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FCC Bars Lightsquared From Using Airwaves

Unknown Lamer posted more than 2 years ago | from the lightsquared-disputes-laws-of-physics dept.

Wireless Networking 178

New submitter mc6809e writes with news that Lightsquared might have just been killed. From the article: "A proposed wireless broadband network that would provide voice and Internet service using airwaves once reserved for satellite-telephone transmissions should be shelved because it interferes with GPS technology, the Federal Communications Commission said Tuesday. The news appears to squash the near-term hopes for the network pushed by LightSquared, a Virginia company that is majority-owned by Philip Falcone, a New York hedge fund manager." LightSquared, naturally, continues to deny that the interference is real.

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178 comments

Sucks for Lightsquared (1, Interesting)

neokushan (932374) | more than 2 years ago | (#39043771)

It's my understanding* that Lightsquared's equipment was never the issue, but rather the GPS equipment that got interference were just poorly designed. If the GPS equipment was held to the standards it should have been, Lightsquared's equipment wouldn't have interfered. Yet Lightsquared are the ones being shafted, simply because GPS is "too important". Really, the FCC and/or the GPS equipment manufacturer should be the ones being penalised. FCC beucase it's their job to look after this sort of thing and the manufacturers for producing shoddy equipment.

*However note that I may be wrong, being an imperfect being and all that.

Re:Sucks for Lightsquared (0)

Anonymous Coward | more than 2 years ago | (#39043809)

Regardless of who is at fault, at this point, that's water under the bridge.

Re:Sucks for Lightsquared (1)

shentino (1139071) | more than 2 years ago | (#39044113)

It might not change whether LS gets to use the spectrum it paid for, but it means everything when determining who, if anyone, coughs up to LS to compensate for a blunder that may or may not have been theirs.

Re:Sucks for Lightsquared (1)

Anonymous Coward | more than 2 years ago | (#39044185)

my understanding is that they everyone is at fault:

gps manufacturer for going the cheapest route
lightsquared for purchasing a licence for satellite bandwidth and pushing unapproved high powered land based electromagnetic waves within the spectrum

fcc for applying and approval badge on cheapo gps receivers and not foretelling the problem; it's true they did not certify the tolerance to harmful frequencies but the non emission of them, but they're also the manager of the spectrum and should have put the rules up front in the first place.

Re:Sucks for Lightsquared (5, Informative)

Muad'Dave (255648) | more than 2 years ago | (#39044443)

Let's be clear - the FCC is not in the business of validating that any particular device is generally well-made or robustly-designed. Their one and only concern wrt to type acceptance is the RF _emissions_ of the device. They do not require testing of receivers for susceptibility to nearby carriers, intermodulation, desense or anything else, only their (in the case of a receiver, unintentional-) emissions. All not-otherwise licensed equipment carries the all-too familiar Part 15 warning [gpo.gov] about not causing and having to accept interference.

Re:Sucks for Lightsquared (5, Insightful)

Anon E. Muss (808473) | more than 2 years ago | (#39043817)

Really, the FCC and/or the GPS equipment manufacturer should be the ones being penalised.

As a practical matter, there's no way to do that. If you allow Lightspeed to operate, you penalize the USERS of the (allegedly) badly designed GPS devices. It does suck to be Lightspeed, because GPS really is much more important than them.

Re:Sucks for Lightsquared (4, Insightful)

smpoole7 (1467717) | more than 2 years ago | (#39044157)

> you penalize the USERS of the (allegedly) badly designed GPS devices

I maintain a 50,000 watt AM and two 100,000 watt FMs, and we get interference complaints all the time. The only fair rule for EVERYONE involved is to say, "as long as I'm following the terms of my license, and I'm SURE that my transmitter isn't putting out unwanted products, there's nothing I can do."

I'm friendly; I offer tips and suggest filters; I help if I can. But there's really not much I can do if they have a cheap radio. Am I "penalizing" them for buying a $20 table radio from WalMart? I don't think so.

You say "allegedly," but believe me, some of the cheap Chinese junk (albeit with good-sounding American brand names) being sold now isn't worth the money to crush and melt it. I would be astonished if the same isn't true of GPS equipment.

Re:Sucks for Lightsquared (5, Insightful)

Megane (129182) | more than 2 years ago | (#39044541)

And what if someone decided to operate a station on an adjacent frequency channel, with 10 megawatts of power? Or even half a channel over? (Rules? What rules? We just want a little variance in the rules!) Then suddenly people trying to receive your station get interference because the channel separation rules weren't designed for that kind of power on adjacent channels? The problem isn't "badly designed GPS devices", it's that this is a band which was allocated specifically for the purpose of satellite communication, which is by its very nature rather low-powered to begin with.

I'm almost surprised it took this long, except I'm sure there has been some ohbummer-related political interference going on behind the scenes. And it's probably still going on even now.

Re:Sucks for Lightsquared (-1)

Anonymous Coward | more than 2 years ago | (#39044791)

Be careful calling him "Ohbummer" around these parts... you might get modded down 15,355,793,900,149 points.

c wut i did thar?

Re:Sucks for Lightsquared (4, Informative)

farnz (625056) | more than 2 years ago | (#39044901)

And that's where the debate lies. LightSquared's license permits them two uses of the frequencies licensed:

  1. For satellite to earth communication, provided they ensure that the transmissions from the satellite do not leak out of their licensed bands.
  2. As a later waiver, made after the spectrum was initially licensed: For earth to earth and earth to space communication, provided that they ensure that their earth-based transmitters do not interfere with earth-based receivers designed to pick up satellite to earth transmissions in neighbouring bands.

LightSquared's argument is that they have met the second term of their license if they ensure that their earth-based transmitters do not leak out of their licensed bands, even if they interfere with licensed users of neighbouring bands; note that the FCC has been clear that one way to meet the second requirement is to replace receivers of the neighbouring bands with ones that cope with your interference, an option LS has rejected as impractical, as they cannot find affordable receivers that have both the GPS abilities of the receivers they're replacing and better rejection of LS's signals.

Re:Sucks for Lightsquared (0)

Anonymous Coward | more than 2 years ago | (#39045279)

Not sure about you, but vast sectors of the economy don't use your several thousand watt towers for navigation purposes.

I see the argument you are making, however I wouldn't compare standard broadcast towers to GPS broadcast satellites. Each has it's own very different purpose, scope, and design.

Re:Sucks for Lightsquared (1)

Attila Dimedici (1036002) | more than 2 years ago | (#39045455)

The thing is that terms of Lightspeed's license is that they demonstrate that they do not interfere with those GPS devices.
If those complaints came from people who had bought those radios before you got those licenses and your license stipulated that you not interfere with their reception of other radio stations then your situation would be different.

Re:Sucks for Lightsquared (0)

Tharsman (1364603) | more than 2 years ago | (#39044297)

How about forcing manufacturers of faulty GPS equipment to replace the units? It was THEM selling units they know were defective because "no one" used the neighboring spectrum.

