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Universal Radio Grabber: the USRP 189

Posted by timothy
from the more-than-you-can-eat dept.
Nethemas the Great writes "The Universal Software Radio Peripheral or USRP created by Matt Ettus and Eric Blossom gives a new perspective on the radio spectrum, as in just about all of it from DC to 2.9Ghz. With the right software and daughterboards, their USRPs can capture FM, read GPS, decode HDTV, transmit over emergency bands, track peoples movement via their mobile phones, and much, much more. With prices starting at just $550 this new toy is accessible by most anyone."
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Universal Radio Grabber: the USRP

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  • The real question (Score:5, Insightful)

    by Umbral Blot (737704) on Monday June 05, 2006 @05:15PM (#15475484) Homepage
    The real question: how long before it becomes illegal to own or use one?
    • In the US it's not legal to have a device that listens in on certian bands, such as cell bands and military frequencies, and other than a few speicifc bands, you need a license for any transmitter. So the transmission components are almost certianly illegal in the US, at least to use. The reciever components, it depends on the range, and if the have holes where they should for given disallowed frequencies.

      Now this applies to the US one, other countries do not necessairly have an FCC equivilant that regulate
  • Ouch $550 (Score:5, Insightful)

    by 9mm Censor (705379) * on Monday June 05, 2006 @05:17PM (#15475498) Homepage
    I would hardly call _starting at_ $550 accessable to almost anyone.
    • Re:Ouch $550 (Score:5, Informative)

      by davidbro (13842) * on Monday June 05, 2006 @05:23PM (#15475559)
      Especially since it appears that the $550 gets you the motherboard, without any radio modules. The $550 will get you something that you need to spend more money on until it is functional. I think this is just a case of the journalist not really digging into it more than superficially, but the guy the reporter was talking to should have also pointed out how much a minimally configured system would cost.

      At a minimum you will need the motherboard, a radio module, some cable (which isn't cheap, especially for doing higher frequency work), and a useful antenna (those tiny ones they advertise on the website will be fine for higher frequencies, but if you want to do anything else, you are looking at an external antenna and more cable).

      However, this is a very cool project. A lot of good will come from this work. But $550 is not the starting price. The starting price is higher.
      • Note also that if you intend to do any FPGA programming with the USRP, according to this faq [ettus.com]you will need to spend and additional $300 to get 2 of each of the BasicRX and BasicTX boards for debugging purposes.
      • I'd by a Garmin GPS, a Yupiteru scanner and a decent FM/LW/SW radio (not Sony: DRM)
      • SCE head Ken Kutaragi was quoting as saying "It's probably too cheap."
      • $550 is cheap. Think of a lab setting, where you need equipment for every band you're investigating. That equipment is expensive; a grand is cheap! That's who this equipment is for.
      • Re:Ouch $550 (Score:4, Interesting)

        by stienman (51024) <adavis@BOHRubasics.com minus physicist> on Monday June 05, 2006 @09:22PM (#15476962) Homepage Journal
        For those that are curious, I looked up the cost of the components.

        Buying the chips in small quantities leads to about $100 just for the 4 main chips (two analog interface chips, one FPGA, one USB microcontroller). The PCB is likely to be around $20 if it's more than a two layer and in small quantities. The labor to assemble just a few of them is likely $50-$100.

        $550 isn't a bad price. But there's a reason the PCB isn't open sourced like all the other design files - the company wants (needs) to make money and recoup its investment.

        Still, one sufficiently motivated could reduce the cost of the entire board and probably include the popular generic modules to the $200 range if they were able to get a comitment to purchase from say 100 people.

        It's a neat concept, and one I'd like to get into, but right now it's not something that you use so much as tinker with. It's for researchers and hobbyists. Once there is real time hdtv decoder software in linux that runs with this, and a good tv/radio record/pause/skip program, as well as a nice simple scanner application then it will become something worth having for the general linux hacker.

        I think someone could make a good bit of money if they made a small module that just had one A/D interface, the FPGA, a cable modem tuner, and the usb microcontroller. It could sell for $100, which would be cheap enough for regular hackers to get it and start making really cool tv/radio applications for.

