stuck with low speeds currently.
 
At first I also thought that the FCC and the GPS companies were ganging up on poor LightSquared to push them out of business but as I understand from reading about this debacle on other sites it really is LightSquared's problem.

They bought satellite spectrum but want to use that spectrum from terrestrial towers. The problem is that, yes the GPS receivers should be filtering out that spectrum, but they were designed to filter out that signal coming from orbit, not from a tower just a few hundred miles away. Having the signal emanating from a tower here on the ground instead of a satellite 22000 miles away overwhelms the receiver's filters.

Think of it this way, you have a telescope with a camera with some software to filter out everything but blue starlight. So far so good but then someone puts a lightpost next to your telescope. They say it shouldn't be a problem since it is an incandescent and is mostly putting out white/yellow light and your camera is filtering out everything but blue anyway. I think you can see why the lightpost is an issue.

This is my basic understanding of the issue, so feel free to correct me, but there is more to it than everyone's out to get LightSquared.
 
No sympathy to Lightsquared from me. GPS is too important to allow it to be endangered just so a broadband provider can run their business.
 
Ualdayan said:
I have to agree with Lightsquared that it doesn't sound like the test was conducted very fairly.

Quote: ' It said the vice chairman of the advisory board, Bradford Parkinson, simultaneously was on the board of directors of Trimble Navigation, a foe of LightSquared's plan.'

GPS company cuts corners to save a small amount per unit manufactured, finds out later 'oops, we made a bunch of units that can't handle something that would have been handled with the proper filter' and then has one of their board of director's be the Vice Chairman of the advisory board that (surprise surprise) recommended against Lightsquared? Yeah, that doesn't seem awfully convenient at all. :rolleyes:
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Not that simple. Lightsquared wants to put in very powerful ground based transmissions in which is where all these problems come in. If it was satellite based as they were originally speced to do then there would be less problems caused.
 
bacon said:
Not that simple. Lightsquared wants to put in very powerful ground based transmissions in which is where all these problems come in. If it was satellite based as they were originally speced to do then there would be less problems caused.
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THIS. Lightsquared has been playing the victim here, but their technology as it exists just nerfs GPS. I've yet to see them refute the claims of the contrary parties with anything more than pleading persecution. Facts, or GTFO.
 
ianken said:
THIS. Lightsquared has been playing the victim here, but their technology as it exists just nerfs GPS. I've yet to see them refute the claims of the contrary parties with anything more than pleading persecution. Facts, or GTFO.
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They created a very cheap filter that completely solves the problem and offered it to the GPS companies for free.

This just seems like bullshit to me. The feds knew Lightsquared's business model when they allowed them to purchase the spectrum, now they're saying theres now way they can use it. Sounds like Lightsquared got scammed and the government unloaded some useless spectrum for a lot of cash.
 
wizdum said:
The feds knew Lightsquared's business model when they allowed them to purchase the spectrum, now they're saying theres now way they can use it. Sounds like Lightsquared got scammed and the government unloaded some useless spectrum for a lot of cash.
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LightSquare (LS) brought this problem on themselves.

LS spectrum license from the FCC was an experimental license for them to demonstrate their proof of concept. This is common for experimental/development work. It’s not a guarantee. The other note is the FCC didn’t want to issue this license to begin with. It was after LS called on favors to politicians (who received significant monetary political contributions from LS) did the FCC give the experimental licence.

LS problems aren’t just with the FCC but also with the International Telecommunications Union (ITU). The ITU is a body of the UN. It holds bi-annual World Radio Conferences (WRC) whereas the results are ratified back in the US by Congress and have international treaty like status. Within these agreements is the protection of GPS bands. All it takes is an international airlines to receive GPS interference landing into NY or DC and a formal EMI complaint is filed through the ITU…

If LS should have done their homework they would have realized this.
 
wizdum said:
They created a very cheap filter that completely solves the problem and offered it to the GPS companies for free.
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A filter that's already known to fail if LS's original 2X10 MHz network configuration, never been tested by the government or tested in actual field conditions, a filter that may or may not be fit the many different form factors used by GPS receivers and one that would need to be retrofitted on millions of devices, including many which would need recertification.

This just seems like bullshit to me. The feds knew Lightsquared's business model when they allowed them to purchase the spectrum, now they're saying theres now way they can use it. Sounds like Lightsquared got scammed and the government unloaded some useless spectrum for a lot of cash.
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LS didn't buy the spectrum from the government, they got it when the purchased the bankrupt assets of SkyTerra, a company who's business is in satellite communications. The licensed frequencies themselves are in part of the spectrum that is internationally recognized as being reserved for satellite communications and which the FCC has in the past stated that it would not allow a full terrestrial network to be built in and where Federal regulations forbid any interference from ground transmitters to other satellite users.

If LS did not know what its license actually allowed it to do, then they need to fire all their lawyers because they just caused a $2 billion mistake.
 
