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."
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
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
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
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.
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
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!
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.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
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!
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
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
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...
Here is something visual. http://i.imgur.com/HgpdX.jpg
U.S. Frequency Allocation Chart
PDF -- 2003 U.S. Frequency Allocation Chart http://www.ntia.doc.gov/files/ntia/publications/2003-allochrt.pdf
If you fly on airplanes, or live near an airport, you should care:
Lawrence Person (lawrencepersonh@gmailh.com (remove all "h"s to mail)
http://www.lawrenceperson.com/
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.
No, that's not the way it works. "intelligent timing and antenna arrangements" greatly impede the ability to jam, and triangulation is not necessary to destroy it unless you are shooting at it with artillery. As for someone turning a hospital into a location from which a military offensive is launched from, the person turning on the jammer is in the wrong, not the people retaliating against attack.
Learn to love Alaska
You are probably referring to Javad Ashjaee. The guy is a GPS authority, with a long track in contributions to the community. He founded a few companies, the latest one Javad, which creates high quality precision receivers. He is someone who until two months ago, I would have never doubted. But then he started contradicting himself with his message. First, he started to complain how lightsquare does affect his receivers. Then he proposed ending the P-code as a way to mitigate for this (http://www.gpsworld.com/gnss-system/news/to-solve-lightsquared-issue-javad-ashjaee-calls-end-p-code-encryption-11887). The P-code is the encrypted signal that only military has access to. And now, he claims that there are no problems. While I kind of follow his reasoning, he needs to be more coherent in his message.
I mean, he first claims that something is wrong and proposes one crazy solution (ending P-code), and then another solution. So it is kind of like saying "they are messing up the signal, but this is great because now I can sell filters and maybe get some money from Lightsquare for supporting them".
The guys is still a smart dude and I wish him all best with his business. But my employer bought a receiver from his company for 15k and don't feel like spending a single cent more for fixing something that someone else broke. Lightsqaure is a good thing however. For precision receivers, this allows better availability of correction data for RTK measurements in cm-precise positioning.
So here is my opinion here: what Javad is saying *does* make sense in general. Please ignore his bad way of expressing this in the media, his apparent contradictions, his strong wordings that sound often arrogant, and let's try to understand his points, which are not that crazy after all.
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.
Defense systems have had direct P(Y)/L3 acquisition for a while. On a battlefield, they can also eliminate the interference with a HARM if they so choose. And they have inertial guidance and other backup systems for when GPS is being jammed. This isn't about defense; this is about civilian GPS use.
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.
1575.42MHz is first of all just the carrier frequency. All useful signals have a non-zero band width. Second, GPS receivers are required by design to not filter out adjacent spectrum because the actual received frequency will differ due to Doppler shift.
GPS signals are extraordinarily weak. The cell towers are over 1000 times as powerful as the actual satellites, and the satellites are so much further away, that the LightSpped signal at a GPS device is often a billion times stronger than the GPS signal. Considering how close the frequencies are that means that an incredibly strong filter is needed, and it must be designed to have near zero attenuation of actual GPS signals, since they are so weak already.
GPS receivers have historically been designed assuming that the nearby signals like those in LightSpeed's frequencies would not be substantially stronger than a GPS signal, since that frequency range was reserved for satellite communications. Even if they had been designed with LightSpeed in mind, it is virtually impossible to design a filter that would work and not harm the performance of GPS without substantially increasing the size of the receiver.
I'm honestly shocked that up to 25% of the receivers did not experience any interference. These were probably large receivers that already had excellent filtering, but which would be completely unsuitable for use in say a cell phone.
Stylish sheet to fix many problems in Slashdot's D3: https://gist.github.com/801524
Simply put, LightSquared should have known that use of high power terrestial base stations could adversely affect GPS receivers and they should have made an effort to see if a work-around was possible before acquiring rights to the frequency bands. Since they didn't, LightSquared management have probably opened themselves up to shareholder lawsuits.
The original allocation for the LightSquared frequencies was for satellite based transmitters and it is up to LightSquared to prove that shifting to terrestial transmitters will not cause harmful interference.
A Shadeless room is a brighter room.