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Wireless Networking Power Hardware

Forty-Five Mile Wireless Tech For the Smart Grid 77

Posted by Soulskill from the enough-bandwidth-for-tradewars dept.
holy_calamity writes "San Diego startup On-Ramp Wireless has put together a proprietary protocol that sends data over 2.4GHz (like WiFi) but over distances of up to forty-five miles. Links using the technology are slow, 50bps at most, but could reduce the cost of smartgrid deployments. Connecting up home energy meters today requires using cell networks or unlicensed spectrum with much shorter reach."
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Forty-Five Mile Wireless Tech For the Smart Grid More

Forty-Five Mile Wireless Tech For the Smart Grid

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  • With a 45-mile line-of-sight link, sending 50 bits/s is hardly an achievement, especially when the antennas used are not specified. With a data rate that is "roughly 100,000 times less than the average U.S. broadband speed of five megabits per second", each bit has roughly 100,000 times more energy than bits in an "average U.S. broadband" signal -- which has the disadvantage of having to traverse a non-line-of-sight path.

    On-Ramp Wireless may have some interesting technology, but this is not the way to adve

    • "On-Ramp Wireless, delivering 1960s network speeds to today's users!"

      Perhaps it could be made more palatable if sung by an animated chipmunk.

    • the interesting stuff would be to know how many such nodes you could fit on 10km x 10km square and still have the one's in the corners able to talk to each other. and what kind of chips you need for it? because, cellphone networks sound much better suited for the power meter etc use mentioned..

      • I think the important issue here is for the outlier nodes. Ie, cities and towns are covered reasonably well but current technologies, even many rural areas. The hard part is the remaining 1% of nodes that are in hard to reach places, places where even cell technology doesn't reach well.

    • Re: (Score:2)

      by tulcod ( 1056476 )
      My thought exactly. Why would you need 2.4GHz to send 50 bits per second? This better works on solar power, in the container of a nuclear reactor, even if you remove that big black squarish thing from the green plate. There are /very/ simple rules to design a radio frequency communication system, and this is impressively unimpressive.

    • Re: (Score:1)

      by Anonymous Coward

      Nothing in the article mentions either a line-of-sight link, or that any special antennas are required.

      This isn't a new wireless broadband technology, this is an example of a technology which solves a very specific problem. It's not one that most normal people will ever encounter, but that doesn't make it a bad thing.

      • Re: (Score:2)

        by Rei ( 128717 )

        Exactly. It sounds like the goal is to use commodity hardware (read: cheap) but with extreme error correction levels to handle attenuation factors hundreds of thousands of times greater than traditional wifi (at the cost of bandwidth which isn't needed). They could probably make the things for $15 a pop and cover the whole country with $500k worth of hardware (plus installation, plus profit).

    • Re: (Score:3)

      by Rei ( 128717 )

      Typical wifi ranges with a clear line of sight are, what, 300 feet or so? 5280 * 45 / 300 = 792 times normal wifi range. With signal strengths dropping off proportional to distance squared, that's an attenuation ~630k times greater. And you're complaining about 1/100,000th the bitrate?

      Furthermore smartgrids don't need high bitrate. It's irrelevant to them. So what's the point? What they need is a widely deployable, low cost solution.

      • It really depends on the antenna required. I've run 50 mile links with 802.11g/2.4ghz that ran at full speed -- it's not difficult. If this product does it without requiring 4 foot antennas 250-300' in the air on both ends.. great.

    • This is absolutely nothing new.

      You have always been able to trade bandwidth to distance in any radio link. Having said that, there are certainly telemetry and remote-monitoring and control applications aplenty.

      But revolutionary, it is not.

    • Re: (Score:2)

      by Bengie ( 1121981 )

      The 2.4ghz range is full of noise from wifi to microwave ovens. It also is readily absorbed by humidity/water.

      No one actually uses 2.4ghz except home based wifi because it's such a bad frequency to use. It's the dumping grounds for ad-hoc networks.

  • Next stop, Dropping your phone for iPod VoIP service.

