Slashdot Mirror


LightSquared Disrupts 75% of GPS Connections In Government Test

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."

39 of 197 comments (clear)

  1. This is being whitewashed from the white house by SuperKendall · · Score: 5, Interesting

    This story is bad enough until you find out the white house was pressuring people to hide issues related to LightSquared.

    And Philip Falcone is a huge donor for the Democratic Party.

    I'm not saying Republicans are angles or anything like that. I am saying this a very bad case of corporate ties directly to the whitehouse that is threatening to disrupt a major technology just to make some money...

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
    1. Re:This is being whitewashed from the white house by ceoyoyo · · Score: 4, Interesting

      If it interfered with GPS, they'd get caught awfully fast and LOSE a lot of money. Interfering with GPS doesn't just mean that someone's turn by turn directions get messed up. A lot of things now depend on GPS, mostly for the time information.

    2. Re:This is being whitewashed from the white house by LtGordon · · Score: 5, Funny

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

      You could, however, say they are quite obtuse.

    3. Re:This is being whitewashed from the white house by Shadowruni · · Score: 5, Funny

      But the Republicans are Right (angles)! Thank you ladies and gentlemen I'll be here all week. Try the fish!

      --
      "Chinese Amazons, power armor, laser swords.... things just meant to be." - Shampoo, A Very Scary Bet
    4. Re:This is being whitewashed from the white house by Anonymous Coward · · Score: 5, Interesting
    5. Re:This is being whitewashed from the white house by fnj · · Score: 4, Insightful

      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.

    6. Re:This is being whitewashed from the white house by TubeSteak · · Score: 4, Informative

      Then you'll need to get your information somewhere besides hotair.com.

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

      TFA is from Business Week. The HotAir.com article only quotes from Business Week and includes other relevant facts that seem well sourced.
      I'm not sure how the GP ended up talking about Republicans, but this was reported by a reputable news source.

      --
      [Fuck Beta]
      o0t!
    7. Re:This is being whitewashed from the white house by Anonymous Coward · · Score: 4, Interesting

      On the upside, the Military has just found an new way to jam the GPS of enemies on the battlefield.

      On a more serious note, WTF, that has to be some serious bleed over. Almost all of the frequencies used by GPS are reserved government frequencies. Light Squared will use 1525-1559 MHz according to what I have found. The nearest GPS freq is 1575.42 MHz but is the L1 freq explaining why so many receivers get jammed completely. Light Squared has a serious engineering problem, because they either produce nasty sub-carriers outside there assigned frequencies, or they just ignore their assigned frequency and use more bandwidth that they have be allocated.

      This link is to the a great Freq. Allocation Chart for the US. While it says 2003, it still applies to this case.
      http://www.ntia.doc.gov/files/ntia/publications/2003-allochrt.pdf

    8. Re:This is being whitewashed from the white house by The+Askylist · · Score: 4, Insightful

      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.

    9. Re:This is being whitewashed from the white house by Anonymous Coward · · Score: 5, Informative

      I'm an electrical engineer. I did my doctorate in a GPS lab working on safety-of-life applications (landing planes and such). The LS issue has been a very hot topic of discussion in the technical community for most of the past year. At the annual ION GNSS conference this past September, there was a panel discussion on the preliminary test results described in TFA. Out of approximately 600 people in the room, there were exactly two who expressed opinions supporting LS's contention that the interference to GPS would be insignificant: one guy was the LS General Counsel, and the other was a guy who is claiming he has retrofit kits (RF notch filters) that will eliminate the interference. It should be noted that, when asked how his kits would be fitted to the millions of GPS receivers already in the field, the latter person had absolutely no answer.

      It is not at all a stretch to say that very nearly 100% of the people who have done LS testing, or evaluated the results from an engineering perspective, conclude that the effects as proposed will be somewhere between "significant" and "catastrophic."

      --Jake

    10. Re:This is being whitewashed from the white house by sessamoid · · Score: 4, Funny

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

      You could, however, say they are quite obtuse.

      Following that logic, Republicans must, therefore, be wrong. Because you cannot be both obtuse and right.

      --
      "No, no, no. Don't tug on that. You never know what it might be attached to."
    11. Re:This is being whitewashed from the white house by D'Sphitz · · Score: 4, Informative

      And Philip Falcone is a huge donor for the Democratic Party.

      According to Wikipedia

      The Federal Election Commission has no record of Phil Falcone, a registered Republican, nor LightSquared Chairman and CEO Sanjiv Ahuja of having ever contributed to President Obama’s political campaigns.

