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Government Wireless Networking

LightSquared Disrupts 75% of GPS Connections In Government Test 197

Freddybear writes with this quote from BusinessWeek: "Philip Falcone's proposed LightSquared Inc. wireless service caused interference to 75 percent of global-positioning system receivers examined in a U.S. government test, according to a draft summary of results. ... The tests worked off an 'extraordinarily conservative' threshold and didn't show the devices' performance was affected, [LightSquared exec Martin Harriman said]. 'If we're affecting the performance of the device — my goodness, we'd like to be sure that doesn't happen,' Harriman said. The laboratory testing was performed for the National Space-Based Positioning, Navigation, and Timing Systems Engineering Forum, an executive branch body that helps advise policy makers on issues around GPS. It found that 69 of 92, or 75 percent, of receivers tested 'experienced harmful interference' at the equivalent of 100 meters (109 yards) from a LightSquared base station."
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LightSquared Disrupts 75% of GPS Connections In Government Test

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  • by SuperKendall ( 25149 ) on Sunday December 11, 2011 @12:35AM (#38332362)

    Solyndria (another company propped up by the white house despite many reports saying the company was not financial viable) was given a ton of money, which the founders (also heavy donors to the Democratic party) got a lot of, then the company went bankrupt but they left with a few million dollar paychecks.

    It doesn't matter if the company folds. Just that Philip Falcone makes money in the process, which he will.

  • by PopeRatzo ( 965947 ) * on Sunday December 11, 2011 @01:10AM (#38332524) Journal

    I'm not saying Republicans are angles or anything like that.

    Then you'll need to get your information somewhere besides

    When a reputable news source reports this, it will mean a lot more.

  • by dbc ( 135354 ) on Sunday December 11, 2011 @01:15AM (#38332562)

    It's very unlikely to be lightspeed signal bleeding over out of their channel. That is reasonably easy to control, and it would show up in 100% of tested receivers. More likely, this is "adjacent channel interference". It is much harder to get a receiver to reject signals in adjacent channels. It takes a difficult/expensive to construct filter. If you go back to the old days of television, you'll note that you don't find adjacent channels allocated in major markets, for instance, because in the early days it was essentially impossible to build a receiver that could reject a strong signal on an adjacent channel. So here we have a case of a receiver looking for a very weak signal, and on an adjacent channel there is a strong local transmitter that you are trying to reject. I'm no surprised that there are issues. Also, because GPS has up till now not had strong nearby, adjacent signals to reject, it could actually be that the first mixer is getting overloaded, so the damage is done before you even get to the first IF filter.

  • by fnj ( 64210 ) on Sunday December 11, 2011 @01:18AM (#38332574)

    Parent is goddam right. Moderators have a problem with the truth? Corruption is corruption.

  • Worse than BPL (Score:5, Insightful)

    by n1ywb ( 555767 ) on Sunday December 11, 2011 @01:19AM (#38332582) Homepage Journal
    This is the worst idea yet. Worse than broadband over power lines, worse than that idea about using gas pipes. I thought the whole point to discontinuing analog TV service and freeing up that bandwidth was to provided wide area Internet. *facepalm*
  • by fnj ( 64210 ) on Sunday December 11, 2011 @01:25AM (#38332614)

    The bureaucracy has a certain very real independence from the government. That can be a problem when the administration is trying to accomplish worthwhile things, but it can also serve as a check on corruption in the government, even if in turn corruption in the bureacracy is a huge problem in itself. Wheels within wheels.

    It's a sad commentary when good things come from parts of the system working at cross purposes, but it works.

  • by fnj ( 64210 ) on Sunday December 11, 2011 @01:37AM (#38332662)

    They are all for sale. Everyone in the System. Corruption is the one thing which is impossible to design out, because by definition corruption *IS* the undermining of the system. Hari Seldon's Foundation is the only way to fight it, and it can't win by fixing the system. The only way is to tear down the old system and build a new one, like the 1992 revolution in the Soviet Union. It's really sad that human nature is the thing that dooms all efforts at effective governing.

  • by BitZtream ( 692029 ) on Sunday December 11, 2011 @01:53AM (#38332774)

    Uhm, blocking GPS functionality is extremely trivial. I assure you, every home in america (and probably most of the first world) has devices that are more than capable of knocking out GPS with only minor trivial changes than ANY RF engineer or EE could do.

