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Wireless Networking Communications Hardware

Cognitive Radios Could Increase Wireless Spectrum 90

schliz writes to tell us that a new intelligent radio technology, dubbed "cognitive radio," is being developed that adjusts operation based on input from its surroundings. Consumers wont likely see practical implementations of this tech for another five years, but it could have wide reaching applications from wireless networking to public safety devices. "Adaptive, cognitive radios could enable techniques such as dynamic frequency sharing, in which radios automatically locate unused frequencies, or share channels based on a priority system. In public safety, cognitive radios also could be used to provide interoperability between various signals and automatically adjust radio performance."
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Cognitive Radios Could Increase Wireless Spectrum

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  • by Anonymous Coward

    Share a scarce resource? Commie!

  • Maybe I'm cynical... (Score:5, Informative)

    by JustinOpinion ( 1246824 ) on Tuesday September 16, 2008 @09:02AM (#25024035)
    My initial cynical reactions are:

    dynamic frequency sharing, in which radios automatically locate unused frequencies, or share channels based on a priority system

    But as with any system of resource sharing (especially bandwidth), some devices/users will simply ignore the rules to improve their own performance: flag every transmission as ultra-high-priority and so forth. You can't expect users, or even manufacturers, to "play fair." And I'm not convinced that regulation can force people to play fair. Unlike objective measures like antenna transmission power, things like "priority" are more open to interpretation (or misinterpretation, if you prefer). I suppose the same solution as for cell-phones could be applied: if you charge someone for every transmission, they are forced to conserve bandwidth.

    In public safety, cognitive radios also could be used to provide interoperability between various signals and automatically adjust radio performance.

    I love technology... but when it comes to safety and emergency systems, it's usually best to use the lowest-tech solution possible: cheaper, easier to repair/maintain, more robust, more reliable, and better understood. I don't know if I want my emergency call negotiating interoperability with other devices to reach someone (since any such operation is error-prone). The simplest solution (e.g. full-power transmission on a reserved channel) is probably better in such a case.

    • by Nursie ( 632944 )

      My first thought too -

      Some manufacturer with little to know corporate responsibility will abuse this. Another with little to know corporate oversight of their dev department will break it accidentally (maybe by putting the new guy on it). Other people will abuse it deliberately in hard hacks. Open source hard/firm/software will make it adjustable.

      Bad plan, democracy, when half the expected device population is dumb and the other half abusive.

      • Random phrase misuse nazi info: Little to no. As in, little to none. As in, not very much! They may have little to know as well, but that's beside the point!

        • by Nursie ( 632944 )

          Cheers, I think my brain's going odd. I *know* that, but somewhere between brain and fingers it got lost.

      • by Enry ( 630 )

        Normally I'd agree with you, but ability to trample on other frequencies has always been around. The FCC comes down pretty hard on manufacturers that are out of spec (hence the reason why just about every electrical device sold in the US is tested to FCC specs).

      • by Alamais ( 4180 )

        I'm curious as to the possibility of adaptive abuse control if, in this 'cognitive' scheme, devices are communicating with each other about usage of the shared resource.

        For instance, if enough devices agree that some device is being a hog, they can first ask it to to desist, and second pull off some sort of DDoS (jamming, injecting garbage spoofed packets, whatev) to knock the abuser out.

        I've really no idea: is something like this possible?

        • by Nursie ( 632944 )

          I'm sure it's possible, but it sounds like a recipe for device warfare, not cooperation.

    • by Lumpy ( 12016 )

      But that's not the case. Most emergency services use the trunked 800mhz radio service that is complex as hell and relies on way too much supporting tech for them to work. They share the same band with fire,police,EAS,etc... but use the digital radios that are complex as hell.

      • They're not complex at all by today's standards. In fact, analog trunk systems use the same type of voting/priority receivers that have been used by repeater systems for 20+ years, but with the added benefit that the repeaters are continuously updating the radios (a few times per second) with the status of the system.

