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Military Tech: GPS and Networking

king of birds writes "The New York Times has an interesting article on the present military use of GPS. While some units have rather modern system that can graphically display locations of other troops, others rely on 10-year-old 5 channel receivers. Kind of odd when I can 12 channels on my civilian model (with admittedly lower spatial accuracy)." aaronvegh writes "From the Canadian Press, a story about how a US infantry division uses a system of transponders and servers to track friendly and enemy units, from the headquarters to inside individual tanks. Talk about total information awareness! No friendlies were harmed in the making of this story."

35 of 185 comments (clear)

  1. GPS doesn't stop you getting lost. by Boss,+Pointy+Haired · · Score: 4, Funny

    It just tells you exactly where you are lost.

    1. Re:GPS doesn't stop you getting lost. by unicron · · Score: 2, Insightful

      Well that's why you set up a way point of your home base/camp site/vehicle. When you get lost, you tell it to return to here, and you get a pretty little arrow that says "home is 3 miles that way" and the arrow constantly is updated on the fly. It doesn't just list friggin longitude and latitude numbers..well, maybe yours does.

      --
      Finally, math books without any of that base 6 crap in them.
    2. Re:GPS doesn't stop you getting lost. by AndroidCat · · Score: 3, Insightful
      That doesn't help in rough country where the straight line path isn't the best.

      As the farmer said when asked for directions: "If I was you and trying to get there, I wouldn't start from here."

      --
      One line blog. I hear that they're called Twitters now.
  2. Obligatory plug... by Rorschach1 · · Score: 3, Interesting
    Many /.'ers are probably already familliar with APRS for position reporting over ham radio. APRS has some serious limitations, though, and there's an effort to develop a new, extensible, open protocol at opentrac.org. Things are just starting to take off, with prototype hardware in use and a couple of test programs written. Check it out and see what you can contribute.

    My personal goal: A poor man's Land Warrior system for paintball scenario games. =]

    1. Re:Obligatory plug... by Rorschach1 · · Score: 2, Insightful

      Day-to-day operations give you the chance to test the system out under a real load, so you know it'll work in an emergency.

      The biggest problem I've seen is that the channel is just overloaded in many places. People using excessively long paths, too many high digipeaters too close together, and too-frequent transmissions.

      OpenTrac doesn't fix that (there are methods already being discussed and tested for those problems), but it does let you do all sorts of nifty stuff with telemetry and such. And it's far easier to encode and decode than APRS, so it's better suited for small microcontrollers.

    2. Re:Obligatory plug... by Rorschach1 · · Score: 2, Informative
      The current hardware's the same as APRS. You could reprogram a TinyTrack3 and it'd do OpenTrac as easily as APRS.


      A big focus of the project is open hardware and software - something that's sorely lacking in APRS. Take the MIM, for example. It's a pretty clever little telemetry transmitter, but it sells for $79. Seems pretty excessive for a circuit board with a PIC and some support circuitry. No source code is provided, either. I'm working on something similar, but it'll be completely open source, provided under the BSD license. Source, CAD drawings, foil patterns, and all that stuff will be published for anyone to duplicate or modify.

    3. Re:Obligatory plug... by pe1chl · · Score: 2, Insightful

      Are you sure that any of the APRS problems are related to the message format?
      If not, it is very unwise to create a new, incompatible, message format "just because this one is nicer".
      The average ham radio operator considers something like a PIC or a TNC an "investment for life" and will not be prepared to build or construct something new to do essentially the same as what he already has, even if it does it in a better or cleaner way!
      This probably is because many hams are just trying out different things, and that of course is the main purpose of the hobby. So, many people will go on APRS just to see what it brings them, not to follow the state of the art or to keep improving things "because it can be done better".

      I think that you will find that even when Opentrac is 20 times better than APRS (which I have not yet seen from any of the documents on the site), in 10 years time still most people use APRS. It was there first, it has been implemented on many platforms, and it is in use by a large group of people that have no urge to change. It is like IP version 4. Sure, IP version 6 is nicer but nobody is going to use it as version 4 does the job fine.