The feds told lightsquared from the start that their intentions would only be permitted ****IF**** they could be done without interfering with existing GPS systems. When it (unsurprisingly) turned out that a filter intended to protect against another satellite signal with a strength X, couldn't protect against a terrestrial signal with a strength of 10,000,000,000 X LS found themselves up a creek.

The more general problem is that it also means that the part of the FCCs spectrum plan to convert a significant amount of satellite spectrum into cellular spectrum to support mobile growth is likely in trouble since most systems will probably have the same type of filters unless they already need to deal with terrestrial interference.
 
wizdum said:
They created a very cheap filter that completely solves the problem and offered it to the GPS companies for free.

This just seems like bullshit to me. The feds knew Lightsquared's business model when they allowed them to purchase the spectrum, now they're saying theres now way they can use it. Sounds like Lightsquared got scammed and the government unloaded some useless spectrum for a lot of cash.
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Yeah, and some GPS companies already were filtering it out. It isn't a technological question like some try to frame it (eg they talk up how big the difference in signal power is and try to make it sound impossible, but plenty of things are commonplace now that SOUND pretty impossible like processors with billions of transistors doing trillions of operations per second). Lightsquared wasn't sold the spectrum recently though, so they weren't 'scammed' by the government, but it is wrong that some GPS companies are trying to make it sound like it's Lightsquared's fault their GPS devices didn't follow specifications as well as other GPS devices did.
 
Ualdayan said:
Lightsquared wasn't sold the spectrum recently though, so they weren't 'scammed' by the government, but it is wrong that some GPS companies are trying to make it sound like it's Lightsquared's fault their GPS devices didn't follow specifications as well as other GPS devices did.
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Why would GPS device manufacturers use filters to filter out a signal that was never supposed to be there and would be, and still is, illegal.

And even then, how would GPS manufacturers even know what filter to built considering the specifications of LightSquared's network, such as how many bands it uses, at what frequencies and what power levels weren't even known until 2010-2011.
 
SLee said:
Why would GPS device manufacturers use filters to filter out a signal that was never supposed to be there and would be, and still is, illegal.
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My understanding is that the GPS makers built their devices on the assumption that they would always have that empty space (which lightsquared now owns) as a buffer, and thus didn't bother filtering it as a cost-saving measure. Now we're stuck with useful spectrum we can't use.

That's what I've heard, anyway.
 
DeathFromBelow said:
My understanding is that the GPS makers built their devices on the assumption that they would always have that empty space (which lightsquared now owns) as a buffer, and thus didn't bother filtering it as a cost-saving measure. Now we're stuck with useful spectrum we can't use.

That's what I've heard, anyway.
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Not empty, the assumption was that the spectrum would be only for satellite communication, which was a reasonable assumption given FCC statements and regulations. It's a main reason why GPS was initially located there, because that spectrum was protected for satellite communication, and why the primary civilian signals from the new satellite navigation systems from Europe and China are also located at virtually the same frequencies.
 
LightSquared found itself the owner of rural gravel roads and wants to build super-highways over them. Sorry, but they are rural gravel roads for very sound technical and legal reasons.. no super-highways for you.
 
So right now Lightsquared paid billions for spectrum the governement KNEW they would never permit to actually be used?
 
BoogerBomb said:
So right now Lightsquared paid billions for spectrum the governement KNEW they would never permit to actually be used?
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To be accurate, LightSquared paid billions for spectrum licensed by another bankrupt company that LightSquared KNEW could never be permitted to be used to build a terrestrial network without proving that they would not interfere with GPS because LightSquared knew it could not afford the even more billions that would be needed to license spectrum where it could legally build a terrestrial network.
 
So how was this supposed to work, these filters? Stick my GPS devices inside them to be able to use them?
 
It's dead. Gone. Buried. There is absolutely NO way that the government would allow something to interfere with existing GPS devices under any circumstances.

Filters you say? Ok. How are you going to retrofit those filters (at no cost) onto millions of GPS devices that have been purchased by businesses and consumers since the mid-90s? Even if it was a simple firmware upgrade, it's just not going to happen...
 
In otherwords, now everyone knows what to do to completely black out the entire GPS system of any given region. I wonder what military benefit that has...
 
BBA said:
In otherwords, now everyone knows what to do to completely black out the entire GPS system of any given region. I wonder what military benefit that has...
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Gps makers have fucked themselves now. We know that the system can be brought down extremely easy because they were too cheap to add a few cents worth of protection thereby rendering valuable wireless spectrum useless for forever.
 
BBA said:
In otherwords, now everyone knows what to do to completely black out the entire GPS system of any given region. I wonder what military benefit that has...
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None, since things that emit high powered radio signals in a battlefield tend to die very easily.
 
Back in 2003 Saddam had what he thought was a network of GPS jammers covering his key command and control points. Most of them were destroyed by GPS guided bombs.
 