        Digital trunk systems are a bit more complex, but because of the compression used, they can fit more than one conversation into the spectrum normally used by one analog signal. All this tech

    • But as with any system of resource sharing (especially bandwidth), some devices/users will simply ignore the rules to improve their own performance: flag every transmission as ultra-high-priority and so forth. You can't expect users, or even manufacturers, to "play fair." And I'm not convinced that regulation can force people to play fair.

      This concern can be addressed with well defined standards, as has already been done with 802.11. While not perfect, 802.11 has proved quite good at producing devices that "play nice" with one another. But when those devices encounter non-802.11 devices the non-standard devices do tend to crush them. Fortunately, market forces are convincing people to replace non-802.11 with 802.11 in most of the applications where it works.

      However, there is another, technical, concern that presents a major problem for C

    • Re: (Score:2, Interesting)

      by nategoose ( 1004564 )

      I love technology... but when it comes to safety and emergency systems, it's usually best to use the lowest-tech solution possible: cheaper, easier to repair/maintain, more robust, more reliable, and better understood.

      I agree. Lately I've been thinking about the day when someone gets stranded on an island, actually builds a simple transmitter to ask for help, and no one can hear their plea because it's old fashioned analog radio. Oh, they die before someone finds them. It's sad.

      • Re: (Score:2, Funny)

        by Wescotte ( 732385 )

        Don't worry about it. Coconuts are set to go digital next year so it won't be a problem.

    • by dgatwood ( 11270 )

      But as with any system of resource sharing (especially bandwidth), some devices/users will simply ignore the rules to improve their own performance: flag every transmission as ultra-high-priority and so forth. You can't expect users, or even manufacturers, to "play fair." And I'm not convinced that regulation can force people to play fair. Unlike objective measures like antenna transmission power, things like "priority" are more open to interpretation (or misinterpretation, if you prefer). I suppose the sam

    • by Sammy76 ( 45826 )

      Actually, a lot of research has been done on this very question of "playing fairly" (much of it from a market-focused point of view), with some very ingenious schemes proposed. There can certainly be objectivity to these kind of schemes -- particularly if there's money on some end of the agreement.

      And for safety and emergency systems -- why should use phones and radios when the telegraph is so much more reliable and cheaper? Cognitive radios in this application space are currently being promoted as way o

    • by sahai ( 102 )

      O.k. It is not often that I will post using my real name, but this seems to be a suitable opportunity since Cognitive Radio is actually one of my main research areas. (On a day I have mod points no less. Ah well.)

      Here's the real deal:

      The problem of ignoring rules and how to deal with this is a real and very important problem. A public policy researcher named Faulhaber coined a nice phrase for this: "Hit and run radios." This is *not* something that only effects "cognitive radios," this is an issue that must

  • by Anonymous Coward

    My friend (who is in a position to know) says the problem with public safety communications is Motorola. They control the field (being the largest provider of equipment) and intentionally do not work well with others, Technology isn't going to be the solution to this problem.

  • This is not new (Score:5, Informative)

    by Gandalf_the_Beardy ( 894476 ) on Tuesday September 16, 2008 @09:07AM (#25024099)
    Motorola have been working on this for years and I suspect so have all the other mobile handset makers. Frequency agile, power agile systems are used in all cell phones, base stations can direct and use a focused beam to reach a faint handset - this is in service stuff. Walk through hand off from a handset that uses DECT, then dials out and goes cellular seamlessley has been demonstrated, as have handsets that can ask others to dial power down etc. The only thing holding this back has been market forces - customers just haven't wanted it. Yet.
    • How can one call "new" a 9-years-old technology? [ieee.org]
    • Well, there is a bit more to it than that. If you look at today's highly regulated frequency spectrum, it's really not very efficient. A lot of space for transmission ends up unused. Not only with respect to certain frequency bands, but also geographically. For instance, if you know that in your area the frequencies from 2.4 GHz up to 3.4 GHz are currently, right at this moment, unused, then why should your data transmission limit itself to the WLAN channel bandwidth? Or, if you know you will not need

  • Ugh not again... (Score:4, Insightful)

    by Andy Dodd ( 701 ) <atd7@@@cornell...edu> on Tuesday September 16, 2008 @09:08AM (#25024109) Homepage

    At least this one didn't make any "The FCC will be obsolete!" claims.