      Of course you are right about little open hardware and software being available for APRS. But as long as there are no legal problems with that (are there?) it would seem to be better to just work on solving THAT problem (i.e. design and publish an open source APRS device), rather than re-invent the wheel and find yourself largely ignored by the userbase.

      Rob

  3. Risky by sakusha · · Score: 3, Insightful

    Isn't it a little risky to put location transponders on all your military units? If the enemy cracks your transponder codes, they can easily target you.

    1. Re:Risky by f97tosc · · Score: 4, Insightful

      Isn't it a little risky to put location transponders on all your military units? If the enemy cracks your transponder codes, they can easily target you.

      Similar concerns can be raised about almost any military technology or activity. Don't use radio - the enemy might hear what you say! Don't use radar - the enemy will know where you are! Don't open fire - you will reveal your position!

      Military winners are willing to take such risks in pursuing their objectives. They know that being aware of the situation and acting proactivly and agressively is more important than never revealing anything to the enemy. There are of course circumstances where one should be stealthy, but wars are not won by armies remaining completely hidden in cover.

      Tor

    2. Re:Risky by NanoGator · · Score: 3, Funny

      "Isn't it a little risky to put location transponders on all your military units? If the enemy cracks your transponder codes, they can easily target you. "

      Suddenly a fleet of vehicles simultaneously comes to a complete stop. "An update to your GPS software is available. Would you like to download it now?"

      --
      "Derp de derp."
    3. Re:Risky by Dolphinzilla · · Score: 2, Informative

      Most of these things are designed with LPI (low probability of intercept) in mind - they are nearly impossible to detect with even the best equipment - now consider the technology that our opponents have and it comes out to be 0 risk. The benefit of knowing where your forces are, to prevent fratricide, far outweigh the astronomical odds of having your transponder tracked.

  4. Technological goodness! by Anonymous Coward · · Score: 2, Funny

    I want to adapt this system to graphically display locations of all my girlfriends.

    1. Re:Technological goodness! by BrainInAJar · · Score: 3, Funny

      Solution:
      2 recievers, broadcasting their location to a central server.
      Put one in each hand.

  5. Failure rate by Anonymous Coward · · Score: 4, Insightful

    Kind of odd when I can 12 channels on my civilian model

    Of course, your civilian model probably fails 1% of the time, and wouldn't survive a day in a sandstorm, in part due to it's fragile electronics.

    The Military version, while only 5 channels, is probably much more robust then your puny little civilian model.

    1. Re:Failure rate by DonaldBeckman817 · · Score: 2, Informative

      we have a 'civ' model of Germen Summit GPS. It has survived over a year of constant abuse in our tool box, and has been dropped off 3 different towers that were over 100' tall. Then we dropped it off our main tower, 500'. The batteries popped out and went somewhere but it still works! Made a big THUD and slight crater in the ground....


      I love working with a wISP, its sooo much cooler than boring old regular ISP work...!

    2. Re:Failure rate by bugnuts · · Score: 3, Informative

      I have used both military and civ models.

      Civilian models are designed to be lightweight, waterproof, and reasonably accurate. Some will average selective availability to get a statistically more accurate reading. A 12-channel chip is the size of a dime. The newer ones with integrated map data are excellent.

      Military models have decryption software (basically a 3DES chip, I believe) which can listen to the encrypted channels broadcast by the birds but from what I understand, the MAIN DIFFERENCE is that military models have a more accurate clock than the civilian models. Because of this, even with SA disabled, they get triple the accuracy with 7 fewer channels.

  6. It's even easyer than that... by TheMidget · · Score: 2, Insightful
    If the enemy cracks your transponder codes, they can easily target you.

    Or, even easyer:

    If a vehicle is captured, the system has a self-destruct mechanism that can be triggered remotely.

