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Handhelds Hardware

DoD Dreams of Efficient Spectrum Usage 135

Posted by michael from the spectrum-spectrum-everywhere-and-nary-a-drop-to-drink dept.
Unstrung writes "US Military research agency DARPA is sick of all those static-filled cellphone calls and dropped connections too. The shadowy eggheads are working on a way of using the bandwidth available today more efficiently."
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DoD Dreams of Efficient Spectrum Usage More

DoD Dreams of Efficient Spectrum Usage

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  • this just in... (Score:5, Funny)

    by red_five_standing_by ( 582037 ) on Friday July 26, 2002 @04:45PM (#3961693)
    DoD reports that they have fortified the radio spectrum with "stuff" for more "goodness." They declined further comment.

  • Doubt it. (Score:5, Funny)

    by smittyoneeach ( 243267 ) on Friday July 26, 2002 @04:46PM (#3961702) Homepage Journal
    After ten years active duty, and one in the Reserves, I can attest that the DOD has few, if any, dreams of efficiency. Keep trying.
    • Five years here... And I agree with you wholeheartedly.
    • I've got to disagree a little. Overall organizational efficiency as a business sucks. We feed the military a lot of money because we don't want them wasting all their time trying to save a buck here and there. That's how congressmen can get by with some of the idiotic spending mandates.
      Efficiency of systems, however, is something they excel at. For example, if a fighter jet is very inefficient, it's a dog, because it's either super-short range, or flies like a cow because it's carrying so much fuel. They package he food efficiently for foot soldiers so they can go farther, faster, with more ordnance.
      More efficient use of spectrum means more data. Don't confuse efficiency with penury.
    • I'll agree with you on one point, and disagree with you on another.

      DoD spent money and manhours = embarassingly inefficient
      DoD products = highly redundant, bullet-proof, and fairly efficient

      generally speaking, of course.
    • Yeah, sounds like a shell game to me.
      If more efficient spectrum use is really the goal then all they have to do is go visit their friends in the Department of Commerce who are trying to force the FCC to restrict 802.11a to indoor use only. I think it's safe to assume that the current administration is decidedly anti-wireless for some mysterious reason probably related to --cough-- national security. That's probably why Taiwan already has such restrictions. It certainly wouldn't have anything to do with protecting monopoly telecom interests.

  • DOD, DARPA and Inovation (Score:4, Interesting)

    by haz-mat ( 8531 ) on Friday July 26, 2002 @04:54PM (#3961742)
    The DOD and DARPA have a long history of bringing about technical innnovation, regardless of how slowly it comes into actual being, the very medium we are using (or abusing) right now is a result of that... unfortunately given the fact that i am at "work" right now, i can attest that they are not interested in efficency, mine is dropping like a rock... TGIF
    • They're the one's that implemented TCP/IP, and that's still in use today.

      I wonder if that's what'll happen with cell phones: people running their own Cell providers, just like TCP/IP services today.

      Pi

    • Re:DOD, DARPA and Inovation (Score:4, Funny)

      by craw ( 6958 ) on Friday July 26, 2002 @06:42PM (#3962200) Homepage
      The role that DARPA played in the "early" days of computing is often overlooked. DARPA funded the initial prototype development of something called the Stanford University Network workstation. IIRC, a guy by the name of Joy at UCB also received DARPA funding to enhance some of the capabilites of a "new" OS called UNIX. Eventually, the two efforts joined forces and produced a commercial product.

      RISC technology was pushed forward by DARPA. One effort eventually led to MIPS. Another effort led to the development of the RISC I and RISC II. This technology was licenced to Sun Microsystems, and eventually evolved into a more scalable architecture. I believe that this had some modest commercial success.

      Warp and the Connection Machine were the result of DARPA funded efforts to push forward and test the capabilites of massively parallel computers. These were technnological wonders, but did not achieve commercial success. At least, one of these was featured in a very successful motion picture. Furthermore, thanks to MIPS, probably the geekiest line in motion picture history was spoken, "This is a UNIX system. I know this."

      I would also have to speculate that a there are numerous computer industry leaders that had RA's in grad school via DARPA funding.

  • Well. (Score:3, Insightful)

    by Krapangor ( 533950 ) on Friday July 26, 2002 @05:00PM (#3961778) Homepage
    As far as I understood the article is that some dude got a research grant and the guy at the DoD thinks that he might get results eventually.
    This is nothing very expectional.
    People in research always get some grants and think that they'll get some results in some time.
    But often they get only one result: Is doesn't work. Or it does the same as the old stuff but more expensive.