    It was never designed to be interference free, thats a silly notion in the first place. It is rather impractical to try and block it however, as it takes massive infrastructure to do it over a large area ... and well, its basically cutting off your nose to spite your face.

    Its more useful to the Chinese to have it working when they invade than it is for them to break it.

  • by The Askylist ( 2488908 ) on Sunday December 11, 2011 @02:12AM (#38332854)
    My reading was that the GPS receivers were picking up the 1552-1559 MHz signal due to being made with cheap parts. That would correlate quite well with the finding that only 3/4 of the receivers were affected - if Light Squared were transmitting out of their assigned band, you'd expect 100% of the receivers to suffer interference.
  • by Anonymous Coward on Sunday December 11, 2011 @02:16AM (#38332868)

    Read more of those issues, or read Inside GNSS: this does indeed impact Galileo and it impacts anything within 600 miles of US borders, which means it impacts intercontinental aviation.

    In a letter filed yesterday (July 19, 2011), Heinz Zourek, director-general for enterprise and industry, wrote to FCC Chairman Julius Genachowski that if LightSquared is allowed to begin broadcasting in the band, “What are now neighbour MSS [mobile satellite service space-to-Earth] transmissions at similar receive powers to RNSS [radionavigation satellite service such as GPS and Galileo] would in future be many orders of magnitude higher and with the potential to severely disrupt reception of RNSS signals.”

    He cited analysis — including ESA studies —carried out in Europe that showed interference effects to Galileo equipment would occur from 100 meters to almost 1,000 kilometers (620 miles), “depending on the type of receiver being used.”

    Emphasis mine. Source: "EC Official Adds Galileo, EGNOS Worries to FCC’s LightSquared-GPS Deliberations,"Inside GNSS, July 20, 2011 []. That's right, July. The Europeans knew this was going to interfere with GPS/Galileo for aviation back in July. They had tested it, and they had numbers showing how far the interference would spread.

    I'll leave it to the tin-foil crowd to speculate on why the FCC is only getting around to publishing its findings now. I'd suggest, though, that what they come up with might not be so paranoid after all in this case. Those who want to dig through some glaring evidence of bipartisan corruption will find it without looking too hard into this story, because the shady deals were conducted practically in the open on this one, from the SkyTerra days on through the past week. The Republicans are already working overtime on trying to assemble a timeline of Falcone's dealings with Obama: if the Democrats were smart, they'd have a team doing the same to show Republican connections, because they are there too (SkyTerra got permission for this back in the Bush era).

    The fact that this story is dying in the back pages while Lindsey Lohan's Playboy spread and the circus clowns that have hijacked the Republican nomination get near-orgasmic coverage is a sad comment on how useless journalism has become.

  • by SuperKendall ( 25149 ) on Sunday December 11, 2011 @02:26AM (#38332896)

    Then you'll need to get your information somewhere besides

    I knew someone would get all huffy about that.

    See, here is the issue. I would love to link to a more "reputable" source than HotAir, because some predjudiced people cannot look beyond a name at facts. But that leads us to a HUGE problem:

    There isn't another source, even though there SHOULD be.

    The facts of the matter are very clear are they not? The interference with the GPS, proven. The donations of Philip Falcone to the Democratic Party, well documented [] and public.

    And yet WHO in the "reputable" media made this very easy and very pertinent connection for us? Is that not in fact the very role it is vital for the media to play, as watchdog for just this kind of ultra-slimy influence peddling? This is the easiest story in the world to find evidence to show to us all, and yet only Hot Air and other "fringe" media bothers to make the simplest of connection.

    The real problem is that the "reputable" media is utterly lost to partisan concerns, death afraid that "their side" may lose something. I truly respect the role the media plays in shining light on the doings of politicians everywhere, and welcome weeding out corruption. But you cannot weed only looking at half the garden.

    So until the point when the "real" media decides to start acting like JOURNALISTS again, I'm afraid you'll have to suffice with information from reputable sources linked together by media you obviously despise - because no-one else is doing that job. I would argue you should probably look at the facts of the matter rather than who is pointing them out; I can discern truth both on HotAir and on HuffingtonPost as required. If you were smart you would seek to do the same rather than get lost in the echo chamber.

