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DARPA Funds a $300 Software-Defined Radio For Hackers 94

Sparrowvsrevolution writes with this story from Forbes: "Over the weekend at the ToorCon hacker conference in San Diego, Michael Ossmann of Great Scott Gadgets revealed a beta version of the HackRF Jawbreaker, the latest model of the wireless Swiss-army knife tools known as 'software-defined radios.' Like any software-defined radio, the HackRF can shift between different frequencies as easily as a computer switches between applications–It can both read and transmit signals from 100 megahertz to 6 gigahertz, intercepting or reproducing frequencies used by everything from FM radios to police communications to garage door openers to WiFi and GSM to next-generation air traffic control system messages. At Ossmann's target price of $300, the versatile, open-source devices would cost less than half as much as currently existing software-defined radios with the same capabilities. And to fund the beta testing phase of HackRF, the Department of Defense research arm known as the Defense Advanced Research Projects Agency (DARPA) pitched in $200,000 last February as part of its Cyber Fast Track program."
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DARPA Funds a $300 Software-Defined Radio For Hackers

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  • Antennas (Score:5, Interesting)

    by burning-toast ( 925667 ) on Monday October 22, 2012 @07:32AM (#41727069)

    Antenna design for this must be miserable...

    Anyone know if there is a good way to have relatively optimized reception over that whole spectrum without having to swap your antennas when changing frequencies?

    - Toast

    First post?

    • Re:Antennas (Score:5, Informative)

      by Muad'Dave ( 255648 ) on Monday October 22, 2012 @07:37AM (#41727089) Homepage

      Log periodic [wikipedia.org] or discone [wikipedia.org].

      • Re:Antennas (Score:5, Informative)

        by burning-toast ( 925667 ) on Monday October 22, 2012 @07:47AM (#41727145)

        I appreciate that. I might be heavily vested into computers, but radio isn't something I have had the pleasure to tinker with too much.

        Also, found the repo / blog for that board (article was lacking in details):

        http://www.greatscottgadgets.com/hackrf/ [greatscottgadgets.com]

        https://github.com/mossmann/hackrf [github.com]

        - Toast

        • The picture in the article thankfully had the URL on the PCB, so it's not like I had to play super sleuth to find it...

        • Re:Antennas (Score:5, Informative)

          by Muad'Dave ( 255648 ) on Monday October 22, 2012 @08:13AM (#41727271) Homepage

          You're welcome. Amateur radio folk have been on the forefront of DSP and SDR development for many years now. If you want to fool around with digital signal processing but don't want to invest in hardware, you can use the GNURadio [gnuradio.org] package, along with the GNU Radio Companion to create DSP chains using an IDE and signals to/from your soundcard or arbitrary sound files.

          For very little cash you can get a USB TV dongle that can be used as a signal source for GNU Radio. Search around a bit and you'll find sources - some are mentioned on the GNU Radio site.

          If you're interested in doing DSP/SDR 'for real' over the air, consider getting a Technician-class Amateur radio license. You have all privileges above 30 MHz, and can do really nifty stuff. No Morse code required anymore - all theory and regs.

          • by Anonymous Coward

            No morse code required for ANY license, including HF privileges.

            I don't know that i would say that amateur radio is at the forefront of SDR and DSP, or has ever been. Yes, people holding licenses are doing forefront work, but they're getting paid for it, not doing it as a hobby. Amateur radio triggered some of the very inexpensive SDR approaches out there (SoftRock), but that's nowhere near state of the art in SDR.

            And, in terms of software engineering for SDR, I would say that amateur radio, in general, i

          • by Anonymous Coward

            I have one of the super cheap rtlsdr dongles, and I'm in the process of making a discone antenna. Thus far I've been swapping dipole designs I threw together in the living room.

            It's good fun. I'm not a radio guy, but it's a great way to start with something you know very little about on virtually no budget.

            Highly recommend it for anyone that wants to tinker, but doesn't want to spend a lot of cash.

            http://hackaday.com/2012/05/14/improving-a-software-defined-radio-with-a-few-bits-of-wire/ [hackaday.com]

      • yes, that is the reply my University education in the early 80s taught. But something exciting happened in the late 1988, Nathan Cohen of Boston University made elements of a category of antenna called "fractal antennas". Certain fractal antenna radiate equally well over all frequences, at least theoretically. It was then realized that log periodic was a fractal antenna design.

        http://en.wikipedia.org/wiki/Fractal_antenna [wikipedia.org]

        • I'd heard of fractal antennas, of course, but I don't think they're widely available (other than LP's, as you mentioned). Here are some pics of the largest LP I've ever seen [hal-pc.org]. I'll be seeing it again next week. :-)

          • actually, they're in most cell phones now, that's where the antenna went! all manner of interesting patterns are employed, some look like snowflakes, some triangles within triangles, some like insects.