  • I hope this isn't another service which may impair other devices working in the 2.4GHz range. That's got to be a strong signal.

    • I think that's the point. It's probably not a strong signal. There are rules you have to play by if you want to run in the unlicensed spectrum. If they can manage 45miles (even at very low speeds) while not having to jump through any new regulatory hoops, or license spectrum, using easily installed / cheap hardware, then that may be the "breakthrough". That said, I'd guess they're probably maxing out what is allowed to get that 50bps. So expect at least the same amout of interference as from any other

    • I hope this isn't another service which may impair other devices working in the 2.4GHz range. That's got to be a strong signal.

      Nope. It trades distance for bandwidth in an age-old manner. It's just one of those Radio things that most people never learn or have forgotten.

  • So I could DOUBLE my speed with a 110 baud modem?
  • I don't understand why you would use something with this kind of range in an unlicensed band.

    You are basically setting yourself up to fail when you get interference all over your supposed coverage area.

    • Re: (Score:2)

      by Ruke ( 857276 )
      I believe that the point is that they're setting themselves up to succeed where there is already a large deal of interference. The interesting part of this technology is that it is built for situations where the signal-to-noise ratio is significantly less than 1. Sounds to me like someone read Shannon's Theorem, and instead of saying "How much capacity can we squeeze out of this?" asked "How high of a signal-to-noise ratio can we tolerate before the capacity drops to effectively zero?"

      • Re: (Score:2)

        by theVP ( 835556 ) *
        Okay, but, again, why an unlicensed band? If this is for utility companies to use, and has a large over-reaching benefit to all sorts of communities (many of them owning or running the utilities), why wouldn't there be cause for a licensed band? I understand the intention, and the expectation that this will work anyways, but why not just make sure by using a licensed band instead?

        • Re: (Score:2)

          by h4rr4r ( 612664 )

          $$$$, that is why. If you only need 50bps and you can get it on unlicensed spectrum, why pay for licensed spectrum?

          • Re: (Score:2)

            by theVP ( 835556 ) *
            Because when it stops working in some communities thanks to the interference that this supposedly slides under, you'll stop selling it in others.

            However, if you were to start off in a licensed spectrum right off the bat, you could sell the tech to just about every utility company in America.

            I am, of course, assuming they intend to make more than one in the future, and have more than just one customer.

          • Re: (Score:2)

            by dtmos ( 447842 ) *

            why pay for licensed spectrum?

            ...because then you can expect the noise floor at your receivers to be determined by your own receivers and can (at least in theory) complain to the relevant regulatory body if you experience harmful interference significantly in excess of that level. In an unlicensed ISM band, a homeowner can turn on a microwave oven, Wi-Fi AP, or other transmitter a foot away from your receiver, and you can't do anything about it -- other than wait for it to stop. Under very common ISM band interference conditions, you

            • Not their SCADA networks, but things like meter reading, sure. If they can only read your meter between 2 and 5 AM while most wifi use hits a lull, that's fine.

    • Re: (Score:2)

      by NetNed ( 955141 )
      You missed the key to the last sentence, home energy meters. There are many stories of people getting hit with bill as much as 10 times higher after a smart meter is hooked in to a home. The power company does nothing to explain it other then telling the people to pay their bill or go without electricity. Read one story of a 900 sq. ft. home getting charged $1000+ for a month after the smart meter was hooked up when the average electric bill was $128 for years and years. The Power company sad that's what it

      • The problem with these stories is that they are anecdotal. I'm sure some happen, but there really are ways for professionals to measure what is going wrong and I'd like to hear their report.

        If your smart meter works like mine, you can walk up to it and get the reading. Once that happens, you can tell if it's the local meter having trouble, or the remote software. If the local meter is having trouble, the next step, unfortunately, requires some technical sophistication. A temporary power has to be installed.