      Among the issues being raised is if political contributors received favorable treatment by the Obama administration. Since 2007, a key investor in LightSquared, Phil Falcone, has donated $85,500 to Republicans and $50,500 to Democrats.

      Not what I'd call a "huge donor for the Democratic Party".

    12. Re:This is being whitewashed from the white house by Megane · · Score: 5, Insightful

      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?

      --
      #naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
    13. Re:This is being whitewashed from the white house by dmomo · · Score: 4, Funny

      Ok. This thread is starting to go off on a tangent.

    14. Re:This is being whitewashed from the white house by dmomo · · Score: 4, Funny

      No that was his cosine.

    15. Re:This is being whitewashed from the white house by vlm · · Score: 5, Informative

      The nearest GPS freq is 1575.42 MHz but is the L1 freq

      Very close but not quite. The L1C signal is not a simple continuous carrier like the old transit sats from the 50s/60s. The data rate is somewhere around ten megabits and it modulation is BPSK. The exact answer requires more detail but the actual transmitted BW will end up maybe 10 megs higher and 10 megs lower than the center theoretical carrier. Which is getting uncomfortably close to the lightsquared signal.

      So... that's 1565 or so, vs the interference at 1559. So you head over to minicircuits.com (a seller of many microwave components, including the high pass filter you are trying to purchase) and look for a coaxial filter with a curve showing almost 0 dB attenuation at 1565 and up to keep your noise figure usable, and at least 60 dB out of band attenuation at 1559. Then you realize why the EE types claim "its a law of physics" that this simply cannot be worked around. Oh and note the ones that don't even come close to making the grade are roughly the size weight and cost of a very small cell phone. Generically building a filter in that frequency range with those specs is impossible, but building the device to that exact frequency spec and stable over any temperature range makes it even more impossible.

      Before the sorta knowledgeable DSP types jump in, yes, you can get filter curves like that using DSP. However you need a analog input clean enough to do the DSP on it... So, again, you're screwed. Just plug your 60 dBm 3rd order IMD preamp into your 32 bit A/D 10 GHz A/D converter and then process it. This is technobable of the finest level, components with specs like that Might exist in just 50 years or so, but they sure don't now.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    16. Re:This is being whitewashed from the white house by vlm · · Score: 4, Interesting

      I'm an electrical engineer

      Good

      other was a guy who is claiming he has retrofit kits (RF notch filters) that will eliminate the interference. It should be noted that, when asked how his kits would be fitted to the millions of GPS receivers already in the field, the latter person had absolutely no answer.

      Run the numbers on the Q factor required and the maximum possible passband attenuation to keep the noise figure of the front end usable... If you know what "snake oil" is WRT crypto it sounds like this guy's offering sounds suspiciously like "frequency grease" WRT RF.

      Note that if the problem is front end overload, his snakeoil/freqgrease might be a simple 10 dB attenuator, probably being sold at an immense markup. If would be easier to duct tape aluminum foil to the existing antenna until the incoming signals are knocked down enough that the FE is not overloading but optimistically there is still enough RF signal left to decode.

      This is assuming its not at the RF technology level of those stickers you put on cell phones to magically do things that sound good.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    17. Re:This is being whitewashed from the white house by Anonymous Coward · · Score: 5, Informative

      Run the numbers on the Q factor required and the maximum possible passband attenuation to keep the noise figure of the front end usable... If you know what "snake oil" is WRT crypto it sounds like this guy's offering sounds suspiciously like "frequency grease" WRT RF.

      Note that if the problem is front end overload, his snakeoil/freqgrease might be a simple 10 dB attenuator, probably being sold at an immense markup. If would be easier to duct tape aluminum foil to the existing antenna until the incoming signals are knocked down enough that the FE is not overloading but optimistically there is still enough RF signal left to decode.

      This is assuming its not at the RF technology level of those stickers you put on cell phones to magically do things that sound good.

      I am intimately familiar with the RF arguments. The proposed notch filter is indeed snake oil, but not for reasons of insufficiently steep stopband rolloff. Rather, it's a relatively bulky thing which will work just fine for the receivers produced by the guy's company (Javad), and maybe even other receivers that could be retrofitted. But it is totally unusable for most embedded receivers (handhelds, etc.) due to size (and cost), and there are a lot more of those deployed in the world. The "snake oil" part of the argument is that he is being spectacularly disingenuous about it: when asked how he intends to retrofit every TomTom, Garmin, GPS-enabled wristwatch, and mobile phone already out there in the field, he just waves his hands and says, "those devices won't be affected."