    As someone else said, there's not much to prevent rogue radios from abusing the system. Also, wideband receivers are extremely difficult to design. If you design an extremely wideband receiver, you give up one of the following:
    Low power
    Good interference rejection
    Low cost

    All the DSP in the world isn't going to help you if your receiver frontend is overloaded.

    • I'm not sure why a cognitive radio would be wideband, it could just as easily be a narrowband radio. It would be better if it could tune over a wide range of frequencies, or maybe just a few frequencies in several discrete bands like cell phones.

      The cognitive radio stuff I'm familiar with is on the military side, and I think it's mostly targeted at narrowband long-range comms that don't use fixed base stations. I don't think it's as applicable to commercial wireless networks that use a fixed infrastructur

      • Well, I could imagine that it's easier to make a wideband-capable radio transmit a narrowband signal than the other way around. Personally I'd rather have a general-purpose device _capable_ of transmitting and receiving ATSC video, say, and also transmitting SSB or PSK31. Clever DSP can make a wideband radio into (effectively) a narrowband one, but not vice versa.

        There's also UWB and spread spectrum to consider, as well as the ability for a smart radio to receive a whole band simultaneously, and present th

        • by Agripa ( 139780 )

          Clever DSP can make a wideband radio into (effectively) a narrowband one, but not vice versa.

          This is somewhat true however there are severe limitations outside of the scope of the DSP itself. In digital radio design, if the IF bandwidth is wider then necessary, then no amount of DSP can recover the performance of the narrow IF because no current sampling technology yields enough dynamic range to allow rejection of worst case adjacent signals. This is doubly true if you want the necessary high sampling rat

          • Very well put. That doesn't preclude switching in a narrow analog filter (a SAW or other IF filter) when you want the narrow band performance. If the filter has sufficient rejection, you could even use subsampling.
            • by Agripa ( 139780 )

              Very well put.

              I have been studying digital receiver design recently for a very similar application. Currently I am looking into how much processing power is really required for real time low latency digital demodulation with a sampled IF and relatively tame (or at least flat group delay) IF filtering.

              That doesn't preclude switching in a narrow analog filter (a SAW or other IF filter) when you want the narrow band performance.

              This is just what high performance receivers do. In some cases, there are selecta

    • I worked on a dispatching style radio for a customer that had several such products. One of those was New York taxicab drivers.
      He told me the way a cab is dispatched is by the blat-blat system. Basically the dispatcher calls out the location of a pickup, then all the taxicab drivers key down on their radios, which sends their identifier back to the dispatcher. The first guy in is notified that he is to pick up the customer.

      ...Extrapolate from there...

  • ...just get wireless routers to be 'channel agile' properly. This only seems likely to work at the carrier level of the infrastructure.

    • by Lumpy ( 12016 )

      only the current crap that became the standard.

      I have some ISA rangelan networking cars that are spread spectrum. they jump all over the band to share it very well and avoid interference. you cant select a channel because they use all channels.

      They were pre 802.11b and kicked the crap out of anything we have today.

  • by mazarin5 ( 309432 ) on Tuesday September 16, 2008 @09:12AM (#25024137) Journal

    Although it seems like a neat idea, in general, the article seems to have the stink of "buzz" around it.

    It's cognitive radio! It adapts, intelligently! If you go somewhere with a weak signal, your radio would get that signal some other way, intelligently! Wait, we mean broadcast towers would change their output and frequency whenever it gets crowded, and this allows things to be more crowded, but not in a bad way! The whole thing adapts, intelligently!

