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Hitachi's Tiny RFID Chips

Posted by kdawson on from the bugged-dust dept.

paltemalte writes "Hitachi has just come out with a new crop of RFID tags, measuring only 1/20 of a millimeter square. That's 1/8 the size (in linear dimension) of Hitachi's currently shipping mu-chips, which are 0.4 mm square. The new chip's width is slightly smaller than a human hair. These chips could put an end to shoplifting forever, but they could also be used by a governments or other entities to 'dust' crowds or areas, easily tagging anyone present without their knowledge or consent. Will someone come up with a surefire way of neutralizing chips that may be on your body or in your clothing?" Hard to pin down a source on this. The article cites another blog, which points to an article in Japanese.

10 of 153 comments (clear)

  1. What they didn't tell you by JesseL · · Score: 5, Informative

    Most RFID chips still have to be attached to a much larger coil antenna to make a tag that will actually work.

    --
    "Prefiero morir de pie que vivir siempre arrodillado!"
    1. Re:What they didn't tell you by sysopd · · Score: 2, Informative

      Most RFID chips still have to be attached to a much larger coil antenna to make a tag that will actually work.

      The "new" RFID innovation for embedding in clothing etc is conductive thread antennae. The antenna is woven into the clothing or item and disguises as an ordinary thread. To be less conspicuous the thread can be woven into the label or a seam.

      Philips patent for a flexible fabric antenna.

  2. Small tags have inherent limitations by Anonymous Coward · · Score: 5, Informative

    These tags are 1/20th mm square, correct? This means they are 1e-3/20 m = 5e-5m across. This corresponds to a frequency of 6 THz or for a quarter-wave antenna something like 6/4 THz = 1.5 THz. This is a very high frequency and not the easiest to make with existing technology (especially at significant power levels). This means that querying tags of this size is probably only feasible at short range using a beam that is directed at the tag as opposed to just looking in a vague region of space. Other companies have made optically addressed tags that push this direction even further but with even worse limitations. Also, at ~1 THz the attenuation due to dielectrics (or especially water) is very high and this limits the distance over which one can practically probe the chip.

    1. Re:Small tags have inherent limitations by Kadin2048 · · Score: 3, Informative

      This is just the transciever chip; it has to have an external antenna. Elsewhere, people have discussed their current chip offerings, which have antennas in the ~50mm range. Generally they print them out in the shape of a labyrinth-like square, to take up less space, but it still increases the size pretty dramatically.

      I suspect if you took the same antenna and made it into a 3d cube instead of a 2d concentric spiral, you'd probably end up with something pretty small ... still, not "dust" size.

      --
      "Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
  3. Re:Something to worry about... but maybe not so mu by sunwukong · · Score: 3, Informative

    Hitachi's current product, the Mu-chip, has a supposed reading range of 400mm with a 54mm antenna.

    Dunno what the proposed range and antenna requirements for the new chip will be.

  4. EASY to pin down a source. by 1u3hr · · Score: 2, Informative
    The summary says: "Hard to pin down a source on this. The article cites another blog, which points to an article in Japanese."

    RTFA FFS. It has a link to Hitachi, in English:

    The mu-chip is Hitachi's response to resolving some of the issues associated with conventional RFID technology. The mu-hip uses the frequency of 2.45GHz. It has a 128-bit ROM for storing the ID with no write-read and no anti-collision capabilities. Its unique ID numbers can be used to individually identify trillions of trillions of objects with no duplication. Moreover with a size of 0.4mm square, the mu-chip is small enough to be attached to a variety of minute objects including embedding in paper.
  5. Re:Something to worry about... but maybe not so mu by Djupblue · · Score: 3, Informative

    The reading distance is not so much limited by reader sensitivity as the amount of rf-power received by the chip. The chip has to receive enough power to operate, albeit very little. Then the chip creates a modulated reflection, that means that the more power you transmit the more power you get back. The specified reading range is not a hard limit, you can get a lot longer distance if you use a reader that put out more power than the spec states. We read rfid chips at up to about 10 meters in optimal conditions with compliant readers.

  6. Re:Covered with Hair? by paltemalte · · Score: 2, Informative

    Again the slashdot editor obfuscated my post. I wrote 'the WIDTH of the RFID chip is less than the WIDTH of a human hair'. RTFA and see the images for yourself. They could easily be 'dusted' out.

    --
    Sam has one liberty, which he sacrifices for one security. Can you tell me what Sam has now?
  7. Re:Something to worry about... but maybe not so mu by kirun · · Score: 2, Informative

    Why would they bother RFIDing the crowd when they could just spray them with Smart Water? The patrols with their hi-tech scanners could be replaced with ones wielding UV lamps.

    --
    I'm scared of numbers that can't be written as a fraction. It's an irrational fear.
  8. Re:Fighting back with RFID readers by Richy_T · · Score: 2, Informative

    No longer affiliated with this place but they have an affordable kit and are helpful with questions intersoft-us