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Networking Wireless Networking Technology

Turning Your Home Wiring Into a Giant Antenna 135

An anonymous reader writes with this IBT snippet: "Imagine if you could run a wireless sensor device for years without ever having to replace the battery. Turns out, the idea of a battery-less wireless device might not be too far off. Researchers at the University of Washington and the Georgia Institute of Technology developed a small node sized device that uses the residential wiring from a building or home and transmits information to and from almost anywhere else from within. The device is called Sensor Nodes Utilizing Powerline Infrastructure, or SNUPI. It uses basic copper wiring as a giant antenna to receive wireless signals at a set frequency. When the device is within 10 to 15 feet of electrical wiring, it uses the antenna to send data to a single base station." (For "node-sized," think "size of a breakfast cereal prize.")
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Turning Your Home Wiring Into a Giant Antenna

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  • Just run a wire out back to the railroad line and attack to a rail.

    • Re: (Score:3, Funny)

      by Anonymous Coward

      "Attack", "rail". Expect a visit from a not-so-friendly representative of Homeland Security.

      Your Best Friend and Big Brother,
      The US Government

    • Re: (Score:3, Funny)

      by suso ( 153703 ) *

      Yeah, negotiating right of way with the railroad company. Brilliant! Why didn't I think of that?

    • Re: (Score:2, Funny)

      by Anonymous Coward
      You should probably re-evaluate how you approach your rails, attacking them shouldn't be necessary!
    • They will not be very happy when you mess up the track circuits.
    • Re: (Score:3, Funny)

      by fewnorms ( 630720 )
      Be happy they didn't call this 'Sensor Nodes Utilizing Conductive Infrastructure' ... the short version of that would not be pretty. Come to think of it, the short version IS not that pretty :)
    • by mcgrew ( 92797 ) *

      It sounds good in theory, but in practice it won't work at all. I lived very close to the railroad track when my kids were little, and you could always tell when a train would show up fifteen minutes before you could hear it, because the train messed up the TV or radio signal.

      Besides that, antennas laying on the ground don't work very well.

      And on top of that, you tune an antenna to the frequency you want to send or recieve by its length. A microwave needs a short antenna, not one that's hundreds of miles lo

    • Attack a rail? Kind of sounds like a modernization of Don Quixote.
  • Interesting (Score:2, Interesting)

    by iONiUM ( 530420 )

    This is actually a pretty cool idea. It means in any populous area you wouldn't need wireless hubs or cell towers anymore, just the whole city would be humming.

    Of course, if there is indeed any higher risk of cancer from radio waves, well... I pity everyone who lives there :)

    • Re: (Score:1, Interesting)

      by Anonymous Coward

      "Of course, if there is indeed any higher risk of cancer from radio waves, well... I pity everyone who lives there :)"

      Radio waves are already being generated by the wiring, albeit at much lower frequencies (e.g., 60Hz).

    • by mcgrew ( 92797 ) *

      These are ultra-low power transmitters that use induction to power themselves and send a signal back to a central node that's powered the traditional way, by plugging it in. The signal only goes ten or fifteen feet, so your idea wouldn't fly.

    • >>>This is actually a pretty cool idea

      No not really. I got a device like this for my TV. Plug it into the wall socket and it "turns your whole house into an antenna". It worked worse than an ordinary settop rabbit ears/loop antenna. I have my doubts this Sensor Node would work any better.

      • by nomel ( 244635 )
        That's because the wavelength of TV transmissions is around 2 feet...an antenna with elements longer than this can't efficiently capture the radio energy! The goal of antenna is to induce a resonance in the elements. This is why most antennas you see are some nice fraction of the wavelength; the peak of the radio signal helps reinforce the wave already moving in the antenna. This has the effect of having a nice change in impedance between the air and the antenna for the incoming wave. The closer the impedan
        • Yeah good. But you failed to explain why this Sensor Node would work any better? I still don't think it would.

          Also the ideal antenna would not be a fraction of the wavelength, but exactly the wavelength. So if you want VHF 6 from Philadelphia's WPVI-TV, then 114" (9 1/2 feet) would be the ideal size for your receiving antenna.