    I would love to see details, instead of vague descriptions about how things might work. Also, who profits, and how?

    • by elrous0 ( 869638 ) *
      I can't help but picture a cop yelling "I'VE BEEN SHOT! OFFICER DOWN!" into his radio and the dispatcher on the other end hearing "I'VE...switching optimal frequency...searching for signal...searching for signal...OFFICER......switching optimal frequency...searching for signal...searching for signal..."
      • by hysma ( 546540 )
        Actually it's more like the officer holds down the PTT button and hears a tone telling him his radio can't get a channel because they're all out of range or in use. This is exactly what happened with the CREST system they built here a few years back. It was supposed to be this great upgrade that put all the local police forces, fire crews and other public servants on the same system. Search for CREST in Victoria to find out all about the problems and how police offers had to resort to cell phones when in
    • Also, who profits, and how?

      That's easy. Professor Charles W. Bostian, the person highlighted in the article, very likely holds all the patents. How should be obvious at this point ;)

    • http://searchmobilecomputing.techtarget.com/sDefinition/0,,sid40_gci214574,00.html [techtarget.com] Used by the UK police very successfully. In service now. "In recent years, when European disasters have struck, emergency response teams from several European nations had a difficult time communicating with each other, due in part to the lack of standardization in their mobile radio equipment. The TETRA standards evolved to answer this communication challenge as well as others faced or anticipated by the European Commission
  • Dynamic allocation of frequencies has been around for quite some time, it's called a trunked system. [wikipedia.org]

    I guess the hype here is that they're using SDR technology to do it and a few neat tricks with wifi as well. Must be about time to sell the next generation of new radios to the gov/corp worlds.

    I tend to agree with the earlier poster who said simpler is better. At least having a simpler backup system seems reasonable here for the early adopters anyway.

    • by Sammy76 ( 45826 )

      We haven't been doing this for long because we haven't had fast enough A/D and D/A converters, and cpu speeds to handle the digital data. A trunked system is more of a radio application than a cognitive radio.

  • by mwilliamson ( 672411 ) on Tuesday September 16, 2008 @09:29AM (#25024319) Homepage Journal
    Uber high-end (such as Xirrus) Wifi-A/P's already turn their power down when needed. What is needed is a standardized and ieee ratified protocol so that an A/P can order its connected clients to lower their power as well. This allows for packing in more and more "cells" in a given area, thereby increasing the overall throughput. It also has a nice side effect of much extended battery life. (at least in cell phones/pda's...might not be significant with a laptop.) This is nothing new, and the cell-phone industry figured it out a long time ago.
  • I've seen these work in a test and development environment, although it was only slated to work in the typical 300MHz-3GHz environment. It's all fine and good when it is isolated from the communications systems of commercial services, it's when you start talking about roaming on other services that it really gets impractical considering the coordination of all the carriers that would be required.
  • by Froze ( 398171 ) on Tuesday September 16, 2008 @09:36AM (#25024399)

    The same concept has been in play for entire existence of Ethernet, which has proven very reliable. The only significant difference here is that instead of time based - single channel- collisions where you back off for a random amount of time, you back off and frequency hop.

    • It is actually more, you frequency hop and frequency aggregate. In addition, you change the rate and even communications protocol altogether.
  • Thanks but my Mom figured this one out in the early 90's when she asked me why he wireless phone couldn't become a cell phone when she left the house. I already have a cognative radio, its called a Nokia e71 and OMG it has Wifi and it is not asscrippled by Apple so it can have Skype, Google Chat, and putty all running at the same time.

    Lets ask the second why. OK not only do we not have to have single channel devices we now have fractal antennas and multi band chip sets and even peer to peer mobile devices [theregister.co.uk]

    • by cgenman ( 325138 ) on Tuesday September 16, 2008 @10:16AM (#25024945) Homepage

      Wow! One big cloud of spectrum. Damn those oligopolistic senators who are preventing us from reaching that utopia!