      While I'm on the subject, people seem to be unaware of a further bit of deception on LS's part. Their initial proposal included two bands just below GPS (the so-called "Low 10" and "High 10"). When testing showed that the resulting interference would make the proposal a non-starter, LS submitted a modified proposal in which they would only the lower of the two bands (farther away from GPS), and at a lower broadcast power level. The thing is, LS never stated that this was their intended final configuration. Indeed, upon further discussion, it emerged that this revised proposal was intended only to placate objections in the short term, and that LS fully intends to use both bands and the higher power levels (as in their original proposal) eventually. In other words, the potential interference problem was never addressed, just kicked down the road a bit.

      In short, the proposed filter was far more sophisticated than the bits of aluminum foil you might see for sale on QVC on channel 179 at three in the morning... but it's virtually meaningless in any practical sense.

    18. Re:This is being whitewashed from the white house by Thing+1 · · Score: 4, Interesting

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

      I don't know; I see it as similar to a RAID array: every drive I purchase will fail, but by arranging my activities correctly, I will never lose data. Similarly, corruption may be present in all areas of government, but by arranging it just right it has made it more than 200 years. Current trends seem to indicate it won't make it to 300.

      --
      I feel fantastic, and I'm still alive.
    19. Re:This is being whitewashed from the white house by HereIAmJH · · Score: 4, Informative

      So if LightSquared goes live, 75% of consumer (and possibly commercial) GPS units will have serious problems.

      If you had been following along, you would know that consumer GPS units are not affected. That has already been resolved when LightSquared agreed to hold off using the upper band for a period of time, allowing most consumer GPS units to be replaced by normal obsolescence. Their use of the lower band will only affect precision GPS units.

      If I was in to conspiracy theories, I'd say that little fact is left out of news articles intentionally to rile up the general population against LightSquared.

      Looking at it as someone who has been following this for months, and has no stake in the game either way, it looks more like this; precision GPS manufacturers didn't feel the need to filter a band in between two that they were using since it wasn't really being by anything with any power, and it could have cost them a few more pennies per unit. And then LightSquared managed to somehow get the FCC to consider opening the band to terrestrial transmitters. Now it's a multi-billion dollar pissing match. Nobody is completely right, and nobody is completely wrong.

      --
      Another day, another update to a Google android app.
  2. You don't understand how this works do you. by SuperKendall · · Score: 5, Insightful

    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.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
    1. Re:You don't understand how this works do you. by Elbereth · · Score: 4, Insightful

      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.

    2. Re:You don't understand how this works do you. by lightknight · · Score: 4, Interesting

      Now, now, the party of purple is equally corrupt in both its left and right branches. They only differ on what kind of corruption they specialize in.

      But don't worry, come 2012, you'll get to pick which candidate from the party of purple you prefer, then spend the next 4 years crying yourself to sleep at night, because you know that no matter who is elected, it will be more of the same. And it will be same for your children, and your grand-children, and your great grand-children, who will work for less money that you earn on a Friday afternoon right now, and have less throughout their lives.

      Remember to eat your bread and visit the circus on your way home. It's good bread, if a little stale, and the circus has giraffes. Repeat after me: "I live in the greatest country in the world! I worship authority! If I am struck, I will not strike back! The wiretaps are there for my freedoms, which everyone else on the planet is jealous of, and wants to take from me! USA! USA! USA! USA!"

      --
      I am John Hurt.
  3. Farm GPS, airplanes, and who owns the bandwidth by Anonymous Coward · · Score: 4, Informative

    One of the big issues is that those giant combines and harvesters on farms use GPS, so the farming industry is upset http://westernfarmpress.com/government/lightsquared-threat-gps-even-filters Lightspeed owns the bandwidth adjacent to GPS, but the GPS devices are still affected by transmission on lightspeed's bandwidth. So it isn't really "lightspeed zmog destroy teh GPS" by doing some dastardly deeds, it is them trying to use the bandwidth they purchased and older GPS devices not able to handle the interference (even tho they are class B and must not create interference and must accept interference). Airplanes are another issue with interference. http://macsblog.com/2011/02/should-i-worry-about-gps-jamming/ really, though, just a clash of the lobbyists in washington on who has to pay extra to make lightspeed able to use their bandwidth

    1. Re:Farm GPS, airplanes, and who owns the bandwidth by jchernia · · Score: 5, Informative

      Yes, but the towers are broadcasting signals that are orders of magnitude more powerful to ground receivers than the gps satellites. If Lightspeed was a satellite phone system (so if it was another satellite system producing the crosstalk), it would not interfere even if the frequencies were directly adjacent.