        -Adam
  • P2P Telephone? (Score:3, Interesting)

    by Mantrid42 (972953) on Monday June 05, 2006 @05:17PM (#15475501)
    My first thought on seeing this is, if it can simultaneously recieve and transmit, couldn't you create a truely decentralized telephone system? With the NSA wiretapping everything, isn't a simple solution to just take away the wires?
    • Re:P2P Telephone? (Score:3, Insightful)

      by CRCulver (715279)
      Amateur ("ham") radio operators have had a decentralized telephone network for almost a century. However, the FCC regulations governing transmission on bands accessible to the public require that no encryption be used so that the FCC and volunteer ham regulators can monitor activity.
    • Re:P2P Telephone? (Score:3, Interesting)

      by Wesley Felter (138342)
      If you want some sort of wireless P2P phone system, you'd probably be better off starting with a PDA with a high-power 802.11 card in it. SDR sounds like overkill.
    • Re:P2P Telephone? (Score:3, Insightful)

      by misleb (129952)
      Each device would need a unique channel and each device would need to be able to transmit the total distance bbetween any two phones. And that just makes wiretapping easier. For everyone, not just the NSA. Really, the simple answer to wiretapping is just encrypted VoIP. And if you want wireless, use a WiFi phone.

      -matthew
    • Re:P2P Telephone? (Score:3, Interesting)

      by Eravnrekaree (467752)
      I dont think using radio signals, instead of wires is really going to help your privacy much. How is transmitting something over the air where anyone can recieve it better than sending it over wires, which someone has to tap into physically?

      If you really want privacy, what you want is some really strong, good encryption. I would, if you are paranoid, encrypt your messages many times each time with a different key.

      People often claim wireless is the solution to everything. It definitely is not. RF spectrum is
      • How is transmitting something over the air where anyone can recieve it better than sending it over wires, which someone has to tap into physically?

        Radios don't have an IP address.
        • So what? (Score:3, Informative)

          by Slithe (894946)
          IP Adresses can be changed, and MAC addresses can be spoofed. If you are TRULY paranoid, connect to a random Access Point with a spoofed MAC address and talk using an encrypted VOIP connection. Simple, easy, and cheap (you can buy a laptop, microphone, and wifi card for less than the cost of the USRP motherboard.
  • How is this legal? (Score:5, Interesting)

    by Valdrax (32670) on Monday June 05, 2006 @05:18PM (#15475504)
    Aren't radio transmitters/receivers legally required to not be able to access certain bands without proper licenses?
    • by vinn01 (178295)
      I know that certain frequencies must be blocked by any radio receiver sold in the US.

      A friend of mine bought WinRadio from Austrailia in order to get the full spectrum version.

    • by prichardson (603676) on Monday June 05, 2006 @05:28PM (#15475591) Journal
      From their FAQ... http://www.ettus.com/faq.html [ettus.com]

      Are there any license requirement for the transmit or transecive daughterboards?

      The USRP is sold as test equipment, which has no licensing requirements. If you choose to use your USRP and daughterboards to transmit using an antenna, it is your responsibility to make sure that you are in compliance with all laws for the country, frequency, and power levels in which the device is used.
      • The USRP is sold as test equipment [...] If you choose to use your USRP and daughterboards to transmit using an antenna, it is your responsibility to make sure that you are in compliance with all laws

        Reminds me of a story I heard: during prohibition, you could buy a health drink that was basically grape juice concentrate. The instructions said something like "Do *not* dilute and certainly don't add yeast. If accidental yeast contamination occurs, don't even think about leaving it in a warmish place for ro

  • by drinkypoo (153816) <martin.espinoza@gmail.com> on Monday June 05, 2006 @05:21PM (#15475536) Homepage Journal

    Just the motherboard is $550. You will need at least one daughterboard to actually do anything. The cheapest ones (2-200MHz transmitter, 2-300MHz receiver, 30MHz transmitter, 30MHZ receiver) are $75 each. In order to just transmit, you will need to spend at least $625, unless you are a member of "TAPR, AMSAT, SARA, or SETI League" in which case you get $25 off the motherboard.

    Interestingly, though the sales page lists "extra" power supply, usb cable, and standoff sets, nowhere on the sales page does it actually say that the unit comes with any of these things. If you're going to run a business, run it right.