    • Re:Antennas (Score:5, Informative)

      by Chrisq ( 894406 ) on Monday October 22, 2012 @07:42AM (#41727121)

      Antenna design for this must be miserable...

      Anyone know if there is a good way to have relatively optimized reception over that whole spectrum without having to swap your antennas when changing frequencies?

      - Toast

      First post?

      This appears to be an area of hot research. Ideas include switch band antennas [ittelkom.ac.id] and Software defined antennas [wikipedia.org].

      • The wiki article on SDA is a bit slim - this is basically a phased array with many small elements, right?

        Hmm... how about using TFT manufacturing to create a huge array of elements, each with a transistor and a varactor? Dunno if you can make decent varactors with standard TFT tech.

        • Some plasma antennas feature low insertion loss (http://en.wikipedia.org/wiki/Insertion_loss) and capable of replacing conventional switching technologies RF MEMS or RF switches (PIN Diodes or FETs). The technology gets cheaper with increased frequency, which is a big plus. There are stealth and wide-band surveillance applications. Would love to play with one.
      • We're abstracting everything these days as soft-objects. Soon it will be Software defined Consciousness. The Singularity approaches! :)
    • Re:Antennas (Score:5, Informative)

      by vlm ( 69642 ) on Monday October 22, 2012 @07:49AM (#41727153)

      You need an app that requires coverage from 100 MHz (why not down to 75 MHz for international FM broadcast band RX? Only need down to 87 or so in the USA..)

      Usually wide band antenna design is not much of an issue in RF projects at the higher frequencies. Its pretty hard to make a dipole that covers the entire ham radio 3.5 to 4 mhz band than to cover a much smaller octave range at microwave bands.

      Also "relatively optimized" is kinda non-specific. My antenna for 2M is optimized for clean pattern first and gain second and bandwidth a distant 3rd... I don't believe it can be used above 145 MHz or so. Which for my use is perfectly OK.

      A "good" example of an antenna optimized for wide bandwidth would be an old fashioned VHF-lo thru UHF rooftop TV antenna. Miserable gain but crazy almost 10:1 frequency range.

      • by fyngyrz ( 762201 )

        (why not down to 75 MHz for international FM broadcast band RX? Only need down to 87 or so in the USA..)

        One thing about FM broadcast is that it's unusually wide-band compared to most signals, television excepted; many of the inexpensive SDR's can't provide that wide-band a signal. The FunCube, for instance, is good to 96 khz, which doesn't cut it. SDRs that are designed for SW or ham radio often provide even less bandwidth, as they're designed with 10 khz AM SW channels and 3 kHz sideband in mind. Or CW, w

    • For receiving only, a long-wire antenna should work fine.
    • by Mashdar ( 876825 )

      Anyone know if there is a good way to have relatively optimized reception over that whole spectrum without having to swap your antennas when changing frequencies?

      A general answer would be fractal antennas:
      http://en.wikipedia.org/wiki/Fractal_antenna [wikipedia.org]

      Log Periodic antennas are a subset of fractal antennas.

      Since they are fractal (ie scaleless), you can expand them to pretty much any wavelength range you need.

    • Actually you cover the whole band with two off the shelf double ridge horn antennas, one covers 100 MHz to 1 GHz and the second covers 400 MHz to 6 GHz. The 400 MHz to 6 GHz antenna is fairly portable, less than 20 inches (50 cm) in any dimension. I strongly prefer horn antennas for experimental work for safety as they have a strong and obvious directionality. Discone and related designs such as Bicones have a doughnut mode (no directionality in one plane) and log periodic antennas can have unexpected spike
  • Is this really "software-only defined radio"? Doesn't the radio need different hardware for different types of radios? Different antennas for different frequencies (and signal amplitude ranges in those frequencies)? Different analog for RF conditioning and glue from (different) antenna to logic?

    Or maybe a single "multi-antenna" with generic RF analog circuits can serve any radio. Isn't that a lot more expensive?