    Just crack that, and don't waste any of your precious ammo...

    1. Re:It's even easyer than that... by gailwynand · · Score: 4, Informative

      Many military radios can do frequency hopping - changing frequencies many times a second. So unless you have a similar device AND you know the algorithm, AND you know the starting frequency, AND you know when the radios were turned on...

      Come on, I know someone works in a Comm MOS and can 'splain it better ;-)

      --
      A pilot, in those days, was the only unfettered and entirely independent human being that lived in the earth.-Mark Twain
    2. Re:It's even easyer than that... by feepness · · Score: 5, Informative

      Many military radios can do frequency hopping - changing frequencies many times a second. So unless you have a similar device AND you know the algorithm, AND you know the starting frequency, AND you know when the radios were turned on...

      I use to work on military communications. The version I worked on switched frequencies about 10,000 times a second. That was ten years ago. Not only is this harder to track, but even more importantly it's harder to jam. Keys were changed daily.

  7. Link it to a running Battlefield 1942 sim by blair1q · · Score: 2, Interesting

    Link it to a 3-D sim, and you can "play" the war in real-time.

    Add a joystick and some electric "prods" in the soldiers' uniforms, and you can literally play the war.

    --Ender

  8. Re:What is to stop a captured FBCB2 from being ... by humpTdance · · Score: 3, Informative

    Public Key Infrastructure & Cryptography

    Among a host of other military technologies that are in place to guarantee the authenticity of a user

  9. Mil spec by isomeme · · Score: 4, Insightful
    Kind of odd when I can 12 channels on my civilian model (with admittedly lower spatial accuracy).
    I'd also imagine that yours would be unlikely to continue working if, say, dropped onto concrete from fifteen feet up, or if a bomb went off ten yards away from it, or if it took a glancing impact from a bullet. Say what you like about US military gear, the stuff is amazingly rugged. Ten year old tech that keeps working under battlefield conditions is far more valuable to a soldier than bleeding-edge tech that quits if it gets damp.
    --
    When all you have is a hammer, everything looks like a skull.
  10. Friendly fire as happened long before today by MyNameIsFred · · Score: 4, Informative
    Friendly fire incidents have happened for a long time. The Pentagon estimates:

    WW II: 21,000 (16%)
    Vietnam war: 8,000 (14%)
    Gulf War: 35 (23%)
    Afghanistan (2002): 4 (13%)

    The difference today is instant communications. And the small number of total casualties allows the media to focus on each death.

  11. I have a question... by SirDaShadow · · Score: 2, Funny

    ...are the good guys in blue and the bad guys in red? ;)

    1. Re:I have a question... by tunabomber · · Score: 2, Funny

      Not unless everyone has their evil bit set correctly.

      --

      pi = 3.141592653589793helpimtrappedinauniversefactory71 ...
  12. Poor or incomplete research by MmmmAqua · · Score: 4, Informative

    From the article:
    The new system will also track all 12 G.P.S. satellites in each hemisphere at once. The old units can only track five satellites at once, and signals from four satellites are required to establish a three-dimensional position. In addition, current G.P.S. receivers are somewhat vulnerable to enemy equipment that beams false G.P.S. signals to indicate the wrong location, a technique known as spoofing.

    Here's the thing: the article is correct about the PLGR needing four locked satellites to establish a three-dimensional position. However, a PLGR can also establish a two-dimensional position with two locked signals and one intermittent one. The important part here is that the PLGR's most common use (determining position for individual soldiers and vehicles) doesn't need a 3D position. Your position (including elevation) can be plotted on any map using only two coordinates. 3D positions are only important for aircraft, air defense, and artillery. And for the most part, those guys aren't using PLGRs. Oh, and PLGRs can track up to 10 satellites.

    This corrective post brought to you by a US Army Cavalry Scout. (None of this information, by the way, is classified or restricted. The reporter just didn't check sources very well.)

