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Universal Radio Grabber: the USRP

Posted by ryuzaki0 on 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."

13 of 189 comments (clear)

  1. The real question by Umbral+Blot · · Score: 5, Insightful

    The real question: how long before it becomes illegal to own or use one?

    --

    Philosophy.
    1. Re:The real question by Intron · · Score: 2, Insightful

      it has frustrated me that they want to transmit "in the clear"

      Where "they" means the NSA, in this case.

      --
      Intron: the portion of DNA which expresses nothing useful.
    2. Re:The real question by egomaniac · · Score: 5, Insightful

      It makes much less sense to license receivers. The radiation is there, passing through people, even. Frankly, I don't understand why anyone would think that I don't have the right to intercept any signal which passes through my personal space and process it however i please.

      So it should be legal for me to use a night-vision scope to look into my neighbor's bedroom window at night? After all, her naked body is reflecting electromagnetic radiation into my personal space. Amplifying it into a visible image, digitizing it, and making it available on the Internet seems like a perfectly logical step, doesn't it?

      People have an expectation of privacy. They expect you won't be sneaking around peering into their windows at night, and they expect you won't be intercepting and decoding their personal telephone calls. Yes, you have the right to decode electromagnetic radiation. And yes, the callers have a right to privacy. Any time two different rights conflict, one or the other has to take precedence. Privacy is a much more desirable-to-society right than is the ability to spy on our neighbors, and so privacy wins.

      --
      ZFS: because love is never having to say fsck
    3. Re:The real question by makomk · · Score: 2, Insightful

      So it should be legal for me to use a night-vision scope to look into my neighbor's bedroom window at night? After all, her naked body is reflecting electromagnetic radiation into my personal space. Amplifying it into a visible image, digitizing it, and making it available on the Internet seems like a perfectly logical step, doesn't it?

      So I take it you think that we should ban all night vision scopes, then? Because that's effectively what's been done...

    4. Re:The real question by TheGratefulNet · · Score: 4, Insightful

      People have an expectation of privacy

      in the US?

      in the MODERN US?

      (have you not been reading the news at all, over the last say, year or two?)

      --

      --
      "It is now safe to switch off your computer."
    5. Re:The real question by tacarat · · Score: 3, Insightful

      So it should be legal for me to use a night-vision scope to look into my neighbor's bedroom window at night? After all, her naked body is reflecting electromagnetic radiation into my personal space. Amplifying it into a visible image, digitizing it, and making it available on the Internet seems like a perfectly logical step, doesn't it?

      Ummm. Radio transmitters are much more along the lines of your neighbor changing or whatever in the middle of a crowded public area with people that could turn around and watch at any point. Your example, peeking into her window, is more deliberate. For one thing, it's targeted. You knew specifically who you wanted to observe. Another is that she made an attempt to protect her privacy by going inside. In this example, you've taken steps to circumvent this by searching for and exploiting an opening (earn your white hat and let her know her curtains are open).

      Personally, I'm waiting for the day when SETI gets sued (or disintegrated) for intercepting alien phone calls. I'm betting the first decoded message is for 1-900-UFO-HOTY

      --
      "Common sense will be the death of us all"
  2. Ouch $550 by 9mm+Censor · · Score: 4, Insightful

    I would hardly call _starting at_ $550 accessable to almost anyone.

  3. Re:P2P Telephone? by CRCulver · · Score: 2, Insightful

    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.

  4. Re:P2P Telephone? by Anonymous Coward · · Score: 1, Insightful

    Because broadcasting your conversation is much more secure?

    Or maybe because warrants aren't required to listen in on wireless conversations so there's no controversy?

  5. Re:P2P Telephone? by misleb · · Score: 2, Insightful

    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

    --
    "THERE IS NO JUSTICE, THERE IS ONLY ME." -Death
  6. What this is and what this isn't by AB3A · · Score: 4, Insightful

    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.

    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...

    --
    Nearly fifty percent of all graduates come from the bottom half of the class!
  7. Re:"the right daughterboards" by lowen · · Score: 2, Insightful

    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 single RF input I/Q output DBS_RX board to 900-2400MHz receive.

    The USRP gets this 64MS/s bitstream munged down to a manageable size by use of an Altera Cyclone FPGA, which, using CIC and half-band filters implemented with CORDIC, bitmashes things down to a rate that will fit over the USB 2.0 High-speed interface.

  8. Comment removed by account_deleted · · Score: 2, Insightful

    Comment removed based on user account deletion