    If I want my receiver to do say WiFi right now, but switch to Zigbee later, and to Enocean after,

    • by Muad'Dave ( 255648 ) on Monday October 22, 2012 @07:55AM (#41727191) Homepage

      If you have SDR equipment that can operate on 2.4GHz and has enough bandwidth, you could operate WiFi, ZigBee, and other protocols at the same time. You could have WiFi on channel 1, ZigBee on 11, etc. As long as the chipping codes don't collide, you can go nuts. As an example of relatively simple SDRs, check out these Web SDRs [websdr.org]. These are single radios that digitize large swaths of spectrum. Each web user gets their own software virtual receiver that is tunable across the sampled spectrum. These radios can support hundreds of users at the same time, each listening to different freqs in different modes.

      The radio hardware remains the same. The parts that can change are external to the actual 'radio' part - preselector filters, preamps, antennas, etc. Once you get the signal of interest to the radio, the processing is identical. Look around for descriptions of I/Q modulation - by supplying in-phase and quadrature signals, you can generate any modulation you want.

      • I worked for a company that produced a software-controlled radio base-station. You have to know the secret to these devices: they can't actually cover more than 10 MHz at a time. There is a 10 MHz (or maybe a little better) band-width Yig that can be set in software to any given frequency between say 100 MHz and 6 GHz. This Yig limits sending and receiving channels to within 10 MHz of each other. Since Wifi channels are about 20 MHz each, your use case is not feasible. You could only use one channel at a ti

        • That was your use case - for many other uses, YIGs are unneeded - a simple NCO/PLL will work just fine. There are plenty of A/D's that can sample more than 10 MHz at 16+ bits. For the 2.4 GHz use case you would not have to sample the RF signal directly - that would be silly. You would first downconvert the desired signal to a more reasonable IF (intermediate frequency) and then sample that. If you don't have image rejection requirements you could shift it to DC and sample that. Read up on superheterodyne re

    • by ledow ( 319597 )

      This is, I think, the last barrier to myself literally just buying an SDR to tinker with. I know nothing of radio beyond simple physics and all SDR's that I see have various antenna/tuner/amplifier/whatever-they-are stages that cater for different frequencies. I keep going back to things like GNU Radio to see if they've got something for me, but it's all prototypes and "just add your own antenna worth more than my car".

      As such, it's out of my tinker-budget because I can't justify spending that money on so

      • You do realise that the $11 USB DVB-T dongles do about 75% of what you want? Sure the software still needs a bit of work, but the hardware is already able to receive many of these signals, and if you're willing to use a different program for each signal type, many of them can already be decoded. Sure you can't transmit anything yet in this price range, but there's a lot of stuff to listen to.

        Funnily enough right now I'm half way through planning a Wireshark style program very similar to what you descri

    • My (layman's) understanding is that that varies: Given that all real components have various limitations and finite performance, nobody sells a 'DC-to-daylight' frequency range in a single package, just not in the cards. Some SDR products are explicitly modular [ettus.com](see 'Daughterboards Table' tab), some, generally in exchange for lower cost, support a single slice of spectrum and hope that your area of interest falls inside it.

      This is a lot more expensive. This is why $300 is cheap for an SDR; but $30 is expensi

      • by vlm ( 69642 )

        This is why $300 is cheap for an SDR; but $30 is expensive for a wifi dongle.

        $21 is cheap for a SDR... kit. I built this one for 30M band back when it was about $12. If you are lucky you can get the correct assembled TV dongle off ebay for $10 or so.

        http://fivedash.com/ [fivedash.com]

        At the other end, if you'd like to spend four figures for cutting edge performance, there's always

        http://www.flex-radio.com/ [flex-radio.com]

        • Interesting. I have one of the little RTL2832/E4000 dongles plugged in right now, and I'm familiar by reputation with the USRP stuff; but my knowledge of the midrange, and any of the gear that has evolved from the hobbyist radio side, or that is designed for crunching RF down to something that a soundcard works with, is pretty much zero.

    • With just an ADC you can produce any kind of modulation. You're limited in bandwidth by the sample rate, which I assume is adjustable. You're limited in out of band emissions by the precision and the converter design.
  • by Razgorov Prikazka ( 1699498 ) on Monday October 22, 2012 @07:37AM (#41727087)
    I don't have a lot of knowledge in this, but it seems to me that one should be able to crack scrambled comm's much more easy right?
    Eavesdrop on GSM's, listen out on dect-telephones for example? Or 'tinker' with that new 'smart-meter' the neighbours had installed.
    Just some suggestions... not saying you should, but you could ;-)
    Sounds absolutely interesting!
    • by ledow ( 319597 ) on Monday October 22, 2012 @07:54AM (#41727179) Homepage

      The point is that you've always been able to do that. Radio hams have been building radios and you've been able to buy scanners that will let you listen and transmit on any frequency you like for decades.