    If often wonder if anyone has tried to get a grant for "the development of a disc-shaped flying object" yet.

    • Dude, Stop talking in NLP. (ERROR: No signature file was found.)
    • > If often wonder if anyone has tried to get a grant for "the development of a disc-shaped flying object" yet.

      If they do, they'll probably apply for a patent, and the US patent office will approve it. Then they'll charge manufacturers of frisbees with patent infringement. A call will go out for people who have knowledge of any prior art, but few people will respond, only a few geeks and we know how reliable they are. The frisbee manufacturers will attempt to show that they manufacturer their products before 2002, but the patent office and courts will have machines whose software treats all 2-digit dates as having an initial "20". As a result, the courts will conclude that frisbees won't be manufactured for another 60 years or so, and the manufacturers will be ordered to pay royalties.

      Hey, maybe I can turn it into a short story and get it published ...

  • GSM (Score:5, Insightful)

    by Zephy ( 539060 ) <jon AT aezis DOT net> on Friday July 26, 2002 @05:03PM (#3961787) Homepage
    Why not just convert everything to GSM? it works fine for the rest of the world. You never get static (digital transmission), and the call drop rate is a lot lower than analogue

    • Re:GSM (Score:1)

      by Caged ( 24585 )
      A GSM tower has far less coverage than analogue (about half), plus GSM just drops out at the edge of range. With analog you'd at least get scratchy reception.

      The only advantage of GSM over analog is that is (supposedly) harder to listen in on conversations. Although that doesnt stop those who really want to do so (criminal or otherwise).

      • Every advantage apart from the clearer calls, the faster data rates, the text messaging, the network roaming, longer battery life, more advanced phones, open international standardization and WAP (well it's not really an advantage, it's more a feature.. like.. a .. well. it's just there.)

      • Re:GSM (Score:2, Troll)

        by kevin lyda ( 4803 )
        yeah, those advantages plus the fact that i can use my gsm phone pretty much anywhere in the world except america. actually that works out well, 90% of americans don't have passports, and you'd have to be nuts to visit america as a non-citizen since you have no rights.

        • Re:GSM (Score:2, Offtopic)

          by forehead ( 1874 )
          you'd have to be nuts to visit america as a non-citizen since you have no rights.

          The almost trollish nature of your comment begs the question, What are the rights of non-citizens in other (non-US) countries? In the US, the constitution guaraneets certain rights for US citizens. The same rights do not necessarily apply to "outsiders".
          • "exception laws" for terrorist.
            I fear that now, if i buy a boxcutter (or worse, use SSH, encryption is for terrorist, u know)while visiting the US, i'll be jailed for life with no trial. That's why you have to be nuts to visit the US as a non-citizen.

        • Re:GSM (Score:3, Interesting)

          by Moridineas ( 213502 )
          Ok, I'm going to totally ignore your cell phone bashing which I'm sure others can refute better than I. However I have to make a point with the test of your message.

          You say that "90% of americans don't have passports". Let's check the data--I couldn't find anywhere a specific mention of how many passports in total are issued at any one time. however I could find press releases such as this one:

          http://secretary.state.gov/www/briefings/stateme nt s/970919.html

          Which state that:
          -In 1997 a record number of 6 million passports were issued
          -each year 40 million americas go abroad
          -in 1996 5.7 million passports were issued
          -each year since 1992 has seen more passports issued in 1992, in which 3.5 million passports were issed.

          So, we can assume that 40 million passports is the absolute floor number of possible passports. Also take note that many people who travel to other countries (Canada for instance, one of our two langbased neighbors in the US. Actually I just checked, and a border crossing into Mexico doesn't require a passport either) don't always have passports--I got into canada with a driver's license. So all those "international" travellers (of which there are a large number! don't always get passports).

          Also let's assume that since not everyone who has a passport goes broad every-year (and thus won't be represented in above 40M) that there are 30M who have passports sitting in a box at home. So we have a conservative number of 70M people with passports (I'm guessing the 30M is an under-representation).

          Also, on the web I read that around 16M people from the US visit Mexico every year. I couldn't find a number for Canada, but I'd bet it's similar. So right there we have 40M going abroad, and 30M going to other North American countries. That number alone is practically the population of Germany!! But anyway, disregarding Canada+Mexico (and also Alaska,Hawaii, smaller US islands etc, options most European nations don't have) somewhere around 1/4 of the population (population is around 270M) has a passport by my estimation, and enough people to roughly equal the population of Germany visit another country. And you're complaining about this why??

          This is just fud, fud, fud, us bashing.