  • Homebrew SETI? (Score:5, Interesting)

    by superdan2k (135614) on Monday June 05, 2006 @05:21PM (#15475541) Homepage Journal
    Imagine a not-quite-Beowulf cluster of these -- your own homebrewed VLA. It'll receive in the "waterhole band" [daviddarling.info], and VLBI [wikipedia.org] ain't too hard to figure out. Set up enough ground stations and switch between them as-needed to compensate for what you're viewing and the rotation of the Earth, and you've got a fulltime radio telescope with a dish effectively as large as the earth, whenever you want it...

    Open source radio astronomy anyone?
    • We could call it... SETI@home!
    • Re:Homebrew SETI? (Score:2, Interesting)

      by patchvonbraun (837509)
      The Gnu Radio code used with the USRP already includes a couple of radio astronomy applications--one for spectral and continuum work, and the other for pulsars. Still very rudimentary, but the spectral application could easily be morphed into something more useful for SETI. Keep firmly in mind that doing amateur SETI observing with a small dish is a dicey proposition, at least based on the current wild-assed guesses for ETs radiated power budget :-) A flotilla of small dishes, all observing the
  • Who's got the rest of the software that combines multiple SW radios with phased arrays of smart antennas [wikipedia.org]? A mobile "phone" that can transceive in any band without any required registration (of frequency, time or code) because its signal is unique due to its unique spatial position. Bandwidth would be limited only by the power efficiency of the electronics.
  • Nothing new here... (Score:4, Informative)

    by Jizzbug (101250) on Monday June 05, 2006 @05:27PM (#15475579)
    It has been on the market since Nov. 2004.

    http://www.comsec.com/wiki?UsrpProgress [comsec.com]
  • by EW87 (951411) on Monday June 05, 2006 @05:28PM (#15475584) Journal
    Stalk Vida Guerra via cell phone...
  • by modmans2ndcoming (929661) on Monday June 05, 2006 @05:41PM (#15475679)
    It can not capture Zero-Point Energy, so it is NOT universal.
  • decoding HDTV? (Score:3, Interesting)

    by mackermacker (250587) on Monday June 05, 2006 @05:44PM (#15475708) Homepage
    Ok, I must be missing here (the details of HDTV were not very specific). Do other people NOT decode HDTV, and is that milestone? Any product by DVICO will also decode HDTV. My Dvico USB unit decodes it. All you need is an antenna. Granted, only local stations are picked up. But it doesnt matter, you can copy everything else too using other methods. Is he referring to cracking the RCE broadcast flag that certain HDTV channels have (INHD/INHD2 in certain areas?). Does my comcast box not already decode HDTV? I guess I don't fully understand the issue. Even if the RCE broadcast flag is set in the HDTV content, you can still plug in a firewire cable (at least in the Motorola/comcast boxes), and output to your workstation, capturing the raw .ts HDTV streams. All the ports are already open (as required by law), just no firmware for the boxes. YOu can even verify the active firewire using the command power-select-select, then going to section 11 and verifying the active ports changed from 0 to 1. Once you have these .ts streams saved, you can output back to your HDTV using DVI if you have it. And doesnt the RCE flag (again, required by law) require you be able to save it at least ONCE (common for pay-per-view on demand). In that case you capture it while it is playing, and you still get it. You don't have to respect the flag, it's up to the client (comcast). If they didn't though, they would loose all their advertising money. However, I don't know why a client on a workstation would need to repsect the broadcast flag. And if you are that interested in saving your HDTV content: http://www.avsforum.com/avs-vb/showthread.php?s=&t hreadid=353608&highlight=windows+xp+firewire [avsforum.com]
    • Re:decoding HDTV? (Score:5, Informative)

      by TheRaven64 (641858) on Monday June 05, 2006 @06:38PM (#15476127) Journal
      The Slashdot summary was monumentally bad. My first thought on reading it was 'this sounds like the kind of thing you could use with GNU Radio." Clicking on TFA, I discovered GNU Radio was in the article title. Strange how Slashdot, usually GNU-obsessed, would miss that out.

      GNU Radio is a pretty amazing piece of software. I attended a talk about it at Linux '05, and was amazed by the capabilities. When they say they are decoding HDTV, they mean that they are doing it in software. All of it. Not just decoding the MPEG-2 streams, but everything this side of the analogue to digital convertor. They are not running it through a decoder box and grabbing it from a FireWire connection, they are capturing the radio signals, converting them into digital signals in hardware and then doing everything else in software.