          • by nomel ( 244635 )

            You're right, I didn't. I was shedding light on why your whole house antenna was worse that your bunny ears.

            I didn't say ideal antenna would be a fraction, I said "This is why most antennas you see". Like you said, they get unwieldy for longer wavelengths. More importantly, at full wavelength, the antenna pattern becomes mostly useless. With shorter wavelengths, you get more of a smashed donut, meaning nice gain in the horizontal direction, less from up and down. At full wavelength, you get a null in the ho

  • Oldhat (Score:3, Insightful)

    by symes ( 835608 ) on Thursday September 16, 2010 @01:47PM (#33602010) Journal
    here [wikipedia.org] is one someone knocked up a 120 years ago.
    • by Mashiki ( 184564 )

      Not only that, but IBM used this idea for several years with their 'home automation services' to control things from your PC.

    • When I was 11 I got a Heathkit Crystal set kit for my birthday, it came with a variable capacitor a diode a small Bakelite knob a phenolic tube a spool of enameled magnet wire a square of plywood, solder, screws, a little piece of sandpaper a pair of fanstock clips with a monophone headset. I had to buy a soldering iron. Let me tell you I was thrilled, and I even entered it into the science fair.

      • by symes ( 835608 )
        Neat - I wasn't lucky enough to get a crystal set but did get various other kits. I knocked up a two-way radio with a mate once. I feel sorry for youngsters these days, they just get iPods. Perhaps Jobs should think of an iCrystal kit.
      • I had a crystal radio kit as a kid, too. I don't remember if it was a Heathkit or not (although I remember my dad building several Heathkit projects), but it was still a very cool project. I do remember being disappointed it wasn't louder, though, lol.

        Now that you've stirred up the memories, I want to build another crystal radio :)
    • From the summary:

      Imagine if you could run a wireless sensor device for years without ever having to replace the battery. ... a small node sized device that uses the residential wiring from a building or home ...

      So, if we're already surrounded by a dedicated hard-wired power delivery infrastructure, we don't need batteries if we use this thing.

      Or you could just plug the damn thing in.

  • by Nursie ( 632944 ) on Thursday September 16, 2010 @01:48PM (#33602024)

    They already get upset enough about HomePlug style ethernet-over-power devices.

    • by mike449 ( 238450 ) on Thursday September 16, 2010 @02:17PM (#33602390)

      This new "node-sized" device consumes 1mW when transmitting and the home wiring is used as a receiving antenna. If HomePlug radiated this much, ham guys would be really happy.

      • This new "node-sized" device consumes 1mW when transmitting and the home wiring is used as a receiving antenna.

        So it's not, as the summary implies, two-way communication?

        If not, that's a letdown. Milliwatt wireless commo would be amazing for device battery life.

    • Re: (Score:3, Interesting)

      by Oloryn ( 3236 )
      With the power levels being used, interference to ham operation isn't likely to be a problem. What's likely to be more of a problem is - how RFI-susceptible are the receivers going to be? They appear to be targeting the upper short-wave and lower VHF region (10-40Mhz). These receivers need to be pretty sensitive to pick up the low-level signals being sent by the sensors. If a neighbor (or the occupant) fires up a legal-limit ham transmitter (or a CB with an illegal amplifier), will they be selective eno
  • Smart money says that SNUPI is a backronym because they wanted the name to be catchy.
  • by interval1066 ( 668936 ) on Thursday September 16, 2010 @01:56PM (#33602128) Homepage Journal
    IF this is widely adopted, place your bets on how long it takes for snoopers and sniffer to start stealing your sensitive data. I'm guessing a scant week after a city touts a complete success at a city-wide installation a report will come out on how a scammer scams that town out of kajillions.
  • by scheme ( 19778 ) on Thursday September 16, 2010 @01:56PM (#33602138)

    Patel said. "Most systems are designed thinking the battery will last less than a year. Now the device sold can have the battery integrated and frenetically sealed. "

    I'd like to see one of those frenetically sealed batteries. Or maybe just see a video of the battery being sealed.