          • Re:GSM (Score:1, Troll)

            by kevin lyda ( 4803 )
            passports have a 10 year life (at the most, you can get a 5 year passport if iirc). assume that 6 million passports were issued per year for the past 10 years. that's 60 million. at most. total us population is something like 350 million. let's make the numbers easy and say the population is just 300 million.

            so, with the numbers highly skewed in your favor, you're right: 80%, not 90%, of americans lack passports. so, 80% of americans can't easily go to countries with gsm - no great loss. and since non-us citizens can be brought before a military tribunal, it's probably not a good idea to go on holiday in the usa if you're not a citizen, so there's no need to be bummed about the lack of a gsm network.
            • http://www.cia.gov/cia/publications/factbook/

              Population is 278M.

              And as for a military tribunal, unless you're a terrorist, plotting death and destruction you have nothing to worry about.
            • since non-us citizens can be brought before a military tribunal, it's probably not a good idea to go on holiday in the usa

              What makes you think you have to come here to be brought before a US military tribunal? None of the guys sitting in cuba were in the US when they were captured. AFAIK everyone arrested inside the US in going through the regular justice system (Moussaoui, shoe bomber, who else?).
              • Padilla was arrested in the U.S., a U.S. citizen, and is currently being held incommunicado in a military prison. According to the justice department, they have no intention of even bringing him before a military tribunal, they're just going to indefinitely imprison him.

    • Re:GSM (Score:1, Troll)

      by Detritus ( 11846 )
      GSM has the worst spectral efficiency of any deployed digital cellular system.
    • I would suggest you skip the GSM and go for the next generation, 3G [3gpp.org], instead.
      Converting to GSM now then the rest of the world is just about to convert to 3G sounds... dumb.
    • I second that. God, static on cellphone calls? To quote, "that's soooo last Millennium.". Of course, the argument against it are the same, the infrastructure was already built and it's too expensive to convert (heck especially during this recession), so I guess these folks are doing the only thing that can be done, try and figure out to improve the analog phones.
    • GSM does not make very efficient use of spectrum - while it is very handy to be able to use my GSM phone almost everywhere in the world, most GSM operators are having to upgrade to the CDMA-based UMTS (aka W-CDMA) in order to use spectrum more efficiently.

      GSM works well, but suggesting it as a solution for spectrum efficiency is quite bizarre, particularly when cdmaOne (used by Sprint PCS and Verizon in the US) is more spectrum-efficient.

  • Interference Problems (Score:5, Funny)

    by Detritus ( 11846 ) on Friday July 26, 2002 @05:05PM (#3961797) Homepage
    Give me a couple of RDF (radio direction finding) stations and an 8" howitzer and I will eliminate all of your interference and congestion problems.
  • Bringing to terrestrial communications what satellite comms have had for years: Demand Assigned Multiple Access [qpcomm.com]. The article is a bit short on technical details, but it sounds like a very similar concept.
    • Also sound a little like a trunked radio system, the kind your local police and fire departments quite likely use. When your local emergency worker presses the push-to-talk button, the radio politely asks a central server to assign it a frequency.

      The article is *really* short on technical details, and even confuses directionality with frequency assignment.

  • BUZZWORD ALERT! BUZZWORD ALERT! (Score:3, Funny)

    by Dthoma ( 593797 ) on Friday July 26, 2002 @05:09PM (#3961825) Journal
    "These demonstrations will include demonstrating a low power/wideband spectrum sensor, time/frequency agile waveforms, and dynamic spectrum access and control."

    For all we know, this project description might actually MEAN something.

    • low power/wideband spectrum sensor
      The system wouldn't work without this bit. Low power = longer battery life. Wideband spectrum = plenty of frequencies to choose from (useful if you've got thousands of the phones trying to share the same set of freq's)
      time/frequency agile waveforms
      Time-agile just means the test signal won't just be a constant tone/periodic wave, but rather something more realistic. Frequency-agile means rapidly varying between Barry White and Mickey Mouse (or more realistic pitch changes, but you get the idea)
      dynamic spectrum access and control.
      ... is the whole point of the thing, AIUI.

  • Personal Privacy... (Score:2, Interesting)

    by Critical_ ( 25211 )
    What people don't understand is that with the system used by Arraycomm allows better precision mapping of the wireless user. Sure, these days with our current cellular system we can triangulate a persons coordinates but this system could allows on-the-fly tracking since its built into the system. This is something for you privacy expertst to chew on.
    • I think you mean global positioning satellites do that.
      • Actually I don't mean GPS. A persons cellular whereabouts can be triangulated with cell phone towers. I wish I had the webpage available.
        • Very easy with TDMA protocols, since timing is quite critical. The 'field engineer' menus on the average GSM phone will show the distance from the registered cell. All a network would have to do if there are multiple BSCs in range would be to bump from one to another and measure the response time on each to get a pretty accurate location.(Even with just two reachable in range you can tie down to one of two possible locations).