      That's part of the article summary - people STILL using "security by obscurity" because they don't expect people to bother to record, modify and playback openly-available data is LUDICROUS. See the article just now about being able to scam public transport because of homebrew-encryption used over the airwaves.

      The problem is not the airwaves, or the devices available to read them. They've existed since Marconi, if you had the brains. It's that people still deploy systems where the wireless part is treated like some mystical, magical medium that stops people doing things to it.

      You can already listen to GSM. Radio hams found and cracked the encryption on it before it was even standardised. 3G technologies have similar problems. DECT, also. Smart-meters, some of them too. The problem is relying on untested encryption or no encryption/authentication at all in order to make things work and then being shocked when someone clones your phone.

      This is nothing new. It just makes it slightly cheaper and more convenient.

      • I know that this was possible already, but my suggestion is that it is more easy now than it was before. Just as you answered: yes it is.
        There must be millions of interesting things to receive, things that one would (normally) never even think of.
        For example these RFID locks on the company's door here. It must be quite interesting to check that out, see if there is a difference in 'fingerprint' between the several different doors that keep people out of areas where they dont need to be.
        And no, I dont (neces
    • We've already seen at least one successful brute force method to retrieve P25 encryption keys [slashdot.org] via GNU Radio..
  • by Anonymous Coward

    Good. Now we have a backup plan just in case government or industry tries to shut down free communications through the net.

  • Is there a SDR project for Linux that implements some of the circuits in FPGA?

    How about SDR where some of the RF analog is implemented in FPAA (analog array)?

    • The Ettus Research USRPs all appear to include FPGAs onboard, as does the Per Vices Phi device. I'm less familiar with the rather higher priced Serious Commercial Offerings; but it seems to be a pretty standard feature for allowing the user to do some amount of the heavy crunching before handing off to the CPU.

  • by eyegor ( 148503 ) on Monday October 22, 2012 @07:44AM (#41727125)

    Software radios are becoming more popular in the amateur radio community. There are several manufacturers of very fine radios and quite a few build-it-yourself radios available too. I'll be watching this with great interest since one of the biggest problems with the lower-cost software radios is band coverage.

    As Toast said a moment ago, antenna selection would be hard. Most radio amateurs would use an antenna tuner and/or a multiband antenna for the HF frequencies and an antenna switch for other bands of interest. I do just that. I have a 40 meter full wave horizontal loop antenna and use an antenna tuner and a 4:1 balun and can transmit on all bands from 40m through 10m and have very good results. It's also usable on 6m, but have never had a lot of luck with any kind of distant contacts.

    • by vlm ( 69642 )

      quite a few build-it-yourself radios available too

      The device announced is basically equivalent in specs to the couple years old UHFSDR (not a terribly creative name) as seen at

      http://wb6dhw.com/For_Sale.html#UHFSDR [wb6dhw.com]

      Main difference is this board has a 8-bit 20 Msps A/D onboard and the UHFSDR has it offboard (assuming you'll use a "16" bit 44+ Ksps soundcard)

      You can see quite a difference in implied project design here.... Is it even possible to pass FCC regs for IMD trying to transmit a 8-bit SSB signal, and obviously a audio soundcard doesn't sample wide en

      • by tlhIngan ( 30335 )

        Main difference is this board has a 8-bit 20 Msps A/D onboard and the UHFSDR has it offboard (assuming you'll use a "16" bit 44+ Ksps soundcard)

        You can see quite a difference in implied project design here.... Is it even possible to pass FCC regs for IMD trying to transmit a 8-bit SSB signal, and obviously a audio soundcard doesn't sample wide enough to do wifi or whatever fast digital stuff you'd like. So its broadband digital strong signal type of toy as opposed to something like a UHFSDR which is the opp

  • by petes_PoV ( 912422 ) on Monday October 22, 2012 @07:50AM (#41727157)
    Rather than spend $300 I think most people use RTL2832U/E4000 based TV tuners. Typically these have a tuning range from 60-ish MHz up to 1 - 2 GHz depending on the specifics of the design.

    Sadly, the chips used are getting scarce these days so the price of the products (available from your favourite chinese website) is going up. But it still beats $300 by a long, long way.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      They can't transmit though.

      • They can't transmit though.