    --
    Arr! The laws of physics be a harsh mistress!
    1. Re:Poor or incomplete research by Anonymous Coward · · Score: 2, Insightful

      A few comments:

      1) Four satellites are needed for a 3D position lock because the "fourth unknown" is exact GPS time. Receivers simply set up and solve a system of equations with four variables: x, y, z and "b", the receiver's clock bias. Solving the system of equations is an iterative and approximate process.

      2) Modern receivers will use as many satellites as are "visible" to them at any point in time. More sats means higher accuracy. Each satellite gets weighted based on its elevation - satellites close to the horizon hardly figure into the calculation.

      3) It is perhaps true that a 2D position can be achieved with just two satellites, if the third "intermittent" signal can provide clock (GPS time) calibration at sufficient intervals. Realize though that the accuracy will be SEVERELY limited since the receiver's clocks are vastly inaccurate and temperature-sensitive at the required time-scales. Furthermore, the position is actually a "circle" (intersection of two spheres) which, when additionally intersected with the earth's surface, will give you two possible positions. Usually one can be discounted based on other information. Each of these steps greatly reduces the accuracy.

      3) Biggest problem for the military is jamming (NOT SPOOFING) of the GPS signals. The GPS signal level is WAY BELOW NOISE, i.e. a very weak radio signal, and can easily be jammed across wide areas with low-powered jammers. Reportedly one such jammer operated in central Baghdad during the past weeks, causing some "smart" bombs to become "dumb". Reports that the jammer was located within the Russian embassy compound are as yet unfounded. The military uses additional GPS signals on a different frequency band, which makes jamming a bit more difficult.

      4) Second biggest problem is also related to the low signal-strength of GPS: receivers generally can get a good position fix anywhere in the open. Inside structures, or under dense foliage, however, GPS devices can become useless. Next generation GPS satellites will be broadcasting on two additional frequency-bands and at a higher signal-strength.

      From what I understand, the older military receivers may be very robust, but in past years a number of advancements have been made in GPS receiver technology, to improve on the points listed above and generally allow more accurate position fixes under more adverse conditions.

      Another important note: for many applications (including the one detailed in this story), relative positioning would due, or even be more appropriate. Using differential double-differencing GPS, the position of each friendly fighting vehicle can be determined relative to, say, the main comms vehicle. If in addition the position of the comms vehicle is well-known (using a highest-quality GPS receiver for absolute positioning; and preferably by keeping its location fixed for 15 minutes or longer, to allow for time-averaging out certain errors), then you will know the fighting vehicle's positions with MUCH GREATER accuracy then what's possible using their receivers for absolute positioning only.

      Such "double-differencing" relative positioning requires a data-link, and since this application already relies on this, it seems like a no-brainer. Maybe they already do this?

      Thoughts?

  13. military and gps by Anonymous Coward · · Score: 3, Interesting

    Just recently I had to give a presentation on Garmin, a GPS manufacturer. I mentioned that they don't really make military grade GPS's. But an individual in the class, who was in the military, said that many officers actually carry civilian GPS's in addition to the military ones. They're less accurate, but they're much faster than many of the military grade ones.

  14. Re:"shovels and cigarettes" by MmmmAqua · · Score: 2, Interesting

    That they don't call out "Smoke 'em if you got 'em" anymore.

    Actually, they do. I've taken smoke breaks in the middle of MILES firefights (while in good cover, of course), and after having my hip crushed in a training accident the first thing I asked the medic for (and got) was a smoke.

    I think you may find smoking is more common/acceptable in combat units than in REMFs. I don't know for sure about that, though, since I've been a Cavalry Scout for my whole career.

    --
    Arr! The laws of physics be a harsh mistress!
  15. Your really this niave? by Tailhook · · Score: 4, Interesting

    While some units have rather modern system that can graphically display locations of other troops, others rely on 10-year-old 5 channel receivers. Kind of odd when I can 12 channels on my civilian model (with admittedly lower spatial accuracy).