          Can be done with CDMA too but I suspect it's not so common (since unlike TDMA there are no timeslots to co-ordinate between different users).

          Pity the authorities don't make more use of this. If you ring the emergency services in the UK from a mobile phone, all the cellular operator passes on is the phone number you're calling from, not even the cell you're currently using. Could save a lot of time and trouble if they did.

          It's not all bad though. Location information can help prove you weren't somewhere just as easily as it can help prove you were somewhere!

          I don't think recording an _exact_ location is done as a matter of course, but it is common practice to keep track of the current registered cell (if only to save searching the whole network when there's an incoming call). In GSM the phones re-register periodically even if you don't switch cell so it's not uncommon to have the cell recorded every couple of hours.

  • My understanding is that part of the problem in the US is that the military is hogging much of the radio spectrum, much more-so than the military in other countries.
    • You want to know is the biggest spectrum hog in the USA? The television broadcasting industry. We could recover huge amounts of spectrum if we killed over-the-air television distribution.
    • The U.S. military is also the military for a large number of other nations. Most of Europe could not field a decent army if their lives depended on it.
      • Yeah, it's a good thing we've got you Americans fighting with us...I mean, who else is going to kill our troops?

        -Nano.
      • I'm sure the Europeans would be most impressed to learn this. I'm sure you speak of the present, otherwise I'm not sure what to tell the Royal Navy, Red Army, Prussian/German General Staff...et al.

        The Europeans don't field "decent" (I assume you mean large) armies because they don't need to. They do not conduct foreign policies that require substantial troop commitments. They don't have twelve aircraft carrier battlegroups like the US. They don't need them. Hell, we don't need them either.

        ~Chazzf
      • Europe doesn't maintain a large military because they don't need to, and if the US was smarter, they wouldn't need to waste their taxes on such things either. Hell, perhaps they might build a decent healthcare system instead. Which would you perfer?
    • If this program gets anywhere, it can help the military retire a bunch of the old equipment that's hogging lots of that spectrum, and replace it with more flexible stuff that's less expensive, and can reduce the extent to which they're blocking development of new technologies (ultrawideband, etc.) that might interfere with their hogged spectrum.

  • Ironically, I WOULD trust them more than any "joint industry task force" put together to decide how best to organize radio spectrum. I'd rather have a big portion that's mysteriously ignored by most new radios than have a sysem in place for charging by-the-second for a sweep across the newly-digital dial. :^)

    Ryan Fenton
  • I cant find a diagram showing how all the frequemcies are currently divided up. anyone havea link I can follow?

    We used to have a big poster of it on the wall at a VOIP company I worked at - know of an online version?
    • google image search found this one:

      http://www.jsc.mil/images/speccht.jpg
    • The big poster you speak of can be ordered here [fcc.gov].

      One caveat: I ordered one of these back in about February, and I only just got it a few weeks ago! I'm happy though because the US Government Printing Office gave me an automatic discount when it was slow. I must say the couple of quarters or so really helped defray that horrible $3.00 cost.

      Anyway, I'm home for summer and can't wait to get back up to school to see what it's like (it was shipped there, since I didn't count on such a long wait).

  • This is for the US military, dont expect your tax dollars to give you better phone calls personally.

    • Re:Military (Score:1, Insightful)

      by Anonymous Coward
      Where do you think hand held GPSs came from? Where do you thing the *internet* came from? They started out as big military projects and now you have them in your pocket. That happens with huge amounts of military research. Unless you are a slashdotter, in which case you are completely blind and ignorant, in which case you are right, you'll never see any benefits from this or any other DARPA research ever.
  • At least you know that when the military gets involved in something, endless piles of money are unquestioningly thrown at it.

    So, this can only be a good thing in the end.

    -Nano.

  • Sounds interesting (Score:2, Interesting)

    by hoytt ( 469787 )
    So what they're trying to do if I understand it correctly is to get the location of the person using the mobile and only tansmit the signal in his direction, unlike the normal 360 degrees done by other systems. It sounds nice, if they can do it. It would mean a lot less 'un-needed' signals through the air. It's like using a satelite dish for an uplink to the satelite.