        That's correct. Although since it's illegal to own a transmitter for frequencies you don't hold a licence to transmit on (and nobody holds a licence to transmit on "from 100 megaherz [sic] to 6 gigaherz") these proposed SDRs would have a big problem getting any sort of electrical conformance/approval certificate for sale in most countries.

  • Another TOY SDR (Score:2, Informative)

    by Anonymous Coward

    Uses only 8 bit sampling which will severely limit the dynamic range. You might as well use one of the $30 RTL2832U/E4000 based TV tuners. DARPA throwing them $200,000 for the effort is a WASTE of taxpayer's money for these guys to build a 'TOY' SDR!

    • by mc6809e ( 214243 )

      Uses only 8 bit sampling which will severely limit the dynamic range.

      In my experience, anything more than 8 bits per sample is a waste. It takes a very quiet em environment and input amp to reliably resolve more than 8 bits. Besides, most of the dynamic range is already handled by an amplifier with programmable gain.

      MUCH more important, IMO, is input bandwidth, especially in an environment where a signal can suffer from a lot of reflections. Your 16 or 24 bits per sample is useless if the narrow band you'

      • I guess that having a high dynamic range can be useful if you are sampling at a large bandwidth: in such a case you will probably be receiving multiple transmissions, if you get a very strong signal and a very weak one, how are you correctly going to sample them simultaneously? Compare it with HDR photography: normally you'd say it's overkill, but it does allow you to see detail in darker regions in an otherwise bright photo.

        However, you are correct in that you can increase the resolution by downsampling (d

  • by FudRucker ( 866063 ) on Monday October 22, 2012 @09:06AM (#41727699)
    I would not want it if they were giving it away free, it is junk without HF/Shortwave & SSB
    • by Anonymous Coward

      Check out AFREDRI SDR. Well under $300 shipped and features 0-30Mhz, 1300 Khz bandwidth, and both usb and ethernet.

    • Why is it junk without HF? I thought the primary purpose of SDR was to deal with wide(er) band digital signals, and most of them are well above HF. If you really need HF, there are plenty of upconverters that bring HF up to 100MHz+ so most SDR devices can receive the signals. (I don't think any of the current crop let you transmit though, since none of the current cheap SDR devices can transmit.)

      Also SSB is done in software, so any SDR can do SSB on any frequency.

  • Now....if we could use that thing as a real time spectrum analyzer, wed be in business.

    Until then, SDRs arent that impressive. Ill take my AOR 8200 MK-III and NRD 535D over SDR any day.

    • The whole point of an SDR is that it is inherently a "real-time spectrum analyser". You snarf down a large chunk of band, do an FFT on it, and display the spectrum.

      Take a look at this screenshot [gjcp.net] showing a 48kHz-wide chunk of the 40m amateur band. It's only limited to 48kHz because that's the rate I was sampling at. I could go wider by sampling at a higher rate, or I could "fake" it by using the same technique that "conventional" spectrum analysers do by tuning the centre spot up and down.

      • Uhm, I don't think that's what he means.

        He probably refer to a real spectrum analyzer (these costs in the range of 10K towards 250K) which essentially can display a whole frequency spectrum in one go on the screen, represented as curves (not the garbled graphics dot hell your screen shot shows)

        Here's a typical spectrum analyzer view: http://www.radaufunk.com/pictures/hp8569b/hp8569br.jpg [radaufunk.com]
        The curve in the image COULD represent a signal found at ex 300 MHz, and the curves size could represent the bandwidth the

        • I wrote an SDR display widget that shows the output as a spectrum analyser trace instead of a waterfall, but it wasn't as useful as a bandscope. It's a Small Matter Of Programming.

        • Oops, hit post instead of preview.

          Anyway, scanning from 100Hz to 2GHz in 20ms really isn't going to happen, because there's just no way to generate a sensible sweep that quickly. You're either going to miss massive chunks, or scan slowly. There are a lot of tricks you can use (DDS, "magic number" synthesis) to speed up the lockup time but it's nontrivial to scan any wide bandwidth like that.

          I'm not sure why seeing DC to light on one screen would be terribly useful, anyway. How wide would a single SSB or

  • What was written under the blacked out mark?
  • The next mayor improvement would be if that device was syncable . That way you could set up multiple devices and do MIMO. That's just a tiny thing, but could make a huge difference.
    Also ditch that USB port. If you have ever used an USRP you can see that it's mayor flaw is the USB port which is just to slow and unreliable to do anything useful with it. Use Ethernet.

The Macintosh is Xerox technology at its best.