    The fact that some units are using a "10-year-old 5 channel receiver" does not surprise or concern me in the least. The military has prerogatives other than "latest and greatest nifty stuff" when procuring equipment.

    Those old units probably contain custom hardware to cope with un-obfuscating GPS signals for back when the signal was still (and could again) being obfuscated. Those devices survive generation after generation of soldiers who are expected to use the things in all combat environments. In other words, this is not some plastic Taiwanese el-cheapo GPS receiver you paid $300 for at wiggliesneatshit.com. Do you have any clue how much time and money it takes to build one-off mil-spec equipment in low volumes that the military routinely requires?

    I've actually found detailed technical information about the unit you're talking about. It's here and it's a damned interesting read. For instance, does your spiffy little 12 channel unit happen to have any anti-jamming/spoofing features? Exactly how many artillery shell concussion shock waves will your unit survive while your crew is firing the ol' 155mm? The DoD is so happy with the things they are trying to extend the warranty!

    The fact that some units have more modern equipment than others is a perfectly normal, healthy way to run a military. Some of you paying attention to our recent deployment to Iraq have learned that the Army's 4th Infantry Division has only just now arrived in theater. This happens to be the Army's "showcase" Division. If it's the latest, the 4th ID has got it. It's not that our government didn't want to deploy the 4th, but Turkey didn't cooperate and the whole outfit had to be floated around the Mediterranean. Basically, the most advanced ground force on Earth arrived just in time to become traffic cops. Meanwhile, the old fashioned 10-year-old PLGR units are probably exactly what the 3rd ID used to actually get the job done.

    You show me someone astonished by military procurement practices and I'll show you an ignorant fool. The next time you have the urge to compare your knowledge of equipment/technology to that of a military, just assume your wrong and shut up.

    --
    Maw! Fire up the karma burner!
  16. Re:bandwidth? by joggle · · Score: 2, Insightful
    You could store the wave form, but unless you could crack it quickly it probably wouldn't do you any good as nearly all of the info you could glean from the broadcasts are very perishable (time-sensitive). What good would it do you if you knew where your enemy was 5 weeks ago!

    Also, if the frequency is changing at a rate of 10kHz, simply doing a Fourier Transform of the signal probably won't help you much in trying to determine the true frequency at any given point in time, especially if you don't have a clue what the frequency changing algorithm or key values are.

  17. Re:For multiple units? by bugnuts · · Score: 4, Informative

    Slow? resource intensive?

    GPS uses triangulation, essentially, although it's a lot easier since it sends out a timestamp. To triangulate a unit, you would have to have 3 stations be time-synchronized and all would have to know they heard the same signal -- which is undoubtedly coded making it EASIER to know it was the same.

    In other words, tank A sends out an encrypted digital message of "here is my location". If 3 stations hear the signal and timestamp it to the nanosecond, they can them compare the signal--without knowing what it actually broadcast--and tell it was the same broadcast. Using the time data and and the exact location of each station, it's a simple matter to plot the location of the transmission. The farther apart the 3 stations, the better the accuracy. More stations would lead to more accuracy, plus you'd couldn't shut it down by bombing a single tower as long as 3 remained.

    This would essentially be a reverse-gps. It's only resource-intensive and slow if you have a single unit driving around with a directional antenna, like the FCC did to locate pirate stations. If you can synchronize the clocks and timestamp signals accurately, it's almost trivial to pinpoint the location.

  18. Exceed on windows, I bet. by SvnLyrBrto · · Score: 3, Insightful

    My guess is that it's an X11 Unix application being displayed on a windows box running Exceed to make it into a virtual X terminal.

    (Yes Virginia, the dumb terminal is alive and well.)