Re:Sucks for Lightsquared (5, Informative)

davros74 (194914) | more than 2 years ago | (#39044383)

The GPS units are not faulty. The spectrum they use are reserved for SATELLITE reception, not terrestrial broadcast. The signal levels received are so incredibly weak, that it is quite difficult, certainly not cheap, to build filters to filter out a nearby signal that is several order of magnitude stronger than yours. The spectrum was reserved, by the FCC, such that the neighboring spectrum would be like weak signals, which makes building receivers with high sensitivity possible and affordable.

I am sorry, but it was lightspeed who deceptively came in, got the spectrum, then changed from a mostly satellite based service (which would have been fine in that spectrum), to one consisting of tens of thousands of TERRESTRIAL transmitters in the L1 band, that simply overpower the nearby satellite downlink signals.

You just cannot build a high sensitivity receiver with a filter strong enough to filter out that kind of interference.

The FCC never should have granted them a go ahead in that frequency band in the first place.

Re:Sucks for Lightsquared (5, Informative)

davros74 (194914) | more than 2 years ago | (#39044509)

I would also point out that the frequency band GPS and satellite signals are in are much cheaper than terrestrial frequencies. As such, Lightspeed abused a (poorly conceived) FCC ruling for filling in poor reception areas with local ground based transmitters, to take cheap satellite spectrum, and repurpose it for a very large and high-powered terrestrial network, without paying similar licensing fees other terrestrial providers have to pay for their spectrum.

The whole loophole started by the FCC allowing ground based transmitters in the L1 band, but the intent was to supplement poor reception of satellite signals with some ground based ones. They never intended it to be repurposed for massive scale and high powered ground transmitters everywhere.

The laws of physics don't work well with you here when you have very weak signals from space competing with local, very strong signals on the ground, and only a few MHz apart in the GHz range. That was the original reason satellite based signals have their OWN spectrum. While it stinks for Lightspeed, they should know they never should have really gotten that spectrum from the FCC in the first place. The FCC dropped the ball on this one, but perhaps that's not too surprising how much corporations can buy influence in Washington these days.

Re:Sucks for Lightsquared (0)

Anonymous Coward | more than 2 years ago | (#39044435)

Just make sure you heavily publicize that the users have the right to send back their defective units for replacements.

Re:Sucks for Lightsquared (5, Informative)

ZaMoose (24734) | more than 2 years ago | (#39043825)

The last time /. discussed this, it was pointed out that the spectrum L^2 was aiming for was intended for low-power satellite signals and was never intended to be used for (relatively) powerful ground stations. They were essentially trying to buy spectrum on-the-cheap and then repurpose it in a way that was virtually guaranteed to interfere with adjacent spectrum. So, while GPS devices could certainly be better-designed, this was more an incident of L^2 trying to abuse the system.

Physics, alas, makes for a harsh mistress.

Re:Sucks for Lightsquared (2, Funny)

Anonymous Coward | more than 2 years ago | (#39044057)

Physics, alas, makes for a harsh mistress.

Yeah, but that's because Physics is a old, hairy dude.

Re:Sucks for Lightsquared (1)

poetmatt (793785) | more than 2 years ago | (#39044619)

Yes, lightsquared was taking advantage of the system. Absolutely. While it's not ethical, that kind of crap is pretty much legal in the states.

so it becomes a competitive question here - why aren't GPS devices better designed? why isn't L2 trying to avoid neighboring spectrum? etc. It's no longer "L2's fault" but both - to imply L2 when you acknowledge both have an issue (manufacturing to specs should be regulated by the FCC and isn't, yet FCC is regulating Lightsquared) is to focus on one side of the issue.

Regardless of lightsquared, we should be hearing an excessively large amount of things being done by the FCC to regulate GPS. Their lack of doing anything is more telling than lightsquared or the GPS mfr's themselves.

Re:Sucks for Lightsquared (4, Informative)

Zcar (756484) | more than 2 years ago | (#39044759)

so it becomes a competitive question here - why aren't GPS devices better designed?

Because they were engineered with the constraints of their band in mind. If the rules of the band are such that you don't need to worry about a powerful signal on an adjacent frequency, designing a filter to deal with such an adjacent signal is unnecessary expense.

Re:Sucks for Lightsquared (4, Insightful)

Deadstick (535032) | more than 2 years ago | (#39044917)

L2 made one big mistake. Stepping on a lot of toes? No biggie, happens all the time. Stepping on toes that are in a building with five sides? Might want to think about that.

Re:Sucks for Lightsquared (-1)

AikonMGB (1013995) | more than 2 years ago | (#39043849)

This is my understanding as well, and appears to be precisely the complaint that LightSquared is making. Based on this, it is my opinion that the FCC is at fault here -- they should never have granted LightSquared the license for these frequencies in the first place if they did not intend to honour said license.

Re:Sucks for Lightsquared (1)

Anonymous Coward | more than 2 years ago | (#39044171)

You mean someone in the Government was incompetent and/or duplicitous? No, how can that be!

Re:Sucks for Lightsquared (3, Informative)

yourmommycalled (2280728) | more than 2 years ago | (#39044941)

No the FCC isn't at fault. the FCC licensed the spectrum to American Mobile Satellite Corporation and later as Mobile Satellite Ventures after a merger between Motient Corporation and TMI Communications. It was most recently known as Skyterra, a company that provided mobile satellite communications services. There was also a cooperation agreement between Inmarsat and LightSquared. Had LightSquared continued to used the spectrum as it was licensed for this whole mess would have never occurred. The problem is LightSquared demanded a waiver from the FCC to use the spectrum for purposes the spectrum was not allocated for AFTER purchasing the companies who owned the spectrum for satellite-to-ground communications. Blaming the FCC in this case is like blaming Texas Instruments because their TI-89 calculator does not work very well as a ruler.

Re:Sucks for Lightsquared (2)

rudy_wayne (414635) | more than 2 years ago | (#39043865)

According to this article: [sail-world.com]

One of the MSS (mobile satellite service) bands involved is just below the GPS L1 band used by commercial GPS units. The FCC has authorized use of this band for terrestrial cellular services since 2003 .

Now there is some dispute about details of the early FCC decisions and how many base stations were allowed under them, but it is clear that base stations were allowed next to the GPS band since 2003 and that the civil GPS supplier community paid little attention to the fact that GPS would be having a new neighbor with much stronger signals in some places than the original MSS signals.

The GPS industry has not pressed the filter manufacturers for the latest technology as the cellular systems in nearby bands have. As a result many GPS receivers have a lingering vulnerability to strong adjacent band signals that results from GPS manufacturers ignoring policy changes made in the US almost a decade ago!

Re:Sucks for Lightsquared (4, Informative)

tixxit (1107127) | more than 2 years ago | (#39044347)

According to the actual 2003 decision by the FCC:

Today we decide to permit flexibility in the delivery of communications by Mobile Satellite Service (MSS) providers [cut]. Specifically, we permit MSS licensees to integrate ancillary terrestrial components (ATCs) into their MSS networks

...