SLee said:
To be accurate, LightSquared paid billions for spectrum licensed by another bankrupt company that LightSquared KNEW could never be permitted to be used to build a terrestrial network without proving that they would not interfere with GPS because LightSquared knew it could not afford the even more billions that would be needed to license spectrum where it could legally build a terrestrial network.
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+1

Although, I honestly believe that LS did not have a subject matter expert advising them on FCC and ITU regulatory guidance. Anyone who has ever worked FCC RF spectrum licensing or processed a RF spectrum supportability assessment knows the devil is in the details (ie footnotes).

Met-AL said:
So how was this supposed to work, these filters? Stick my GPS devices inside them to be able to use them?
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To expand on what Nogami had mentioned, new GPS devices would be produced with the LS/GPS filter.

The probable answer is old GPS products would not be able to be retrofitted with a filter. The filter may be cheap but retrofitting is not.

I would guess that 99% of the GPS products in the consumer market would be considered throw away (ie cells, automobile GPS, ect). Only GPS devices installed in things like military applications or aviation would receive a retrograde refit or all out replacement. Retrofitting your consumer GPS is not cost productive/feasible. Retrofitting GPS devices when its all said and done, I believe, would cost hundreds of millions of dollars.
 
BoogerBomb said:
Gps makers have fucked themselves now. We know that the system can be brought down extremely easy because they were too cheap to add a few cents worth of protection thereby rendering valuable wireless spectrum useless for forever.
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You do not understand the technical issues. Many people with RF backgrounds have pointed out the error of your analysis to countless other posters. At this point you need to stop posting and educate yourself.

LS' plan could not, would not, and will never work. Physics gets in the way. Period.
 
Daroller said:
You do not understand the technical issues. Many people with RF backgrounds have pointed out the error of your analysis to countless other posters. At this point you need to stop posting and educate yourself.

LS' plan could not, would not, and will never work. Physics gets in the way. Period.
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Im saying that they have exposed a weakness in GPS systems now. Whether its useful or not I don't know but an organization could render a ton of consumer GPS units useless with the right equipment.

And if this spectrum is not allowed to be used it should never have been licensed to anyone in the first place.
 
BoogerBomb said:
Im saying that they have exposed a weakness in GPS systems now. Whether its useful or not I don't know but an organization could render a ton of consumer GPS units useless with the right equipment.
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It's not something new, interference to radio signals by nearby powerful signals is a well known problem, that's arguably the main reason for the FCC existence in the first place. GPS can be jammed easily, but in the battlefield, a jammer becomes an easy target.

And if this spectrum is not allowed to be used it should never have been licensed to anyone in the first place.
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The LS license is meant for satellite communication, not terrestrial.
 
I remember reading about this when it first started. For once, a Government agency made the right decision. GPS is far too critical. Filters? Please. LightSquared should invested some of their money into common sense.

The LS license is meant for satellite communication, not terrestrial.
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End of thread.
 
Isn't this who Sprint is planning to roll their LTE out with? I wonder what's going to happen there.
 
BoogerBomb said:
Im saying that they have exposed a weakness in GPS systems now. Whether its useful or not I don't know but an organization could render a ton of consumer GPS units useless with the right equipment.
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Nothing new is exposed. This issue was well known in technical circles. Anyone who is versed in frequency management and GPS theory understands the strengths, weakness, and implications.

BoogerBomb said:
And if this spectrum is not allowed to be used it should never have been licensed to anyone in the first place.
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A spectrum licence is like a home owners association agreement. You don't have carte blanche to do with it as you like. Its filled with rules and regulations of left and right limits. Also, just like your drivers licence it can be revoked. A frequency licence allows the operator to operate their equipment within the specific parameters of the licence. Any deviation from the rule set requires the operator to reapply for a modification or an experimental licence with the appropriate agency up through the FCC.

Take a look at the NTIA Redbook (google it) for an idea of the spectrum bands and specific footnotes. The Redbook gives general guidance on the usage of spectrum. This book gives the general guidelines of what is and is not acceptable within specific bands.
 
yadnom said:
Isn't this who Sprint is planning to roll their LTE out with? I wonder what's going to happen there.
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They were planning to buy coverage from LS at the same time they deployed their own network. This would have gotten them more large metro areas short term; and more outer suburbs/rural areas long term since they and LS could split low density build out areas with only one deploying LTE in each.
 
LightSquared was a clear threat to the incumbent telecoms; it was a foregone conclusion that this "study" would not end well for them, not with $7 billion a year in net profits from the big two at stake.
 
fattypants said:
LightSquared was a clear threat to the incumbent telecoms; it was a foregone conclusion that this "study" would not end well for them, not with $7 billion a year in net profits from the big two at stake.
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Well you could be and probably are right that the big two may have had a hand in it somewhere.
 
fattypants said:
LightSquared was a clear threat to the incumbent telecoms; it was a foregone conclusion that this "study" would not end well for them, not with $7 billion a year in net profits from the big two at stake.
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Suuure..., that is why the AT&T purchase of T-Mobile was approved so fast. :rolleyes:
 
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