      The basic architecture of GNU Radio is a filter API. Individual filters are written in C++ for performance and then they can be joined together and controlled with Python, making the barrier to entry very low for anyone who wants to tinker with it. Don't be fooled into thinking you need an expensive receiver like the one in TFA to play with it either, it will accept input from a large number of ADCs, including sound cards. You can use it to apply transformations to any digital waveforms.

      You can use it to implement something like 802.11 entirely in software, generate telephone dialling tones on your sound card, modulate your voice to sound like a Dalek, decode HDTV signals, or a huge range of other things. It turns your PC into a hugely powerful programmable DSP.

      The hardware in TFA is just icing on the cake. As I recall, the specs for a slightly simpler model are available from the GNU Radio site, so you can build one yourself if you have (a lot) more time than money.

    • Ok, I must be missing here (the details of HDTV were not very specific). Do other people NOT decode HDTV, and is that milestone? Any product by DVICO will also decode HDTV. My Dvico USB unit decodes it.

      The milestone is that it's done entirely with open-source software, instead of a proprietary chip.

    • Re:decoding HDTV? (Score:3, Informative)

      by maxume (22995)
      The novelty of GNU Radio is that instead of just the HDTV decoder being software, the tuner is too. If the application(TV, fm radio, HDTV, etc) you want falls inside the frequency range your hardware can sample, you can build a software tuner. The novelty of this hardware is that the cheapest prior solution started in the several of thousands -- generalized a/d converters intended for scientific data sampling, like: http://www.atmel.com/dyn/products/devices.asp?fami ly_id=611 [atmel.com]
  • I hear hype... (Score:2, Informative)

    by SuperBanana (662181)
    "Here," he explains, "I'm grabbing FM." "All of it?" I ask. "All of it," he says. I'm suddenly glad the soundcard isn't working.

    Not quite- in order to fit the swath of FM radio into that USB2 pipe, it isn't sampling it in any great detail. If you tried to decode one station, it'd most likely sound like a tin can, unless you sampled a narrower slice of the FM band. So don't get too excited. Claiming the motherboard or these devices are "universal" is extremely misleading. You buy modules that transmi

    • Re:I hear hype... (Score:4, Interesting)

      by David Bengtson (87963) on Monday June 05, 2006 @05:59PM (#15475808)
      Sorry, GPS location requirements don't rely on the timing on the board, all of the timing and position is derived from the received signal. You need to be able to receive 3 or more satellites for a fix. There are several folks working on GPS receive applications for the USRP right now.

      Dave
      • Sorry, GPS location requirements don't rely on the timing on the board, all of the timing and position is derived from the received signal. You need to be able to receive 3 or more satellites for a fix

        I don't think you understand how GPS works. Simplifying- a GPS receiver looks at when signals with the same timestamp arrive, and deduces how far it is from each satellite from that. If a signal from Satellite A saying "hey, it's 12:01:05 right NOW arrives a second after a similar signal from Satellite B,

        • by Anonymous Coward
          I don't think you understand how GPS works. Simplifying- a GPS receiver looks at when signals with the same timestamp arrive, and deduces how far it is from each satellite from that. If a signal from Satellite A saying "hey, it's 12:01:05 right NOW arrives a second after a similar signal from Satellite B, then the receiever knows that it is 1 light-second further away from Satellite A than B (this is a gross exaggeration of the scale of time involved.) With 3-4 satellites, you get a position fix.

          You are
        • Both require -staggering- accuracy that a PC, or your USRP board, are incapable of providing. Clock skew considered perfectly acceptable in a PC is considered monumentally inaccurate in a GPS receiver...and the timing resolution isn't anywhere near good enough either. You're talking about comparing timing in LIGHT FEET, and light takes 1/299,792,458th of a second to travel a meter. It's about one NANOSECOND a foot, so you need resolution exceeding 10nS.

          You've got to do a lot of signal processing to ignore

        • by David Bengtson (87963) on Monday June 05, 2006 @10:09PM (#15477162)
          Sorry, I know exactly how GPS works, I'm working on a GPS receiver board for Gnu Radio (www.keystoneradio.com).