We will authorize MSS ATC subject to conditions that ensure that the added terrestrial component remains ancillary to the principal MSS offering. We do not intend, nor will we permit, the terrestrial component to become a stand-alone service.

That is, the decision was to let those offering mobile satellite services the ability to enhance their networks. This guy wanted to create a stand-alone cell phone network, which was explicitly not permitted in the 2003 decision.

Re:Sucks for Lightsquared (2)

foo1752 (555890) | more than 2 years ago | (#39043875)

I know that it is probably too much to ask, but if you had read some of the letter from the NTIA, they specifically mention that there are no performance standards for GPS equipment to be compared against. That is, no one ever told manufacturers of GPS equipment that they had to deal with so much interference in neighboring frequency bands. The result of this may be that some standards are developed, but that does nothing for the huge installed base of GPS receivers.

Re:Sucks for Lightsquared (5, Informative)

FireFury03 (653718) | more than 2 years ago | (#39043887)

It's my understanding* that Lightsquared's equipment was never the issue, but rather the GPS equipment that got interference were just poorly designed. If the GPS equipment was held to the standards it should have been, Lightsquared's equipment wouldn't have interfered. Yet Lightsquared are the ones being shafted, simply because GPS is "too important".

That's not quite true. LS basically bought up a *satellite* band and tried to repurpose it for ground communications. It was then discovered that doing this caused some GPS equipment to malfunction. Whether or not you consider this GPS equipment to be "poorly designed", the fact remains that it was working absolutely fine for decades and LS's attempts to repurpose the ajacent band causes it to stop working. Expecting millions of GPS users to upgrade their GPS receivers just because LS wants to repurpose an existing band for a new use is ridiculous. On the other hand, if LS wants to buy shiny new GPS receivers for all these end-users...

So no, LS isn't "being shafted" - they purchased a satellite band with the intention of using it for ground communications, rather than its existing use, badgered the FCC into letting them repurpose it and then cried when it was found that this repurposing wasn't compatable with millions of existing devices.

Re:Sucks for Lightsquared (0)

alanshot (541117) | more than 2 years ago | (#39044163)

...Expecting millions of GPS users to upgrade their GPS receivers just because LS wants to repurpose an existing band for a new use is ridiculous...

Sure they can; they already did that. How do you think this spectrum came open in the first place? They forced consumers that were still using old TVs to receive analog TV signals to buy new equipment.

I really dont see this requirement as anything different. The only difference I see is the majority of the last lot of impacted consumers were mainly low income that couldnt really fight the change, whereas this class of impacted consumers are likely to be more well off and connected as they obviously have the disposable income to buy shiny gizmos like GPS units, etc.

Re:Sucks for Lightsquared (5, Informative)

msauve (701917) | more than 2 years ago | (#39044269)

How do you think this spectrum came open in the first place? They forced consumers that were still using old TVs to receive analog TV signals to buy new equipment.

Wow. You couldn't be more confused. Analog TV operated in 54-88 MHz, 174-216 MHz (VHF), and 470-890 MHz (UHF) bands. GPS is up above 1 GHz, 1.57542 GHz (L1 signal) and 1.2276 GHz (L2 signal) being the primary signals. The frequencies that Lightsquared wants to use have nothing to do with the any spectrum which was previously used for TV.

Re:Sucks for Lightsquared (2)

tepples (727027) | more than 2 years ago | (#39045359)

I think the confusion came from the fact that the ATSC transition let the FCC sell the top half of UHF to cell phone providers.

Re:Sucks for Lightsquared (1)

Rakishi (759894) | more than 2 years ago | (#39044305)

I'm guessing you were asleep when all the coupons for free digital tv receivers were given out, god that must have been a nice nap you had.

Plus paying $30 for a converter (and often $0) is very different than paying $20000 for a new GPS (yes, the aircraft ones cost around that much).

Re:Sucks for Lightsquared (1)

davros74 (194914) | more than 2 years ago | (#39044537)

The military versions cost even more. Want your car-based GPS to cost more than your mortgage?

Re:Sucks for Lightsquared (0)

Anonymous Coward | more than 2 years ago | (#39044323)

Government provided a $20 voucher to purchase a digital tuner to work with existing TV sets. The digital tuners cost $20, and very few people needed them.

Comparing that situation with making a lot of people buy new GPS units is staggeringly stupid on your part.

Re:Sucks for Lightsquared (1)

Megane (129182) | more than 2 years ago | (#39044605)

This doesn't involve any band previously used by television.

Troll harder.

Re:Sucks for Lightsquared (0)

Anonymous Coward | more than 2 years ago | (#39044497)

You mean someone at Lightsquared was incompetent and/or duplicitous? No, how can that be!

Re:Sucks for Lightsquared (1)

Xpendable (1605485) | more than 2 years ago | (#39045251)

I'm a private pilot. FAA certified panel-mounted GPS systems for airplanes can cost anywhere betwee $2,000 on up to $20,000+. Just saying.

Re:Sucks for Lightsquared (5, Informative)

heypete (60671) | more than 2 years ago | (#39043899)

GPS receivers (and the filters in their electronics) were built with the assumption that neighboring frequencies would be used by other space-to-ground uses, and thus would have comparable signal strengths (that is, very low).

Having ground-based stations blasting out signals that are brazillions of times more powerful than the weak space-to-ground signals on adjacent frequencies would overwhelm the relatively weak signal from GPS. Filters that can allow the weak GPS signals through while blocking out the immensely more powerful signals on neighboring frequencies would be bulky and expensive. Devices not equipped with those specialized filters (that is, essentially every GPS receiver ever made) would be screwed.

I'm sure that if LightSquared wanted to use the frequencies they acquired for space-to-ground uses, the FCC would have very little trouble with it and the potential for interference with GPS would be essentially nil. Instead, LightSquared purchased (leased? I'm nowhere near an expert on this kind of thing.) these frequencies at a cheap price due to their being intended for space-to-ground use and was trying to change their classification to use them for ground-based transmitters (thus saving LightSquared tons of money acquiring spectrum). They gambled big and (rightfully) lost.

Reliable GPS service is more important than the communication network LightSquared proposed, particularly in regards to safe navigation for aircraft and vessels.

Re:Sucks for Lightsquared (3, Interesting)

kaiser423 (828989) | more than 2 years ago | (#39044889)

Don't forget that in response to LightSquared, DirectTV and pretty much every single company that owns satellite to ground spectrum was filing for similar waivers essentially re-purposing satellite communications to ground-base communications and creating the potential for satellite apocalypse as it becomes thousands of times harder to communicate with *all* satellites, effecting weather, hurricane, tsunami forecasting, early warning systems, satTV and radio, etc, etc. GPS/LightSquared was the proxy war for all of these other providers and it's very, very good that LightSquared did not win.

Re:Sucks for Lightsquared (4, Informative)

msauve (701917) | more than 2 years ago | (#39043901)

Not quite. The spectrum adjacent to GPS frequencies was authorized for for use with other satellite services, which obviously have a very low signal level. GPS receivers were designed with that in mind. That's not unreasonable, in the real world there's no such thing as a perfect filter with vertical skirts.