    2. Re:Farm GPS, airplanes, and who owns the bandwidth by Anonymous Coward · · Score: 5, Interesting

      I'm not an expert, but read some back issues of GPS World. Lightsquared is doing dastardly deeds - this frequency was never intended for terrestrial broadcasting. They pulled a fast one and got this for a steal. The FCC screwed up big time - either incompetence or someone was asked to do a favor or paid off. There's a lot of FUD - Lightsquared has been planting stories claiming that the GPS devices won't work do to shoddy engineering. The facts are that they should be building terrestrial base stations that broadcast near GPS frequencies and not have to at least go through a thorough review and pay what this spectrum is really worth.

      You don't see consumer electronics or their suppliers companies publicly complaining because it's not in their best interest to show a weakness at this time. e.g. if company A says that this will impact them, then company B can use that statement when they pay a visit or market to A's customers.

      Fortunately this only impacts the good old USA. The rest of the world can continue to reap the benefits of GPS while they ramp up their systems. (Glonass has been on the rise. Galileo is finally making progress. Compass is on its way and hopefully they will eventually publish their ICD.)

    3. Re:Farm GPS, airplanes, and who owns the bandwidth by dbc · · Score: 4, Insightful

      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.

    4. Re:Farm GPS, airplanes, and who owns the bandwidth by DeadCatX2 · · Score: 5, Informative

      It's not so much that the nearby frequencies need to be silent. I believe it was actually the case that those frequencies were originally licensed for low-power signals. So when the hardware engineer was designing his GPS receiver circuit, he would use the expected max power that could be licensed for that band in his calculation for determining how many -dB/Octave his filter needs. Now LS comes in and wants to relicense that spectrum for signals of many orders of magnitude more power; the circuits were simply not designed to handle this because such signals were illegal at the time of manufacture.

      It's not the hardware engineer's fault that the adjacent bands were "zoned" to be residential and now LS wants to come in and build an airport.

      --
      :(){ :|:& };:
    5. Re:Farm GPS, airplanes, and who owns the bandwidth by sillivalley · · Score: 5, Informative

      Nope, it's not adjacent channel interference -- the precision positioning people use a correction signal (from a satellite) in L band, below the GPS L1 signal, that is completely swamped by the LightSquared system -- these precision positioning systems, which are also used in highway construction and other large developments as well as in large scale agriculture, are among the systems that the study identified as impossible to make work even with a redesign -- these bands were meant for weak signal reception of satellite signals, NOT for multi-kilowatt ground stations.

      And when you talk about adjacent channel, remember that GPS boxes aren't so much receivers as correlators -- and they are working with signals that are effectively below the noise floor -- that's why correlation techniques have to be used. What might be acceptable as adjacent channel in other modes is devastating to correlator-based designs.

      See for example the FAA report at:

      http://scpnt.stanford.edu/pnt/PNT11/2011_presentation_files/09_Bunce-PNT2011.pdf

    6. Re:Farm GPS, airplanes, and who owns the bandwidth by Anonymous Coward · · Score: 5, Insightful

      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.

    7. Re:Farm GPS, airplanes, and who owns the bandwidth by sillivalley · · Score: 4, Informative

      Sorry, also look at the Parkinson presentation from the same Stanford Precision Time and Position Conference --

      http://scpnt.stanford.edu/pnt/PNT11/2011_presentation_files/01_Parkinson-PNT2011.pdf

      He gives a very nice spectrum on slide 4 -- note the little bump at the bottom labeled "Starfire/Omnistar" -- that's the correction signal used by the John Deere precision GPS system, and others, broadcast by Inmarsat III. It's f*ing buried under the proposed LightSquared 10H signal at 1550.2, and still under the skirts of their 10L signal at 1531!

      You can't design around that!

      ANYTHING carried by Inmarsat III in that band just below GPS L1 is so screwed if LightSquared uses those frequencies!

      this is also a pretty clear indication that FCC was bought off at a high level, and their technical types didn't get to look at it -- they would have screamed.

  4. More Context by Anonymous Coward · · Score: 5, Informative

    This came out during the week, but was overshadowed by the news that Falcone And Friends got Wells Letters, SEC notices that are basically game-over. Investors in Harbinger Capital Partners, Falcone's hedge fund, are likely to flee, but they'll be limited in their ability to withdraw funds. This has happened before to Harbinger in 2009, and Goldman Sachs seems to have gotten preferential treatment in exiting.