          You don't need absolute timestamps on each sample to get distance. The timing is encoded in the PN sequence in the transmission from each satellite. Also included in the transmission from each satellite is the satellite orbit information and the exact time that the GPS system uses. First, you receive 1 satellite, and then set your GPS clock to the system clock. Once your handheld GPS is set to the system clock, you can figure out how far you are away from the satellite by determining time of flight from the satellite to the handheld (You know the PN sequence, and you know the time. You can figure out the time that you received the signal, and then you can determine the distance)

          Once you know the distance from 3 satellites, then you know you are in 1 of 2 locations. If you further assume that you are reasonably close to the earth's surface, then you knock off one of the possible locations. More satellites will give you a better estimation by giving you more position estimates to average out.

          As far as the signal processing, the GPS signal comes in to the antenna pretty close to the thermal noise floor, and so it's a bit tough to receive. Because it's a direct sequence spread spectrum system, you get 43 dB of processing gain from the de-correllators which helps significantly. Multi-path isn't really to much of an issue because the signal is primarly from overhead. Absorbtion is more of an issue, and is something that Garmin/SiFR etc spend a lot of time dealing with.

          As far as beating the current state of the art in GPS receive algorith's with a half dozen guys working in their basement, probably not. As an educational thing, it's pretty useful.

          Dave
          • You can take multiple measurements and use the Doppler shift.

            One measurement of the carrier frequency locates you on a cone whose axis is along the direction of satellite's travel.

            A second measurement should locate you on a curve which I believe to be a hyperbola. (the axis of travel has changed)

            A third measurement locates you on a point.

            If you can pick up quasars, the Earth's rotation should eliminate any need for satellites.
        • I was a software engineer on a GPS project for aircraft about 10+ years ago. After an RF front end, the signal was brought into a DSP and slow (by modern standards) processor combination. The software wasn't rocket science and the signal recovery just used the special coding embedded in the GPS signal for recovery.
    • Re:I hear hype... (Score:5, Informative)

      by lowen (10529) on Monday June 05, 2006 @06:35PM (#15476099)
      I have two of these personally. At PARI we have four of them. They work. And work well, for radio astronomy.

      As to capturing the entire FM band at one fell swoop, I know for a fact that the USRP and a good USB 2.0 High-Speed host can sustain 32MB/s transfers. This becomes an actual sampling rate of 8MS/s in quadrature, which means a full 8MHz band can be sampled at 12 bit precision. The FM band is 107.9-87.9=10MHz wide. At 12 bits, no, you can't get the whole band in. However, the USRP can go 16MS/s at 8 bits (again, in quadrature, which effectively doubles the sample rate), and consume 32MB/s across the USB. Since FM (frequency modulation) doesn't require large dynamic range in terms of bit depth, it is possible that you could get nearly full fidelity audio out of all FM channels simultaneously: but you would need one big honking PC to demodulate in real-time.

      As I am a licensed Amateur, I can use this as a transmitter, in the bands and with the modulations to which my license class is allowed. I have the 400-500MHz transciever board; I am of course limited to the 70cm Ham band for transmission, and I of course honor that. It works quite well.

      For radio astronomy, I have the DBS_RX board, and it directly tunes several radio astronomy bands, including the Hydrogen line at 1.42GHz. It works quite well for both continuum and spectrum studies, although I still have some bugs (with considerable help for the GNUradio project and other programmers) to work out.
    • Re:I hear hype... (Score:5, Informative)

      by lenhap (717304) on Monday June 05, 2006 @06:50PM (#15476215)
      You obviously read the article, but did you think to read any details on the actual device? The baseboard/motherboard has a ADC that can capture 10 million samples per second at 12 bits per sample. So doing simple math and ignoring protocol overhead to transmit all 10 million samples would require 12bits per smaple * 10 million samples per second = 120 million bits per second. USB2 has theoretical bandwidth of 480 million bits per second, so the rough back of the envelope calculations would suggest that the full 10 million samples the ADC can capture could be transmitted to the computer over USB2.

      So if we assume that the all of the data can get to the computer, could the device grab all of the FM in such a format that it could be "decoded" into normal FM quality audio? Short answer, yes. The daughter cards for the baseboard/motherboard convert the signal down to an IF (intermediate frequency) within the range of the ADC. If you really want to know how IF and all that stuff works, look up FM radio on wikipedia.