Lightsquared "bought" this spectrum, much cheaper than similar spectrum allocated for terrestrial use. They then fast tracked a petition through the FCC to get authorized to use that spectrum terrestrially. The problem is, that produces much stronger signals than GPS receivers were designed to deal with.

If Lightsquared were to use the spectrum as originally intended, there would be no issue. Instead, they want to have their cake, and eat it too, by paying for relatively low cost satellite spectrum, but using it for terrestrial transmitters.

Re:Sucks for Lightsquared (0)

Anonymous Coward | more than 2 years ago | (#39043909)

This would be the drivel that LS has been spouting all along. GPS equipment is not "poorly designed." LS purchased a spectrum that was labeled by the FCC for satellite communications (satellites far away!) Then, they decided they wanted to use this spectrum for terrestrial broadcast (earth closer!) The end fact of all of this is that your filter has to be good enough to filter out a signal that is MILLIONS of times more powerful than the GPS signal, in an adjacent band.

The real story here is that LS purchased a cheap spectrum, and want to convert it into a valuable one, and they're putting out all sorts of BS to sway public opinion. And the public, being without knowledge in the science and engineering, buys every filthy word.

Re:Sucks for Lightsquared (4, Informative)

worip (1463581) | more than 2 years ago | (#39043927)

Actually, the spectrum was never intended for terrestrial use at all. Lightsquared applied for an exemption to apply the spectrum for terrestrial use, but they had to prove that it did not intefere with GPS. Most RF engineers would have told you that they where doomed from the start to fail, as the physics does not allow you to do this. All RF equipment have to contend with a thing call adjacent channel rejection - i.e. whilst tuned to its own channel a device must reject inteference from channels adjacent to its own by using a bandpass filter. Bandpass filters are not perfect (i.e. it is not a brickwall) and some interference always leaks through. The specific issue here is that the terrestrial signal would have been so large compared to the signal received from the GPS sattelite that the bandpass filters would have been unable to suppress the signal in the adjacent channel. This is akin to someone shouting in your ear, while you are trying to listing to someone whispering 20meters away.

Re:Sucks for Lightsquared (0)

shentino (1139071) | more than 2 years ago | (#39044167)

Where GPS is a politically entrenched industry with the FCC in their pockets, which gives them a long leash to hog all the spectral elbow room they can get away with.

GPS saw nothing but tumbleweeds, so it let itself go with lax filtering, and now it's "too big to fail" when LS shows up trying to move in next door.

Re:Sucks for Lightsquared (1)

DrgnDancer (137700) | more than 2 years ago | (#39044455)

Actually GPS knew there was a regulatory requirement for "nothing but tumbleweeds" and designed their systems according to said regulatory requirement. The adjacent spectrum was also marked for satellite transmission. There was no reason for GPS manufacturers to assume that suddenly there would be powerful terrestrial transmitters sitting next door, as they were told the adjacent frequency bands would be used for similar low power signals.

Imagine you need to build a very loud factory. You go buy a parcel of land zoned for manufacturing, surrounded by other parcels of land also zones for manufacturing. You don't use a lot of sound dampening material, because, hey, he other loud factory owners in the are don't care much. You run your factory for a decade when a developer buys the parcel of land next door. Suddenly the developer is trying to get teh land rezoned as residential and they and their customers are complaining that your factory is too loud. Should you, sitting on your manufacturing zone land, following the rules established for property zoned the way yours is, suddenly have to install a bunch of filters because some dude bought a bunch of cheap land is is trying an end run around the regulations that made it cheap in the first place?

Politics? Huh? (1)

sirwired (27582) | more than 2 years ago | (#39044699)

What does this have to do with politics? GPS operates in a satellite band, and the surrounding traffic is also supposed to be satellite. It is perfectly proper for GPS makers to design their filters around their expectations for surrounding traffic. It would have just been needless complexity and expense for zero end-user benefit to design them tighter.

If I build my house in the middle of nowhere surrounded by farmland, peace, and quiet, you can damn sure I'm going to protest when somebody tries to re-zone the land next door to be a shotgun range. I'm not going to be too impressed when the shotgun club guys tell me to just add more insulation to my house.

Re:Sucks for Lightsquared (1)

DeadCatX2 (950953) | more than 2 years ago | (#39044717)

Some engineer did their homework. They decided to create a filter with the necessary -dB/octave roll-off needed to deal with the signals that could be expected in the real world.

In the real world, signals of the power that LightSquared wants to use were illegal at the time the GPS device was manufactured. As in, violators go to federal pound-me-in-the-ass prison.

So how, exactly, are their filters "lax", if they were designed to deal with the maximum power signals that were legal at the time of design?

Re:Sucks for Lightsquared (0)

Anonymous Coward | more than 2 years ago | (#39043961)

Exactly! L^2 is being penalized due to the poor reception design of GPS receivers on the market. It would be like me designing an FM radio receiver that was 10 mHz wide because the only radio stations in my area were farther than that apart, having a new station licensed 5 mHz away from another causing reception issues on my radio, then I wine to the FCC for allowing that new station to be licensed, and then that stations license being yanked.

Also, GPS was never designed for any type of "mission critical" application. It's embarrassing that the individuals against L^2 are holding "public safety" hostage, when the issue is due to cheap GPS design in search of higher profits.

Re:Sucks for Lightsquared (2)

davros74 (194914) | more than 2 years ago | (#39044691)

You're missing a big point. Adjacent carriers in the FM band are all transmitting at comparatively the same SIGNAL STRENGTH. As such, filter design is not too hard to do. Filters are not perfect, and some adjacent channels will always leak through. If the adjacent channels are attenuated enough, you get good reception. If all the signals start out at about the same signal strength this works ok.

But a ground based transmitter adjacent to a weak satellite downlink? You're starting with the two signals many many orders of magnitudes different in signal strength (millions even). Even if you reduce the adjacent channel interference, a signal that strong, even if 0.1% of it gets through the filter, will still swamp out your intended signal.

Ever tried listening to someone whisper to you while standing next to a jet engine? Earplugs do not really help, do they?

Re:Sucks for Lightsquared (1)

DeadCatX2 (950953) | more than 2 years ago | (#39044797)

Argh! Where do I start?

For one thing, you mean MHz. With a capital M. A lower case m would be milli. FM stations are not separated by millihertz.

For two, it is NOTHING like that. It's more like designing an FM radio receiver, and then someone comes in and starts blasting AM all over your frequency band.

Remember that when the GPS devices were designed and manufactured, signals of the power that LightSquared wants to use were ILLEGAL. As in, violators go to federal pound-me-in-the-ass prison.

Do you really want to punish engineers for doing their homework and creating cost-effective designs intended for practical applications in the real world according to existing laws and regulations?