      Oh, and damn the people who make radio transmitters that can only recieve small slices of signal for a reasonable cost. Don't you want the cloud?!

      Oh, and damn the millions of legacy devices which all require fixed spectrum blocks without negotiation. Didn't they realize that the future was coming? Damn those applications where a DSP attached to your radio is impractical.

      Damn lazy americans who don't want to price-shop every time they make a phone call by looking for the reciever in their area with the lowest prices (or get trapped in an area where every reciever is gouging). Don't they realize that by checking cell tower rates every few seconds as you drive down the highway you can optimize your cash path?

      But yes, damn those Senators! Why don't they just back off from this entire thing and let natural market forces take over... by writing the millions of lines of new regulations this structured market would require, including the conversion of legacy devices (and their recycling), spectrum buyback, establishing interoperative billing communications standards, testing for aeronautical interference, etc. Clearly by not jumping on the "unlimited spectrum" utopia bandwagon based upon early technological progress and conjecture, they simply hate freedom.

      Why, why don't they realize that in areas untouched by federal regulation, like Operating Systems, the free market has created such perfect efficiencies? Why can't they enjoy the benefits of a truly competitive market like California's Energy markets?

  • In todays world most of the time in most places in most frequency bands there is no energy in the air, but it is still reserved for somebody. Even busy spots in city centers have a lot of radio energy only on limited bands in any given moment in time. There exists easily usable spectrum from 100 MHz to 5 Ghz. And it is trivial to pack more than one bit per Herz. The reason that we don't have gigabit radio communications is that a device certified to standard X can not use more than a tiny fraction of that

    • Re: (Score:3, Informative)

      by tlhIngan ( 30335 )

      In todays world most of the time in most places in most frequency bands there is no energy in the air, but it is still reserved for somebody. Even busy spots in city centers have a lot of radio energy only on limited bands in any given moment in time. There exists easily usable spectrum from 100 MHz to 5 Ghz. And it is trivial to pack more than one bit per Herz. The reason that we don't have gigabit radio communications is that a device certified to standard X can not use more than a tiny fraction of that s

  • There has to be some key or label that is shared before radio users can talk to one another. If that wasn't the case, Joe Blow could pick up a radio with this technology and start talking to the local cop on the beat.

    Interoperability of existing trunked systems for area-wide communications will make this work. We're doing it in Illinois with STARCOM-21. Price is an issue, but inter-departmental state-wide communications is now possible.

    For tactical operations, like at the scene of a fire or police actio

  • I didn't RTFA. I am thinking if we could revive the CDMA idea?

    Where every handset must adjust their own output, if they don't play nice, the base tower couldn't decode their signal and hence is no good to themselves either.

    • CDMA? Not sure I am with you here?

      There is no thing in CDMA that will prevent you from transmitting as much power as you like unless this is built into the system by the designer. Doing this is a design choice but has nothing to do with whether you are making a CDMA, TDMA, FD or any combination of these system.

      In CDMA2000 and WCDMA the systems are made with a power control loop similar to what is implemented in GSM. The base station will ask the handset to increase or decrease transmitted power depending

  • Implies far more intelligence than is actually going. Perhaps marketing hype.
  • Uh oh (Score:3, Funny)

    by Nerdposeur ( 910128 ) on Tuesday September 16, 2008 @10:14AM (#25024925) Journal
    Cognitive radios!?? Oh no you don't! (Starts adding layers to tin foil hat.)
  • "In public safety, cognitive radios also could be used to provide interoperability between various signals and automatically adjust radio performance."

    Interoperability is available today. Just choose compatible systems. Oh wait, will 'cognitive radio' solve the compatibility problem? Sure, if they cognite in compatible ways...

    Automatically adjusting radio performance sounds great. Let's see, AGC, AFC, spread-spectrum, oh, we already do a lot of that. I wonder what will be new or better...