      What really annoys me is how you try (key word is "try") to explain that this device cannot do GPS. You do NOT need accurate timing to do GPS. Time is part of the GPS solution, so you only need a simple realitively accurate clock. The $100 handheld GPS units don't have anything more accurate than the clock in your pc, which this device would have access to (the clock in your pc, that is). In fact GPS is often used to provide timing for applications like NTP servers. Again you would need one of the daughter cards to convert the GPS signals down to an IF. The actual GPS signal (C/A-Code) is transmitted in the L1 band (1575.42 MHz) which when converted down to an IF could be handled by the ADC in the device. From there you would only need to aquire 4 satelites to get a simple PVT solution (position, velocity, and time). And, FYI, GPS in certain applications and situations can give accuracy to within cm range (mm range if using differential GPS and post processing which this device could do).

      So before posting as if you are an expert, look up some stuff on what you are writing...or at least explain that you aren't positive on how everything works but you don't think it could do what it claims. And yes, I actually work doing military GPS for a company and have a BS in EE with a concentration in communications (so I should hopefully know what I am talking about).
    • No, GPS is designed such that no precision timming is needed inside the reciever. The precisionclocks live inside the spacecraft. The spacecraft trans mit digital messages containing only the orbital parameters and the time of day. Recivers only have to look at the low data rate digital messages and compare the time field in each. The reciever then solves a set of equaations and gets location. Solving can take a good deal of time on a low end device so the GPS really tells you where you were a second
  • by ps_inkling (525251) on Monday June 05, 2006 @06:14PM (#15475926)
    The ICOM PCR1500 [universal-radio.com] (Japanese [icom.co.jp]) already receives everything from DC to 1.3GHz (minus analog cell frequencies, unless you're a government user). No additional modules required, and uses USB and fairly open software controls.

    Or, for even cheaper ($350), Ten-Tec's RX-320D [tentec.com], with digital radio. Everything from DC to 30MHz (shortwave).

    I've never used any of them, your milage may vary, etc.

  • by Erandir (578490) on Monday June 05, 2006 @06:29PM (#15476049)
    Be careful of that seemingly innocuous qualification: "with the right software and daughterboards"... both imply serious limitations to the technology.

    Firstly, the "right" software: Even with a reasonably fast processor (say 3 GHz) today, you are typically only be able to process, at most, a few million samples per second -- especially if you are performing complicated modulation/demodulation, coding/decoding, filtering and protocol processing. Each sample may require substantial computation, and that limits the number of samples you can process per second. That, in its turn, affects the bandwidth that a processor can address (i.e. how wide a part of the radio spectrum you can "see" at any one time).

    Secondly, the "right" daughterboards: To be able to address a wide bandwidth, we require digital-to-analog and analog-to-digital converters with high sampling rates. These are limited by the state of the art in signal conversion technology -- typically a couple of million samples per second if we want a reasonable number of bits per sample (at a reasonable price). Push it beyond that, and we have to be happy with fewer bits per sample (may 10 or 8 bits). This introduces noisiness to the signals being transmitted or received, degrading the fidelity of the software-defined radio.

    Also, a daugterboard usually has some form of signal translation hardware ("mixers") to translate the low-frequency signals that computers can generate to and from the higher parts of the radio spectrum. Although broadband mixers are available, they need tunable oscillators (reference frequencies), and these tend to be limited to narrower parts of the spectrum. Also, analogue filters, amplifiers and antennas (which all form part of a typical software radio front-end), usually are limited to specific ranges of the radio spectrum.

    In short, software radio daughterboards tend to be fairly application-specific (or at least spectrum-specific). We can do a lot of things in software, but a "universal" software radio needs a lot of hardware swapping. I think that makes it a bit less "universal". It might also push the cost of a truly multi-purpose system quite a bit beyond $550.

    But I'm glad to see this technology receiving such mainstream attention, and I applaud the efforts of the designers. I just think that TFA (and the post) could maybe be a bit less sensasionalist.

    And yes, IAASDRE.

    G-J

    • The Right Software: The GNUradio stack.
      The Right Duaghterboards: The USRP is outfitted with two Analog Devices AS9862 MxFE chips, each possessing two 64MS/s 12 bit ADC's, two 128MS/s 14 bit DAC's, and assorted auxiliary ADC's and DAC's for things like AGC.