Re:Sucks for Lightsquared (4, Insightful)

darkstar949 (697933) | more than 2 years ago | (#39043963)

This has been coming up over on Ars Technica for awhile now and the explanation isn't so much that the GPS equipment is poorly designed but rather that Lighsquared is trying to use the spectrum in a way that it was not licensed to do so in. In short, the spectrum that they licensed is for low power satellite communications (i.e. GPS) and they want to use the same spectrum but to increase the power at which they broadcast it up to normal terrestrial levels. At that point the common analogy is that it is like trying to tell the color of a flashlight from a couple miles away: once you spot it you can tell when the color changes, but if someone comes along and places a high power search light next to it, the flashlight will drown out by the power of the other light source.

Also, don't forget that radio signals aren't prefect pathways either and you can be broadcasting on one frequency and have it bleed over into another frequency. This is why radio stations and television channels are allocated in such a way that they aren't directly next to each other (think radio channel 100 and 100.1).

So in summary, this isn't an equipment problem but a physics problem: making the equipment better isn't going to help the fact that the signal would be drown out if Lighsquared were to broadcast on a satellite channel at terrestrial power levels.

Re:Sucks for Lightsquared (4, Insightful)

fuzzyfuzzyfungus (1223518) | more than 2 years ago | (#39044179)

One wonders if Lightsquared thought that they had a good chance of pulling this off, either through technological optimism or confidence in their legal team(For whatever reason "Rural broadband!!!" appears to be the FCC's root password) or if this was some sort of long-odds/high-rewards gamble by the hedge fund chap...

On the one hand, being able to convert a swath of satellite-to-ground spectrum into ground-ground spectrum would be crazy valuable, and likely result in some very nice returns. On the other, trying to go up against the now-firmly-entrenched users of GPS(ie. almost everybody) is a risky move indeed.

Did they miscalculate the odds, or were they happy to take very bad odds for the possibility of extremely high returns?

Re:Sucks for Lightsquared (5, Insightful)

hamburger lady (218108) | more than 2 years ago | (#39044205)

it's more like getting a permit to open a bar next door to an observatory but the city strictly requires you to keep your outdoor lighting to a minimum so as not to disturb the telescope next door. yet you still put up a huge neon sign and searchlight and when the observatory complains that your light pollution has ruined its ability to gather data, you say 'it's not my fault your telescope sucks'.

I wish I could mod you up (0)

DeadCatX2 (950953) | more than 2 years ago | (#39044915)

This bar/"telescope sucks" analogy is perhaps one of the best ones I've heard yet. Too bad I already made replies and I can't mod you up myself.

Re:Sucks for Lightsquared (1)

vlm (69642) | more than 2 years ago | (#39044023)

rather the GPS equipment that got interference were just poorly designed. If the GPS equipment was held to the standards it should have been,

Blatantly false. Ask your closest EE to run the numbers. The numbers are utterly insane. You need something like multiple superconducting resonant cavities to pull this off. IF you were willing to ten-tuple the size of your cellphone and include a liquid helium fill port and dewar then it'll work, just fine. At least the liq He dewar will stop the phone from physically heating up as you talk on it.

Also they were very well designed to operate within and around a satellite to ground transmission band. Playing legal games decades later and adding high powered ground transmitters is a massive legal failure, not a design failure. This is a FCC has egg on its face moment, as in, don't they have any technically skilled people in the commission anymore?

Re:Sucks for Lightsquared (2)

fuzzyfuzzyfungus (1223518) | more than 2 years ago | (#39044069)

For better or worse, it is generally the case that Legacy Systems Win.

Outside of some limited consumer markets, or the occasional dramatic(and generally traumatic) forklift upgrade of some gigantic institutional system(usually still leaves a screen-scraper connected to the old system that everybody politely doesn't talk about hidden somewhere...), the clout of Stuff That Already Works is enormous compared to that of Stuff that Might Be Cool.

If it were merely a matter of forcing Garmin into a class action and giving all their past customers a shiny nickel to spend on new Garmin products, it might have worked. GPS, though, is firmly embedded in all sorts of slow-turnover, expensive, capital equipment and infrastructure. No way is it getting displaced in the near term...

Re:Sucks for Lightsquared (1)

RoboRay (735839) | more than 2 years ago | (#39044279)

Your understanding is not correct. Had Lightsquared sought to use the satellite-only restricted band they bought for a satellite-based system, they would have been fine. Instead, they bought use of a satellite-only restricted band (which was cheap, because it's not useable for terrestrial-based transmitters, so nobody else really wanted it) and wanted to use it for a terrestrial-based system.

ALL RF transmissions affect nearby bands, not just those the transmitter is intended to use. While it's trivial for a system like GPS (which is designed to receive very weak signals from distant satellites) to filter out very weak signals on adjacent bands, it's extremely difficult (if not impossible) for such a system to filter out the strong signals from nearby transmitters on adjacent bands which are completely overwhelming the weak signals it's trying to detect.

This is WHY the bands adjacent to GPS are restricted to satellite-based transmitters.

The laws of physics and their own failure to understand them is what screwed Lightsquared.

Re:Sucks for Lightsquared (1)

yourmommycalled (2280728) | more than 2 years ago | (#39044835)

From the very beginning it was LightSquared's basic design and equipment that was at fault. GPS receivers are/were properly designed and constructed. Even the cheapest GPS equipment exceeds the standards for rejecting interference. LightSquared knew in advance the spectrum they were buying was not licensed for ground-to-ground communications only satellite-to-ground communications. Even with just freshman level physics you should be able to understand how LightSquared's ground-to-ground signal strength (typically 70 dBm) will over power and interfere with far weaker GPS signals from space (typically 150 to 130 dBm at ground level). The GPS receivers specs never intended to deal with this situation. LightSquared tried to use the FCC regulatory process to deny basic physics. You cannot deny basic physics just because you want to make money. The problem is yet another clueless MBA clown thinks that because he has money he can do what ever he wants

Re:Sucks for Lightsquared (0)

Anonymous Coward | more than 2 years ago | (#39045265)

It's my understanding* that Lightsquared's equipment was never the issue, but rather the GPS equipment that got interference were just poorly designed.

Except that's the spin by Lightsquared and is not true in the least. The point of contention is that older equipment, which is properly deisgned, was simply not designed to deal with the interference created by their technology. At the time the older equipment was created, such purposeful and directed interference not only didn't exist, it was illegal. Notice the equipment works perfectly well without their interference. Given replacement equipment can easily cost over $15,000 per unit, its not a fair requirement to force owners to upgrade to newer, more resilent equipment just so they can start making money. Now if they want to pay for everyon's equipment to be upgraded, I don't think you'll find opposiition, but I doubt they are willing to pay for the estimated billion dollars required to do so.

Sorry, but blaming well designed equipment for their interference is 100% marketing bullshit.

Re:Sucks for Lightsquared (1)

hairyfeet (841228) | more than 2 years ago | (#39045355)

You seem to be missing the point that the ONLY reason LS was able to get this chunk of the spectrum in the first places was for SAT communications NOT ground, and if LS would have stuck to that frankly there wouldn't be a problem. Its not the fault of the FCC that LS decided they couldn't make a go of it in the business plan they had originally agreed to, they should have to sell the spectrum they bought to someone else or stick with the original agreement. Frankly it doesn't matter what the GPS OEMs did or didn't do, this spectrum was sold with limitations attached and without those limitations would have sold for probably a lot more.