    Sorry, call me

    • Interoperability in cognitive radio means heterogeneous radios (like between firefighters, cops, ...) should work together. How about a cognitive node that translates every message sent by heterogeneous first responders. The radio detects the presence of other radios (energy detection or feature detection) and talks to them in their spec (frequency, protocol, ...). BTW, software radio is a platform for implementation (of say cognitive radio, ...)
      • Cops have different radios than firefighters?

        In Maine, where I grew up, yes there were different channels or bands for local police & fire, state police, wardens, etc. But the radios were often virtually identical. Not easy to deal with.

        So, without reading TFA, how would 'cognitive radio' fix this? By tuning into the common frequencies, or changing channels? This is not possible today?

        Sounds like a profit mechanism to me.

  • Ya see, there's this one group - called the 'FCC'....

    Those bumbling buncha back slapping, hand shaking smilers can't even effectively legislate a bass-ackwards technology like BPL with out getting their dicks slapped to the dirt by a bunch of amateurs.

    How the hell could they ever re-write a hundred years of bandwidth/licensing regulations to allow for something effective??

    Death to tech by bureaucracy!!
  • Now if we can only get cognitive radio hosts and it will be worth something.
  • This has already been done.

    You can't "increase the amount of wireless space". Spectrum is a finite substance, the only thing we can do is figure out a way to share it more efficiently.

    The technology being talked about here is nothing more than a trunking system.

    Reference Motorola and Erricson's trunk system as well as others.

    --Toll_Free

  • Makes me poonwee [tinyurl.com].
  • Any one of us can experiment with this technology. It is not expensive and you can do it with home built equipment. What's happened here is that much of the functionality has moved from radio hardware into a computer. And a typical PC has enough power for this job. Google project names like "gnuradio" and "hpsdr" for leads on amateur projects. There are large on-line communities around several projects. If you want to transmit on higher power in is not easy to get a HAM license. You just pass an easy

  • Redirect (Score:2, Informative)

    by skjolber ( 933754 )
    As a telecommunications engineer, I do not understand what is new with this.

    If you want to check out something that will have a real impact on such video/radio applications, have a look at SVC [wikipedia.org].

    I have some printet material here from this year's IBC [ibc.org] where it seems NTT [nttdocomo.com] actually already have a software implementation of it.
  • The NTIA. http://www.ntia.doc.gov/osmhome/osmhome.html [doc.gov] They are the ultimate arbitrators of frequency spectrum management in the USA. That is because they work for the military and government agencies, who will never give up a single hertz of an incredibly valuable military and law enforcement resource on a PRIMARY basis.

    The FCC is second fiddle to them in practice, but the government does give lip service to the idea that the FCC works hand in hand with the NTIA. In reality its not true.

    For example, man

  • Cognitive? (Score:1, Insightful)

    by Anonymous Coward

    Maybe adaptive, but cognitive is horribly inaccurate.

  • Elements of cognitive radio are already in use, many of them for quite some time. A good example is adaptive power control: it's fundamental to the operaton of CDMA cellular telephony. As far as dynamic frequency selection, that's almost required if you're doing any sort of guaranteed-QOS work in the U.S. ISM bands (900 MHz, 2.4 GHz, 5 GHz). Examples here include Avnera's [avnera.com] wireless audio solutions (disclaimer, former employer) and Bluetooth's Adaptive Frequency Hopping (AFH). Avnera's system continually

  • Cognitive Radio (also known as "Opportunistic Spectrum Access") was first coined in an IEEE journal and is now considered the holy grail of communications research by many electrical/communications engineers.

    To understand cognitive radio one must first be familiar with software radio. The operating parameters of a traditional radio (center frequency, modulation type, bandwidth, etc.) are defined in hardware and static in type. A software radio is a device which, in affect, brings the "software to the a
  • June 2003 [slashdot.org]

    March 2003 [slashdot.org]

    June 2002 [slashdot.org]

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