    The LightSquared bit is juicier, though, because of the hints of corruption that have squeaked out through the press. Air Force General William Shelton, testifying before Congress about LightSquared and the interference that its plans could cause GPS, complained that the White House had told him to change his testimony to make it seem that he was less opposed to LightSquared's plans. There are also allegations of $30,400 donations being given to the Democratic Party by Falcone and LightSquared's CEO on the days of meetings and on days when meetings were arranged.

  5. Worse than BPL by n1ywb · · Score: 4, Insightful

    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*

    --
    -73, de n1ywb
    www.n1ywb.com
  6. Re:Not a surprise by ColdWetDog · · Score: 4, Informative

    Let's get over the sensationalism and realize the real problem: We had false expectations of GPS and therefore should not have depended on this technology in defense systems.

    You do realize that the US military owns the GPS system. It seems to have worked out pretty well for them. Of course, no tech is perfect but I don't understand what you're whining about. It's not like Lightspeed is going to put transmitters in Afghanistan and if some nefarious persons try to block GPS signals with a transmitter well, the military has some nice little tools to solve that problem.

    --
    Faster! Faster! Faster would be better!
  7. Stanford Symposium held 2011/11/17 by sillivalley · · Score: 5, Informative

    Look at the docs posted for the recent symposium at Stanford:

    http://scpnt.stanford.edu/pnt/

    Opening comments on how LightSquared destroys GPS:

    http://scpnt.stanford.edu/pnt/PNT11/2011_presentation_files/01_Parkinson-PNT2011.pdf

    the FAA report on testing:

    http://scpnt.stanford.edu/pnt/PNT11/2011_presentation_files/09_Bunce-PNT2011.pdf

    The LightSquared idea is a good one, but not on the frequencies they've selected!

  8. The problem is, who else makes this link? by SuperKendall · · Score: 4, Insightful

    Then you'll need to get your information somewhere besides hotair.com.

    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.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
  9. No interference by stooo · · Score: 4, Interesting

    They might be allocated the bandwidth, but this means they are responsible for interference. Of course they probably respect the FCC requirements, but they still need to consider interference, aqnd this one is an obvious case. Transmitting 42 dBm or so a few MHz away from a band such as GPS, and that on the scale of a nation IS a bad case of interference.

    I expect the project to fail anyway because the handset manufacturers have no way to implement that band in a suitable phone with GPS.
    This means expensive hardware in each compatible phone. Did you look at the RF HW of a typical phone ? it's a spagetti of PAs and filters. This band would mean passing from 2 RF paths to 3, 50% price increase. Furthermore, putting another antenna is hopeless, and the phone will jam it's own GPS, if available. Nobody in the industry wants such a monster, except Lightsquared.

    For civilian GPS receiver, who are more sensitive due to a design nore vulnerable to interference (first LNA before the first filter), they will be affected. GPS performance will be unacceptable in some places close to antennas, and probably compatible handsets operating in the vincinity will affect them also.

    --
    aaaaaaa
  10. Re:Not a surprise by gnu-sucks · · Score: 4, Interesting

    Here's the problem: You can block "Lightspeed" from deploying devices known to cause harmful interference to GPS signals. Big deal. What you can't do is make it "illegal" to jam GPS. Well, you can make it illegal, but it's a matter of enforcement. Expecting it to work 100%, especially in a battle field, is stupid. Your enemy will build GPS jammers by the dozen and hide them all over the place once they realize this is how you guide your missiles.

    All I'm saying, is that this is a symptom of a larger problem: depending on easily jammed GPS.

    I realize the military will just triangulate and find the jammers. But a jammer just has to hide their equipment in nearby hospitals and grocery stores, and use intelligent timing and antenna arrangements.... they can make triangulation a very difficult and time-consuming operation. And once the devices are found and destroyed, it's another $15 to deploy another one somewhere else.

    I think it's a good idea to try and prevent what you can, such as by not certifying equipment that causes harmful interference. But let's not think this is the real problem with GPS...

  11. Re:How is this not an impeachable offense? by Anonymous Coward · · Score: 4, Informative

    Your comment is typical of paid pro-GOP astro-turfng on Slashdot.

    Falcone is a registered REPUBLICAN and there is no record of any donations to the Obama campaign. Apparently he did make some donations in some congressional races, but the bulk of his donations were to REPUBLICANS.