In my mind this is no different than those shady dealers that will pick up Seagate drives designed for video surveillance and because of the flood raising the price of drives trying to pawn them off as regular HDDs. They were sold cheaper than regular drives FOR A REASON and that was because they simply weren't built for the same use case but for stop and go data dumping not running an OS. Same here they got a cheaper deal on something that had been allocated for one use and some hedge fund manager thought he could pull an end run. Well too bad, you read the contract, you rolled the dice, you lost.

Re:Sucks for Lightsquared (1)

rally2xs (1093023) | more than 2 years ago | (#39045539)

Nobody should be penalized. The GPS receivers were built to the standards that existed at their manufacture, which did not include aggressive adjacent channel interference. That was supposed to be satphones, which would have been a few watts from a handheld transmitter, that would not likely have interfered with most GPS receivers. But the Lightsquared transmitters were not low power, and would have overwhelmed the GPS receivers built to reject low power signals from sat phones.

Can you see making virtually all of the GPS receivers in existence obsolete? The one in my car is part of an entertainment console that was right around $2700 installed. The GPS handheld that I own was around $400. The GPS receivers for my laptop mapping program would also have to be replaced, and cost about $10 as they were offered from Delorme. Think they'll be able to build something that rejects a high power adjacent channel signal for $10? I'd suspect not.

Its good to see the FCC doing the right thing for the American people this time, rather than the right thing for some big business.

GPS was here first, end of story. (3, Insightful)

Anonymous Coward | more than 2 years ago | (#39043803)

The FCC made a good and wise decision in this situation.

It is unrealistic to expect the desires of a company which wants
only to make money should override the safety of a public
which depends increasingly on GPS.

Look for Iran to implement this technology (5, Funny)

Tekfactory (937086) | more than 2 years ago | (#39043859)

I mean if it gives you broadband, voice and blocks GPS guided missiles, what more could you want?

Re:Look for Iran to implement this technology (0)

Anonymous Coward | more than 2 years ago | (#39044099)

I have a feeling that GPS guided missiles are capable of filtering interference at least as well as the free cell phone with two-year contract (mentioned in the Ars article). Besides, laser guided is where it's at now. I, for one, really want to try out those laser guided bullets I read about a week or so ago. Might not be a lightsaber but it's still pretty awesome.

Re:Look for Iran to implement this technology (1)

blueg3 (192743) | more than 2 years ago | (#39044173)

In addition, GPS-guided missiles are designed to still function well under loss of GPS signal. The military knows full well how brittle GPS can be.

Massive simplification (4, Informative)

vlm (69642) | more than 2 years ago | (#39043935)

"A proposed wireless broadband network that would provide voice and Internet service using airwaves once reserved for satellite-telephone transmissions should be shelved because it interferes with GPS technology, the Federal Communications Commission said Tuesday

That's a massive simplification. They sell mobile satellite internet, and have done so for a long time, and will do so into the indeterminate future, this has nothing to do with that.

The LS idea was to provide a backend carrier to local on ground cellular providers for internet traffic. Same as your off the shelf 3G service you now "enjoy" but instead of your greedy provider paying AT&T (or whoever) for fiber to the cell phone tower, they'd use the satellite service.

Except... they didn't have an allocation for their ground network. Hmm. What if we reuse the satellite freqs, yeah that'll work. Well, except that the would ruin/destroy/eliminate the possibility of anyone on the ground hearing the satellites without a huge dish or technically impossible filtering. OK no problemo we'll dump all our satellite customers and focus on the ground guys, and use the marketing for satellite "as if" we're not a ground 3G provider. Whoops that'll kill all the adjacent satellite services too. Oh Oh, GPS is adjacent.

Well, so much for that bad idea.

Note there is no reason that instead of paying AT&T for fiber to a cell tower in the middle of nowhere, LS can't provide slow and high latency service RIGHT NOW to that cell tower... this FCC bar only stops them from setting up their own tower and using the satellite freqs to set up something like a 3G service.

The standard /. car analogy is this is kind of like getting rid of the SUV exception where hyper obese ultra low MPG passenger cars are permitted under the legal fiction they are classified as trucks not cars. That takes care of the analogy "why the F are they installing 100 watt ground transmitters on an allocation for satellite transmitters only?". Or maybe a better analogy is LS thought it would be fun to build a network of hydrogen fueling stations, and figured no one would have any problem if they used an off the shelf gasoline filling nozzle instead of a technically correct solution that would not result in an infinite number of burnout fires. That takes care of the analogy "why the F are they installing 100 watt ground transmitters right next to satellite receivers and even daydreaming that won't knock out the receivers".

Don't screw with the big telcoms (0)

elrous0 (869638) | more than 2 years ago | (#39043945)

Wasn't one of the stated goals of Lightsquared to help little companies compete with the big telcoms on the wireless broadband and mobile phone service fronts? If that's the case, I suspect way more was involved here than just GPS interference.

Crooked Wall St del-boy getting what he deserves (1)

benjfowler (239527) | more than 2 years ago | (#39043981)

Why am I surprised that some rich Wall St prick thinks like all other spoilt Wall St pricks, and thinks that they are exempt from the rules that everyone else is subjected to, and try and get one over everyone else so he can get even more obscenely rich than he is.

I hope that prick Philip Falcone gets bankrupted for his hubris, and learns some morals and a little humility.

Adjacent channel interference (0)

DomHawken (1335311) | more than 2 years ago | (#39044003)

This ruling basically renders Lightsquared dead in the water - they will no doubt continue to challenge the FCC but it's extremely unlikely that it will be overturned. There's $14 billion invested from Harbinger Capital at stake, which I can imagine is a large chunk of funds and could also bring them down in the fallout.

Whats interesting here is that this part of the spectrum has been licensed to them (and presumably paid for), yet is unusable because up to 75% of GPS receivers, that use frequencies just up the range, next door to Lightsquared's spectrum, have insufficient adjacent channel rejection and will be jammed. This is not a problem of Lightsquared's making, it's because the GPS's have been built to poor design standards and allowed onto the market and into circulation.

Presumably there is therefore an agency that can be sued for allowing the spectrum to be compromised in this way? $14B is a lot of money...

Re:Adjacent channel interference (2)

Rakishi (759894) | more than 2 years ago | (#39044391)

Whats interesting here is that this part of the spectrum has been licensed to them (and presumably paid for), yet is unusable because up to 75% of GPS receivers, that use frequencies just up the range, next door to Lightsquared's spectrum, have insufficient adjacent channel rejection and will be jammed. This is not a problem of Lightsquared's making, it's because the GPS's have been built to poor design standards and allowed onto the market and into circulation.

So if I tell you that we're going to play hockey and you bring proper protection then I shoot you with a shotgun it's your fault for not bringing a bulletproof vest?