  • I have tried internet over power lines and it never worked for me.
  • FTA: These devices are for "communicating back to the bay station." Think the author knows anything about wireless?
    • Another bit of brilliance:

      With SNUPI, Patel and his team found a way to distribute the wireless sensors in a more practical way. Whereas the traditional method uses 99 percent radio waves, the SNUPI method uses less than one percent

      WTF? What the holy hell does that even mean? And other unanswered questions: what on earth is this useful for? What kind of sensors do they intend to attach to this, and what is intended to be done with the data gathered? And: "a node-sized" device? Ok, so how big is a node?


    • FTA: These devices are for "communicating back to the bay station." Think the author knows anything about wireless?

      All he's saying is that the things only work near large bodies of water.

  • by Anonymous Coward on Thursday September 16, 2010 @02:02PM (#33602222)

    These powerline 'type' technologies are like just bad bad news for Hams and shortwave enthusiasts as it wipes out the bands, unless notch filters are employed, which I doubt it.

    • by MBCook ( 132727 )

      Well one of the problems with powerlines is that you need high power to get the signal the distances you want, the lines are lossy because they weren't designed for the frequencies, and the fact they are just long pieces of wire makes them ideal antennas.

      If you're only broadcasting to your house, the power could be a lot lower. The fact that the "antennas" are smaller, turn more, and inside walls would help some too.

  • seems an old idea... (Score:2, Interesting)

    by dslmodem ( 733085 )
    I have been working in a DSL company a few years back. For DSL systems, the AM signals could be an issue since they can couple into the long twist pair lines and then, be fed into receiver. So far, I got the idea to utilize the long wires (phone lines, power line, etc) to perform short range radio communications or sensors with other devices. Problems? Many. Overall, it is very hard to control, i.e. taking a lot of noise/interference and emitting a lot of energy (could affect other devices).
  • (For "node-sized," think "size of a breakfast cereal prize.")

    Don't know about yours, my node is way bigger than this.

    • First we were measuring things in Library-of-Congresses, now we measure them by Breakfast-Cereal-Prizes?

      Geek1: How big is that new hard drive of yours?
      Geek2: huge, at least 1,000 Library-of-Congresses. How big is your new laptop?
      Geek1: it's small, about the size of 5 Breakfast-Cereal-Prizes. Got the new iPhone-a-Droid too, it's a little bigger than a Breakfast-Cereal-Prize.
  • What a great idea. The whole building as a huge super-conductive antenna designed and built expressly for the purpose of pulling in and concentrating spiritual turbulence. Your girlfriend, Pete, lives in the corner penthouse of Spook Central.

    Mark my words! Do this, and many Shuvs and Zuuls will know what it is to be roasted in the depths of the Slor that day, I can tell you!

  • EMC... (Score:2, Insightful)

    How can this ever be approved? I imagine this can cause all sorts of problems. The power grid in a normal house is not designed for this, same thing goes for the ethernet over power crap. There are all sorts or regulations about keeping net pollution down, and using it as a transmission medium goes directly against this.
  • Units (Score:5, Insightful)

    by Locke2005 ( 849178 ) on Thursday September 16, 2010 @02:33PM (#33602570)
    For "node-sized," think "size of a breakfast cereal prize."?

    For those of us that haven't eaten cereal that comes with prizes for at least 40 years now, can you express that in more traditional units, e.g. volkswagens, libraries of congress, or common US coins? Alternatively, you you just give the fucking dimensions.
    • Re:Units (Score:5, Informative)

      by dtmos ( 447842 ) * on Thursday September 16, 2010 @02:51PM (#33602834)

      It's 3.8 cm by 3.8 cm by 1.4 cm [washington.edu] (second page, first column, second paragraph).

    • If "node-sized" was the only part of the summary you found unclear, I commend you.
    • by Inda ( 580031 )
      It's called a prize? Amazing.

      "Well done, you've worked out how to open the box, now have a prize!"
    • by ediron2 ( 246908 ) *

      > For those of us that haven't eaten cereal that comes with
      > prizes for at least 40 years now, can you express that in
      > more traditional units, e.g. volkswagens, libraries of
      > congress, or common US coins? Alternatively, you you just
      > give the fucking dimensions.