        • Re: (Score:2)

          by NetNed ( 955141 )
          Anecdotal? There has been many stories of people being massively over charged and the power companies coming back and saying that's not their problem. That is why their is a opt out program in California, because SO many people had issues with the meters and complained to their representatives that the state house there forced PG&E to have a opt out program. If it was a glitch and it was corrected, that's one thing, but this was a power company that didn't want to admit the glitch because it favored the

          • Despite the fact that there were a lot of complaints, paranoia about the low-power radio's health effects, and PG&E had an opt-out program forced upon them, the only difference for people who opt out is that someone comes to read the same number from the face of their power meter that would be transmitted by radio.

            There is a lot of stuff that people "know" that isn't really evidence. Like all of those cars that have out-of-control acceleration - it was Toyota Prius a while back, and Audi Quattro before

  • The technology can even pick up signals that are weaker than the surrounding background noise

    It sounds like they reinvented JT65 [wikipedia.org].

    -molo

  • Bandwidth and Time vs. Range trade-off (Score:5, Informative)

    by Bruce Perens ( 3872 ) <bruce@perens.com> on Monday June 27, 2011 @02:33PM (#36587290) Homepage Journal

    The application for this is reading power meters and other continuous but low-bandwidth data. These generally operate in a mesh network. The devices used are generally low-cost and low-power, often in the "Part 15" section of the FCC rules for low-power devices that aren't allowed to interfere with licensed services. The problem is that some homes are too far from any other to link into the mesh, and the expense of reading those meters goes up significantly.

    Signal processing theory allows you to trade bandwidth and time for range, such that a signal with a wider bandwidth or longer duration can be received over a greater distance. Hams have been doing this for decades using ultra-low-speed morse, PSK31 [bi.ehu.es], and other digital modes.

    The achievement isn't really getting a long-range link, you can get 45 miles between mountaintops with wifi and parabolic antennas on a clear day. The achievement would be doing this for a very low installed parts cost and in unlicensed spectrum (which also reduces cost) while avoiding interference from wifi etc.

    • Exactly! I mean people would know this if they read the article but this is Slashdot...

      Basically right now they would not be able to do away with cell phone based radios in smart meters unless this device allowed two different connection modes. This is because 99% of the time data flow is low and can be delayed with no real consequenses. However less then 1% of the time the meters get firmware updates over the air and this does require some decent bandwidth especially in the mesh architecture.

  • WiFi goes further (Score:3)

    by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Monday June 27, 2011 @02:34PM (#36587300) Homepage Journal

    Isn't the record for WiFi over 100 miles with amplifiers?

    Isn't the record for WiFi about the same as this without amplifiers, just using bigass dishes?

    Is there any actual need to have quite this much range for this particular application? Wouldn't it make more sense to just use mesh networking? Wires don't tend to run 45 miles into nowhere to serve a single customer.

    • I'm personally in favor of mesh, but I'll say this... no, I don't want yet another dish on the side of my house. This could have uses, though, thinking nautical.

  • When I was growing up we would have just walked there. In the snow. Uphill. In both directions.

  • I tried to work out a way to semaphore at 50bps, but it can only be done if you prepare lots of colored flags lined up on a table so you can quickly grab the right one. That seems like cheating. The best practical one-person encode for just waving flags I can find is 9 bits per second. If you had six people waving flags at once, though... that would do it.

    More seriously: Why is this being done in 2.4? Even if the customer utilities are too cheap to licence a little spectrum for themselves, there are ISM ba

  • Gee (Score:4, Funny)

    by bugs2squash ( 1132591 ) on Monday June 27, 2011 @02:57PM (#36587594)
    if only we could find a way of connecting to all of these electricity meters with wires somehow...
  • Why do they need to be wireless? They're coupled to an inherently wired technology, can't they use the power wires to transmit the signal? Isn't that how smart power meters work?

    • Some power companies are wiring the smart-grid backbones with fiber optic. Aside from serving their needs it's also a sneaky way of putting a consumer WAN in behind the established players backs.

    • Some smart meters use PLC, but it's a really lousy technology for some of these purposes. Wireless works a lot better and most smart meters and smart grid applications use that. Even then there is no one-size-fits-all solution. (note that smart meters and smart grid are not the same things, there are also distribution and transmission devices to monitor and control, and gas and water meters as well)

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