Those frequencies were supposed to be for satellite transmissions, GPS worked perfectly fine under that assumption. Lightsquared would have paid a lot more for frequencies that were allocated for ground transmissions. They didn't. They tried to cheat the system and rightfully got burned.

Furthermore as others have pointed out there's a physical limit on what can be filtered out and a ground transmitter would have caused interference no matter what type of GPS device or filtering you had.

It's too bad (0)

Karmashock (2415832) | more than 2 years ago | (#39044013)

We do need to utilize these spectrums.

I think what we have here is another example of why business and politics don't mix. Falcone tried to shmooze his way through the system by budding up to the administration and it backfired by creating enemies.

I don't know if his tech is causing a problem or if it's all a big conspiracy to shut him down. It doesn't matter. He assumed he would pass inspection before the fact because he knew all the right people. He had made no preparation for rejection and that was stupid. Had he done what everyone else does... he would have waited until he tech was approved before making any big expenses.

Smart businesses make donations to both parties and focuses on avoiding conflict rather then making special friends. Friends come with their enemies and Obama has lots.

The only thing he can do is try again either with modified technology so he can pass inspection or try a different spectrum. Sucks... but it's that or give up.

Swatch time (0)

Anonymous Coward | more than 2 years ago | (#39044019)

It's @641 beats mother fuckers.

LightSquared isn't the victim! (5, Insightful)

tsj5j (1159013) | more than 2 years ago | (#39044037)

The article seems to gloss over the most critical point that breaks this deal, painting LightSquared as a victim in the process:

LightSquared's spectrum (which was bought from another company) was for SATELLITE transmissions, not TERRESTRIAL.
Satellite spectrums are much cheaper, but can't be used for terrestrial transmissions.
LightSquared is in fact trying to cheap out by using a cheaper spectrum.

Analogy:
LightSquared tried to buy a plot of cheap residential land to start a chemical/manufacturing plant, which affects nearby residents.
They should have bought a piece of commercial land that supports their requirements.

More technically:
Satellite signals are weak as they are sent from huge distances from satellites with limited power. To receive these signals, the receivers must be tuned to be sensitive to these signals. If LightSquare were to transmit terrestrially from the bordering spectrum (to pass through walls and what-have-you), the transmitted strength will be thousands of times stronger than the GPS signals, invariably causing interference with GPS signals. Even if GPSes are built with a filter (which they shouldn't need to, the nearby spectrums should also be weak signals!), it would be prohibitively expensive/unfeasible to filter the strong terrestrial signals.

Re:LightSquared isn't the victim! (2)

vlm (69642) | more than 2 years ago | (#39044207)

Analogy:
LightSquared tried to buy a plot of cheap residential land to start a chemical/manufacturing plant, which affects nearby residents.
They should have bought a piece of commercial land that supports their requirements.

/. car analogy: They bought property zoned for slot car racing tracks surrounded by residential. Then they said, forget this slot car stuff I'm building a full scale 1000 horsepower indy car / f1 / nascar track and they line up billions of bucks of investment for viewer stands, pork rind fryers, and network broadcast contracts. Then add a dose of blame the victim, those residents complaining about the full size race track being installed in a slot car zoned property should have known better when they moved in decades before the F1 track plan was proposed, after all this is a nation of corruption not a nation of laws, anyone who doesn't know that is a fool who gets what they deserve, just like a woman in a miniskirt in a dark alley (sickeningly distasteful, isn't it?). Finally the indy car / f1 / nascar gets the smackdown from the govt for being complete idiots for trying to install a full scale race track in a slot car strip mall zone and the only people surprised seem to be the track investors who were told it was a guaranteed thing.

In a just world... (-1)

zerofoo (262795) | more than 2 years ago | (#39044065)

LightSquared would get approvals to operate, and the manufacturers of shoddy GPS equipment would be forced by government, lawsuit or both to replace devices that were improperly designed and built.

Yet another case of too big to fail.

-ted

Re:In a just world... (1)

Anonymous Coward | more than 2 years ago | (#39044295)

LightSquared would NOT get approvals to operate because they tried to surreptitiously repurpose satellite spectrum for much, much higher powered ground-based systems, thus causing interference all over adjacent low-powered satellite bands.

Yet another case of too politically-connected to fail without a crapload of useless noise.

-ted

FTFY.

Re:In a just world... (1)

shentino (1139071) | more than 2 years ago | (#39044363)

Amen to that.

For national security reasons though, LS must fail.

At least in its bid to use the spectrum. National security trumps everything else. The question is whether LS should be the one to pay for it.

Fail. Just fail. (4, Insightful)

DeadCatX2 (950953) | more than 2 years ago | (#39044505)

Let's rewind back to the year 2000.

You're a hardware engineer. You've been tasked with building a GPS front end in a cost-effective manner.

You decide to do your homework. You look up the FCC regulations for adjacent frequency bands. Since very high power terrestrial transmissions were prohibited by federal law (i.e. punishable by pound-me-in-the-ass federal prison time for violations), you run the calculations and decide how many -dB/octave your front-end filter needs to exclude signals that you could expect in real world applications.

Sure, you could have gone with a filter that had 2x or 3x steeper roll-off. But why? Your manager asked you to do this in a cost-effective manner, and it's patently illegal for such strong signals to exist.

So you're telling me that a hardware engineer who does his homework and designs a filter that can remove signals which are the maximum legal power is "shoddy"?

Re:In a just world... (0)

Anonymous Coward | more than 2 years ago | (#39045035)

Let's be a little more careful in the terms we're using here. The GPS equipment under consideration includes precision units used by private and government surveyors, some individual units persisting in great condition for twenty or more years with proper maintenance. They cost from about $30,000 to around $50,000 each, and for a private surveyor especially, that's a huge outlay on equipment. Now LS comes along and wants to overrun frequencies next to that of such precision units, which were designed before some of the LS staff were out of diapers, for a band use that was hardly envisioned by anyone when the units came out. This type of GPS unit is used for constructing bridges, high-rise buildings, freeway flyovers, and many other applications that call for high precision. So we are NOT just talking about dashboard nav units, but also aircraft, survey, military, and other uses that involve the safety of thousands of lives; although getting lost with a car GPS or a GPS phone and coming to grief is also a bad thing.

This is a case where time and technology have caught up with the legislation that governs the bandwidth spectrum, not a case of shoddy industry practice.

waitasec... satphone frequencies vs. GPS?? (-1, Flamebait)

Tastecicles (1153671) | more than 2 years ago | (#39044139)

You'dathunk that the GPS system would have been assigned a different frequency (satphones were there first)? Or maybe I'm being dim? OK, there's the issue of bleed, but there's such a thing as DCS/CTCSS squelch (my pocket transceiver has both!!) which ignores anything that's not specifically modulated with the DCS offset and accompanied by a background tone at a specific audio frequency.

As to some GPS receivers having poor PLL tuning: tough. Rather than moan about them being knocked out by (hopefully well designed duplex equipment) packet transceivers, they should force the GPS manufacturers to a: design better receivers that reject bleed signals rather than accept any and all on a 50MHz spread, and b: issue recall and offer replacements at their own cost of all faulty equipment: FCC's own rules state that certified equipment must not cause interference and it must accept any interference. It works both ways, IT DOES NOT PROVIDE AN EXCUSE FOR SHITTY DESIGN.