  • Must be listening to George Gilder (Score:4, Insightful)

    by John Jorsett ( 171560 ) on Friday July 26, 2002 @05:41PM (#3961970)
    George Gilder has been talking about this for years. He gets your attention by making statements like, "available bandwidth is infinite." His basic point is that if the whole spectrum was available and if communicating entities continually adjusted their power levels and frequency to just what's necessary to communicate, the reuse of the spectrum could make it seem nearly infinite. I think he's probably right; I've seen some special radios designed on this principle, and their ability to communicate great distances with teensy power levels was nothing short of phenomenal.

  • What? Use CW? (Score:2, Insightful)

    by AX.25 ( 310140 )
    After all it is bandwidth efficient and is the most effective in low signal to noise ratio applications.

  • Not backward compatible. (Score:3, Insightful)

    by DraconPern ( 521756 ) on Friday July 26, 2002 @06:10PM (#3962072) Homepage
    This technology may be good for a spectrum where all the devices have the 'sharing' capability, but how are they going to make existing spectrum like the wireless network 'dynamic' without making everyone buy new equipment?
    • The military *does* like spending money on new toys, and Darpa's job is partly to design lots of new toys. So why was it you thought that "making everyone buy new equipment" was bad? :-)

      Cynicism aside, though, a lot of their existing communications tools are really expensive, and use old technology or newer technology that's made extra-complex to retain compatibility with older technology, and new equipment made with new commercially-viable parts can be *much* less expensive, often less expensive than maintaining existing equipment. For a computer example, compare the cost of buying a 1GHz 256M RAM 20GB disk machine today (about $400) with the cost of replacing fixing your 486 (which used different memory technology, EGA video, 5.25" disk drives, backup tape drives, no CDROMs, etc.) In some cases, the military does need militarized equipment (throwing radios around in trucks and dropping them off airplanes can be a bit rough), but often it's cheaper to buy 10 commercial units and have 8 of them break.

      • often it's cheaper to buy 10 commercial units and have 8 of them break.

        Sucks to be in combat and have one of those 8 units, though.

        In other words: get real.
        • Also sucks to not be carrying the MIL-SPEC ruggedized 5-pound GPS unit that only 5% of the soldiers are carrying because they're expensive and clunky - much better to be carrying the small cheap commercial version, and if it breaks, maybe your buddy's is still working. And it sucks even worse to be the guy flying the expensive surveillance plane getting shot at instead of the guy remotely operating a bunch of cheap drones even if they get shot down more.

          And remember all those M-16s jamming all the time in Nam? The commercial gun that the Army started with when they developed it was apparently much less likely to jam, but by the time it got kluged up into a more military-looking gun, it jammed more.

          • "And remember all those M-16s jamming all the time in Nam? The commercial gun that the Army started with when they developed it was apparently much less likely to jam, but by the time it got kluged up into a more military-looking gun, it jammed more."

            Err, no. The AR-15 was developed by a man named Stoner to BE a military weapon. Armalite may have released a commercial version of it first, but it was always a military weapon by design, with military, not sporting, priorities.

            As for the jamming, that was not a "military" design decision so much as a "DOD" design decision. McNamara decided that chrome plating the chamber of the rifle was simply not necessary and struck it off the specification to save a few $.01's.

            Although, what the hell - the guy has enough deaths on his tally; what's a few more attributed to technical ignorance?
    • You will need new kit, but real soon now it should be possible to implement 'software radio', in which you can download new software to implement whatever new radio interface someone has dreamt up. May take a few years, but in the longer term you could just download a GSM or UMTS module to your cell phone before travelling to Europe.

  • July 26, 1947 (Score:3, Informative)

    by totallygeek ( 263191 ) <sellis@totallygeek.com> on Friday July 26, 2002 @07:25PM (#3962335) Homepage
    You know that it is the Department of Defense's birthday? It is also the first day of the CIA.

  • If advanced(?) civilizations eventually spread their broadcast information content (e.g. cell phone calls) evenly across the radio spectrum, does that mean that if we were to tune into the radio emissions from such a planet (e.g., earth in 20 years as observed from the moon) that there would be no readily discernable signals, but rather the planet's radio signature would appear to be just a bunch of evenly distributed radio noise,-- since broadcasters would dynamically fill any frequency "holes" that might appear?

    Turning our attention to observing planets outside our solar system: would our current SETI searches be able to tell that such a radio spectrum represented information content? If not, how would a SETI search have to be organized to recognize this signature of a radio-active ;-) civilization?

    --Forgotten Password
  • i personally enjoy slapping sovietski sausage to paulina porizkova in company stall but would enjoy many new but too slow

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