  • by Elbereth ( 58257 ) on Sunday December 11, 2011 @03:15AM (#38333008) Journal

    The strange thing is that he's got a userid number around mine, which says that he's been here at least ten years. How can you go use a website for over ten years, without picking up that the moderation system is capricious, random, and certainly grounded in groupthink -- but corrupt? "Corrupt" is one of the few negative terms I wouldn't use to describe Slashdot's moderation system. One of the few actual advantages that it does have is that it's not corrupt. Even if Apple or Microsoft started paying people to mod up comments that praised them, there'd be outraged people downmodding those comments just as quickly.

    I think people attach too much significance to karma and moderation, anyways. It's pathetically easy to game the system (just pander to whatever the prevailing groupthink is on a subject... or brazenly challenge the prevailing groupthink and say, "I'll probably get modded down for this, but..."). When I first started on Slashdot, I was an unrepentant karma whore, just to see how high I could get my karma. Then they hid the number, which killed that game. I've never had a (Score 5: Troll) comment, though, and I've always wanted one of those. Maybe some day... a boy can dream.

  • by Megane ( 129182 ) on Sunday December 11, 2011 @03:16AM (#38333010) Homepage

    It's not that they're using "cheap parts". It's that the signal from those little solar-powered tin cans whizzing around in the sky is so weak that adding a notch filter to increase selectivity would significantly affect the ability to receive the signal at all. And they want to drop this elephant right next to it.

    But hey, they paid their donations to the Party, right?

  • by Anonymous Coward on Sunday December 11, 2011 @07:05AM (#38333684)

    You are ignorant of the history of the L1 band that GPS and a number of other satellite services occupy. GPS equipment (and their front-end filters in particular) has been designed under the assumption that the surrounding spectrum would only be occupied by satellite communications which have output power many orders of magnitude less than what LightSquared is proposing. It is not the fault of GPS manufacturers that spectrum that has traditionally been used for satellite communications (and it should be considering the propagation properties through the atmosphere at these wavelengths) was sold in an underhanded way and without proper oversight to the effects on surrounding users.

  • by PopeRatzo ( 965947 ) * on Sunday December 11, 2011 @09:17AM (#38334192) Journal

    TFA is from Business Week.

    I understand that, but the Business Week article doesn't say anything like the text SuperKendall used in his link to the HotAir article.

    This is done all the time. Someone wants to make a political point. They link to some blog's hit piece article which links to a reputable article which does not make the same conclusion and then viola! a = c.

  • by Anonymous Coward on Sunday December 11, 2011 @02:24PM (#38336524)

    But THIS news is about HOW they actually got the FCC to switch the space based spectrum adjacent to GPS to be used for a terrestrial based spectrum. The FCC rules were setup to not have a large power ground based spectrum next to a weak space based spectrum. Somehow Lightsquared 'convinced' them to change the rules. So this would be like a race track owner bribing city hall to rezone the houses on the other side of your street to let him put in a drag strip. If you have a problem with the noise of the open header cars screaming down the track it's your fault because all you need to do is soundproof your house to not let in the sound of racing cars into your house.
    Remember that the Lightsquared signals will still be hitting the GPS receivers, it becomes the GPS receiver's problem to somehow filter them out. A tough thing to do when loud noise is next to quiet GPS signals from satellites. And nearly impossible to retro fit the millions of GPS receivers already in use.

  • by AF_Cheddar_Head ( 1186601 ) on Sunday December 11, 2011 @09:27PM (#38339190)

    And please explain to me how the millions that were given to Solyndra come close to comparing to the billions that Bush and his Republican mates gave to the contractors to carry out the wars in Iraq and Afghanistan. At least Solyndra did not result in thousands of dead Iraqi and Afghani along with burning through the good will we might have had from the rest of the world after 9-11.

    Remember that the Democrats and Republicans actually cooperated on a few things in the 90s, created a pretty good economy and had us showing a surplus paying down the debt, then Bush came in and all the changed. Bush even insisted that the entire Iraq war was and emergency that shouldn't show up in the normal budget, kind of disingenuous don't you think.

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