    Said configuration is so common it's almost obscene. My first Job out of college was at one of Lockheed Martin's many branches. All of the REAL work was done on various flavours of Unix (AIX, HP-UX and some other IBM OS in our case, and some projects in the facility were expreimenting with Linux and BSD as alternatives (Main problem being, VA and the like don't exactly build their boxen to MILSPEC, HP and IBM were happy to do so.) Obviously, we needed a Unix environment to program computers that would be rinning Unix in the field. Makes sence, right?

    Problem being, as they said on Star Trek: "The buerocratic mentality is the only constant in the universe". And LMCO has a BIG one. Some big muckety-muck, a CIO, an IT director, or somesuch, had chosen Dell as the desktop vendor for our facility, gotten several score truckloads of the things at bulk rate, built an NT-centric IT staff and 'standard desktop configuration', and said "Thou shalt use windows on thy desktop!". No matter that windows is completely useless to engineers. He's got his Dell/windows empire, and he's going to lord over it. So what we had to do, is run Exceed on the things to open virtual X windows onto the real computers, on which our actual work was done. This was supposedly a pretty common situation at the rest of LMCO as well.

    In the course of doing latter jobs, and interviewing for others, I've discovered that this is stupidly common within other government contractors as well, and not uncommon outside. So I've little doubt that it's pretty common in the actual military as well.

    I can't even BEGIN to imagine just HOW many windows PCs are out there, complete with Word, Excel, Powerpoint, Outlook, etc. etc. etc., all those licenses doing nothing but burning money; when the only purpose they wind up serving is as a glorified dumb terminal.

    (PS. Oh yeah... it's not too hard to change the graphic on the start menu button, startup screen, or most other places, so that's no indication that it's not windows.)

    cya,
    john

    --
    Imagine all the people...
    1. Re:Exceed on windows, I bet. by Minna+Kirai · · Score: 2, Interesting

      So I've little doubt that it's pretty common in the actual military as well.

      I doubt it strongly. If you worked for a defense contractor long, you know there is a HUGE difference between the equipment used in stateside research labs and what is deployable in the field.

      Software thats going to be run in actual military combat should always be compact, embedded systems code. We all know the story of the battleship running Windows NT, which only demonstrates why this is a bad idea- and the military is usually completely aware of this.

      As described in the story, FCB2B is run on armored vehicles on a real battlefield. And as I said in my post, it is insane to think that the designers of a vehicle like that would pack on 2 separate computers to run separate client and server. It's just as crazy to imagine that they would run a remote X11 application from a moving tank (secure bandwidth is very, very scarce), or that they would emulate Unix inside an emulated session on Windows.

      Slightly more probablye is that they're running a ported Unix program which still displays over a TCP (loopback) connection to an Xserver. The DoD has done this for some R&D applications (like older versions of EADSIM), but it still seems unlikely for something that'll be carried into battle.

      Besides, the icon on the bottom of the screenshot is a red X. Isn't Exceed's logo a green bird?

      Obviously, we needed a Unix environment to program computers that would be rinning Unix in the field.

      Even Unix is normally considered too newflangled and unpredictable to run in "the field".

      I can't even BEGIN to imagine just HOW many windows PCs are out there,

      Microsoft can give you some info if you really want the painful details.

      I've discovered that this is stupidly common within other government contractors as well, and not uncommon outside.

      Take heart, the goverment may be learning a lesson. Someday they may pull the defense contractors along with them. Until then, Lockheed and the rest will remain big Microsoft VARs.

  19. Re:What OS is FBCB2? by PortWineBoy · · Score: 2, Informative
    FBCB2 runs under Solaris on a Pentium PC.

    Sorry about not formatting this link.

    http://www.shai.com/papers/IITSEC-02-FBCB2.pdf

    Interestingly enough, the Army's most powerful tanks, the M1A2, don't run FBCB2, they run the older and incompatible system which I believe is called IFIS. The 3rd Division in Iraq had M1A2s with IFIS and the recently deployed 4th is outfitted with FBCB2. The 4th is considered the Army's most "wired" division.

    --

    this sig deleted by another sig