Re:waitasec... satphone frequencies vs. GPS?? (0)

Anonymous Coward | more than 2 years ago | (#39044339)

Not satphone, terrestrial communications. To sum it up, they wanted to transmit from towers and not surprisingly it overpowered the communications coming from the satellites.

Re:waitasec... satphone frequencies vs. GPS?? (1)

Anonymous Coward | more than 2 years ago | (#39044515)

Ah, you're assuming that GPS and the radio technologies with which you're familiar use the same transmission concepts. They most certainly do not. GPS signals are actually *below* the noise floor, for example, so squelch is utterly irrelevant.

You seem decently versed in communications, so I invite you to read up on how GPS signals actually work. It's fascinating stuff, and you'll have a much better understanding of why LightSquared's proposed system is utterly unworkable.

Re:waitasec... satphone frequencies vs. GPS?? (1)

Tastecicles (1153671) | more than 2 years ago | (#39044563)

I'll have a look... though I'm not sure how a system that operates below the noise floor is expected to work (am I being dim again?).

Re:waitasec... satphone frequencies vs. GPS?? (2)

aXis100 (690904) | more than 2 years ago | (#39044855)

GPS signal are so weak they are below the noise floor. I dont know about you, but that just boggles my mind.

Even with quiet adjacent bands - within the origonal intension of the satellite spectrum allocation - the electronics engineers have a difficult job designing a circuit to process these signals. To then add nearby terrestrial interference that is thousands of times larger is just absurd, the size and expense of the filter required to handle this is impractical to build into most devices.

Yes, you are being dim. (4, Insightful)

sirwired (27582) | more than 2 years ago | (#39044871)

GPS was around way before LightSquared's current plan.

Lightsquared doesn't want to set up a new SatPhone service. They want to use their satellite spectrum for ground-to-ground stations instead. GPS was using their own satellite spectrum LONG before LS decided they wanted to use adjacent spectrum for vastly more powerful (read: interfering) ground service. If all LightSquared wanted to do was set up a SatPhone service, then we would quite correctly be heaping scorn on cheap GPS makers...

It's not "shitty design" when a GPS cannot block out a tidal wave of signal from an adjacent band, when that band was only supposed to contain a garden-hose sized signal. Yes, equipment must "accept any interference", but not if that interference vastly more powerful than the spectrum was originally supposed to deal with.

Lightsquared vs ATT, Verizon, Sprint.... (1)

ruinevil (852677) | more than 2 years ago | (#39044307)

The thing is GPS technology is in tons of random electronics. Since GPS satellites are essentially transmit their identification and an accurate time, GPS is used to keep time in everything from ATMs to our power grid to consumer "atomic" clocks.

Cellphones also use GPS signals to triangulate their position on earth, so that they can connect to the nearest tower with minimal power. This is more FCC doing its real job, protecting everyone from this interference shit.

Re:Lightsquared vs ATT, Verizon, Sprint.... (2)

Megane (129182) | more than 2 years ago | (#39044779)

GPS is used to keep time in everything from ATMs to our power grid to consumer "atomic" clocks.

WTF? WWV [wikipedia.org]

And why the hell would ATMs need a radio signal to keep time?

I am so facepalmed from that completely wrong statement that I'm going to need surgery to remove my hand from my face.

Re:Lightsquared vs ATT, Verizon, Sprint.... (1)

ruinevil (852677) | more than 2 years ago | (#39045439)

No idea why ATMs need GPS, but... some went offline when the US Navy was playing with their jammer off the coast of San Diego, CA, USA. Link [newscientist.com]

Re:Lightsquared vs ATT, Verizon, Sprint.... (1)

ruinevil (852677) | more than 2 years ago | (#39045549)

Also Radio Clocks

Nothing uses your silly 1950s technology, since shortwave receivers are vastly more expensive than GPS receivers due to economy of scale, and also less accurate. Welcome to the 21st century.

So... change the band. (1)

scottbomb (1290580) | more than 2 years ago | (#39044365)

If the currently allocated bandwidth has proven to cause interference to other services, pick a different band of frequencies to use. They'll have to modify their equipment and I'm sure that will be expensive but if they have the capital to do it, I wouldn't rule them dead just yet.

Re:So... change the band. (1)

AbrasiveCat (999190) | more than 2 years ago | (#39044747)

If the currently allocated bandwidth has proven to cause interference to other services, pick a different band of frequencies to use. They'll have to modify their equipment and I'm sure that will be expensive but if they have the capital to do it, I wouldn't rule them dead just yet.

This could work, other than their business model was based on cheap frequency spectrum. The spectrum was cheap for a reason. They might have a problem finding and buying (cheaply) a different piece.

Re:So... change the band. (1)

Megane (129182) | more than 2 years ago | (#39044837)

The problem is that you don't just "pick a band". Frequencies are allocated, in ways that cause them to be effectively "owned" by companies. (Or they're general use, which means amateur radio or low-range purposes.) L2 was trying to to just that, by buying "picking" a cheap ground-to-sat allocation and wanting to use it for ground-to-ground purposes.

The problem is the band, not the equipment (2)

sirwired (27582) | more than 2 years ago | (#39044887)

The equipment design is the easy part; the problem is spectrum scarcity. LightSquared bought up a bunch of cheap satellite spectrum with the idea of using it for a vastly more valuable terrestrial network. While they DO have the capital to change their equipment to use a different band, they DON'T have the capital to actually purchase that band.

Queue the Lightspeed Defenders (4, Insightful)

thrich81 (1357561) | more than 2 years ago | (#39044595)

Does it appear to anyone else that at least half the Lightspeed defenders must be paid shills for the company? Think about it -- GPS has been around for 20+ years and is considered a utility now, the facts of Lightspeed's purchase of the spectrum (only intended for satellite use) are not in question, and neither is the physics of humongously strong signals next to a band where the signals are below the noise floor. And, who gets all excited about some company's spectrum license unless have a vested interest -- it's not usually of much general interest. I'd like to be proved wrong so I can continue to trust he integrity of sites like /. but I'd say , "Reader beware".

Re:Correction Queue the Lightsquared Defenders (1)

thrich81 (1357561) | more than 2 years ago | (#39045109)

Doh, where is the /. edit or delete function? Anyway, yes I meant, "Lightsquared". And I realize that this is sort of an ad hominem attack which is not what I really meant either, but my basic question remains.

4G LTE integrated with satellite coverage (0)

Anonymous Coward | more than 2 years ago | (#39044645)

... could cause interference with the market dominance of At+t and Verizon.

Yippie!! (1)

ch-chuck (9622) | more than 2 years ago | (#39045525)

That's great news - it made my investment in competitor Clearwire (CLWR) jump over 5%.
Not that they don't have their own problems, but at 1.70 at the time, with all the spectrum they own, I could not resist.

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