      1 - I still buy *THAT KIND* of cereal, you insensitive clod! Also, Crackerjack. You should, too. Live a little.
      2 - The whole analogy is busted -- I never see prizes anymore. FWIW, Crackerjack prizes suck the wax tadpole, too. That

      • 2 - The whole analogy is busted -- I never see prizes anymore. FWIW, Crackerjack prizes suck the wax tadpole, too. That's the cardinal flaw with this description: there are probably young /.'ers that have never seen a toy in/from a cereal box, and not because their mom was one of those twisted no-corn-sugar holistic diet types.

        Note, I *AGREE* with you, generally. However, prizes still show up in cereal sometimes. I know I have a couple of hacky sacks from Frosted Flakes from within the past few years. Mo

    • Yeah... like saying: Oh, you don't know what a blivet is? Its pretty much the same as a poiuyt.

      Fucking thanks for clearing that up.
  • Sounds like they are using the frequencies reserved in the US for R/C control, which require no license. Also, since they are using the power lines as a receiver, not a transmitter, HAM enthusiasts shouldn't have a problem with it. For the very limited niche it is designed for (home data collection), it's a cool system.
  • For "node-sized," think "size of a breakfast cereal prize."

    Is that a European or African cereal prize?

  • In the UW paper, there was no detailed description of the powerline inside the test home. What was the wiring? I'm guessing it was NM cable (a.k.a. "Romex"), or wire in nonmetallic conduit. If a home is wired with wire in metal conduit or armored cable (f.k.a."BX"), the grounded metal enclosure probably has an adverse effect on performance of the SNUPI system.
    • Who the hell runs BX or MT inside a house? NM 14-2 is all over the damn place.

      • Re: (Score:2, Insightful)

        by e9th ( 652576 )
        My house was built in 1957. All interior wiring is in EMT or IMC (plus a little Greenfield to the fixed appliances) or within steel conduit bodies and device boxes. Not an inch of NM.
        • And this is inside the walls?

          I guess I've been blessed to only own homes built since the '80s!

          Hey, if they're using the ground as the antenna, though -- your EMT should be grounded and hence radiate nicely. They might not be though. This is /., I didn't RTFA.

    • Won't matter much unless the homeowner doesn't actually USE those wires. Every outlet is designed to have something plugged into it, and there are damn few home appliances that uses shielded power cords.

      The title of this article, however, is misleading. This is NOT about "making your house wiring into a giant antenna" it's more like "making your house wiring into a giant network cable" in the "luminiferous ether" sense of the word. The house wiring isn't there to be an antenna, but to be a passive media to

  • I recall stories of products that served to make an antenna out of the electrical wiring of your house or even the chicken-coop wiring in the backing of old stucco-surfaced walls. they functioned as advertised, but seeing as neither was designed for the purpose, they're both woefully unprepared for the accidental circumstance of a larger EMF pulse. recieving a signal incurs resistance, resistance heat. too much signal can suddenly cause your house to explode into flame.


  • by RomulusNR ( 29439 ) on Thursday September 16, 2010 @06:28PM (#33605260) Homepage

    When I was in college, kids in the university's then-tallest building would not bother getting cable service, which the dorm was pre-wired for. But despite not having cable service, they plugged their TV's into the cable jacks anyway -- and it increased their OTA reception fourfold. The cable wires running through the building served as a huge 100-foot antenna.

  • The benefit this project brags about is how the wireless nodes will consume so little power that the builtin batteries will deliver power longer than their 10 year shelf life. That's not really "eliminating batteries" as they claim, because actually eliminating batteries would mean the sensors would have an indefinitely long life, not one limited by the shelf life of the batteries.

    But since the nodes are using the building electrical power network for transmissions, why not just plug them directly into the

  • A trivial upgrade, assuming you have the right building materials. Just use some cold-riveted beams with cores of pure selenium, magnesium-tungsten alloys, and gold plated bolts, and it'll be working in no time.

"In the face of entropy and nothingness, you kind of have to pretend it's not there if you want to keep writing good code." -- Karl Lehenbauer