      The daughterboards themselves are just RF frontends. The DBS_RX, for instance, uses a Maxim satellite receiver chip that quadrature downconverts from the RF directly to plus and minus baseband. One MxFE can do quadrature, and is a good match to the sing
    • The parent poster writes: Be careful of that seemingly innocuous qualification: "with the right software and daughterboards"... both imply serious limitations to the technology....Even with a reasonably fast processor (say 3 GHz) today, you are typically only be able to process, at most, a few million samples per second -- especially if you are performing complicated modulation/demodulation, coding/decoding, filtering and protocol processing. Each sample may require substantial computation, and that limits
  • WinRadio (Score:3, Interesting)

    by femto (459605) on Monday June 05, 2006 @06:35PM (#15476094) Homepage
    Surely these guys should give acknowledgement to WinRadio [winradio.com]? I first played with one of these around 1995. That particular model was a PCI card able to receive from close to DC through to 3GHz.
    • How well do these cards handle noise from the computer? For quite some time now, I've wanted to put a handful of cards into a machine and set up a 'scanner' that would log everything to MP3 files. My concern is that every computer I've ever owned has spewed noise over various portions of the spectrum; I can only imagine what would happen if I put it inside a computer. Or are the cards really well-shielded somehow? (And for that matter, are they worth the money? I seem to recall them being very expensive.)
      • How well do these cards handle noise from the computer? And for that matter, are they worth the money? I seem to recall them being very expensive.

        WinRadio is available as internal PCI and external USB devices. Prices start at $500 US for general-coverage shortwave. Winradio Receivers [grove-ent.com]

    • Winradio seems to have a max IF of 15kHz. Far, far too small to do anything with TV, much less GPS and other fun things. Perhaps there are models I didn't see (very brief visit).

      Software defined radio is nothing new. What's new is that there are more hands in the pot - more people trying to do cheaper generalized stuff with it, as opposed to bog standard radio (voice, CW, etc) communication, and putting the hardware together in such a state that software developers can hack at it without any electroni
    • No ... the original WR1000 was largely an analog radio. That's not SDR. The real novelty of the original WinRadio models was computer control - tune to a particular frequency - check received signal strength - select mode like AM vs. FM or SSB. You could write software to do automated sweeps of spectrum and log the results but the actual signal path was mostly analog.

      One more thing - the PC internal version was an ISA card - NOT PCI.

      WinRadio finally introduced a PCI version about a month ago (not ten years
  • by AB3A (192265) on Monday June 05, 2006 @06:40PM (#15476137) Homepage Journal
    This is a huge step forward for computer assisted modulation techniques and wide band scanning. However, I should point out one very important limitation: Dynamic Range.

    For those of you who are too lazy, read this [radio-electronics.com].

    Now let me point out that while the A/D converter is fast, it only has 12 bits. This will give you about 72 dB of dynamic range. Modern reciever design can yeild dynamic ranges of 100 dB or better (depending on how you measure it). Some day we'll get this performace from 16 bit A/D converters. When that happens, expect the designs of radio to change to software over hardware.

    This is the trade off for building a reciever of this sort. There is no free lunch folks...
  • by DrBuzzo (913503)
    This unit isn't actually that new. I've been looking into software defined radios for a while. They offer a real lot of flexability and power in areas where other hardware is lacking.

    With the transition to digital communications, it's becoming harder for the scanner/receiver hobbiest to surf the airwaves. While low-speed signals can often be decoded through a sound card, more wideband communications need another solution. Generally, this means special hardware for each type of signal. Weather sa
  • With prices starting at just $550 this new toy is accessible by most anyone.

    So the PS3, which is an actual toy mind you, is "prohibitively expensive", while an esoteric piece of hardware only 1 in 10 people would even know how to use is "fun for the whole family, go out and buy one at Walmart"?
  • The final puzzle piece in in place. Run this software on the CELL processor and have a radio that can receive and decode anything. Oh wait, that means a $5 radio will now be $300, oh well...

    Seriously though, this is an awesome idea, its like the internet 20 years ago, or the personal computer 50 years ago. 100 years from everything will be the same exact microscopic chip running specialized software, from trans dimensional warp drives to an automated bionic eyelash.

Bringing computers into the home won't change either one, but may revitalize the corner saloon.

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