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Broadband Over Power Lines vs. Radio Relayers

amaiman writes "Recently, broadband Internet access has been increasing around the country. These broadband signals, while providing Internet access to remote communities that would normally not be able to receive broadband, are causing enormous interference to the radio spectrum. This article details some of the problems, and a video available on the American Radio Relay League's (ARRL) site shows exactly how much interference the broadband power lines can cause. Detailed information is also available on the ARRL site."

21 of 147 comments (clear)

  1. But I thought... by DAldredge · · Score: 5, Interesting



    But I thought that hams where saying that BPL would destroy radio communication for 100's of miles around? This video only shows the effect when they are very near the powerlines.

    They also play word games by saying it is on the agenda at the FCC. On the agenda doesn't mean that they will approve it, it simply means they are looking at it.

    Lastly, it doesn't help hams when hams say they will just pump out a 1kw signal to drownout the BPL signal, that action will simply result in the group with the most votes winning, and that isn't the hams.

    1. Re:But I thought... by TWX · · Score: 5, Interesting

      "Lastly, it doesn't help hams when hams say they will just pump out a 1kw signal to drownout the BPL signal, that action will simply result in the group with the most votes winning, and that isn't the hams."

      You forget that amateur radio is the primary user on said frequencies. This means that if their broadcasting interferes with your Part-15 "This device shall make no interference, and this device shall receive interference, even if it causes undesired operation" broadband service, tough shit. This doesn't mean that ham radio operators are out to screw over the world, but many, many operators have very powerful rigs and won't really be very worried if you try to move into their territory on the spectrum.

      I wonder if anyone has looked into how this'll affect business band radio, which is often on frequencies near amateur radio. That'll be an interesting one, since those users are specifically granted commercial licenses on those frequencies for communication purposes...

      --
      Do not look into laser with remaining eye.
    2. Re:But I thought... by dougmc · · Score: 5, Informative
      And if very many hams do what you suggest the laws will be changed and those hams will lose their licenses and have to pay fines.
      Perhaps, though that would require that the law change. Currently, the hams CAN legally do this.

      Note that it's only a *very* small subset of the ham community that's even considering deliberately jamming BPL. Most hams are considerate to a fault, and wouldn't retaliate like that.

      But for now, if you need to use 1500 watts to make a contact, it's legal for a ham to use 1500 watts to make that contact (on most bands), even if it causes problems for BPL. The law says you need to use the minimum amount of power to get the job done, and most hams do that. But if you need 1500 watts to get the job done, then you can do that.

      (For the record, I'm AD5RH. And I don't have any equipment capable of putting out over 200 watts.)

    3. Re:But I thought... by Anonymous Coward · · Score: 5, Informative

      Look out your window - every amateur radio operator who lives within a couple hundred yards of a powerline will be affected. Not only that, but, according the the ARRL site, rural emergency radio communications (Fire Department, Ambulance, etc) will also be affected. Don't forget, also, that the frequencies that we're talking about are used by amateurs to provide emergency communications during natural disasters, health and welfare traffic, as well as comms during public events like marathons, bike races, parades, etc.

      BTW, it's not a matter of pumping up the transmit power either. It's on the receive where BPL causes the biggest problems. You're already trying to listen to a whisper in crowd, and BPL is like an obnoxious car salesman with a bullhorn.

    4. Re:But I thought... by lku · · Score: 5, Insightful

      Yeah, if it just were the hams who are against BPL.

      There are far more users on the HF-band than just the hams. There are "small" communities like military and air traffic who are opposing BPL as well because it would also ruin their ways to communicate over a long distance without dragging cables with them or to have many radio relay stations along their routes.

      Of course then there is satellite communications, but I don't think we will see gear suitable for, lets say, spec-op -troops to carry with them all the time to provide them reliable enough way to communicate with others like they can do with their small HF-radios.

      And what about emergency situations? All communications and power is cut out for large areas. How would you call for help? Via radio, of course. But because of BPL nobody can hear your scream. "But hey", you would say, "then there will be no BPL around to mess with the communications". Yes, but there where the power and communcations, and the help of course, is, there might also be BPL so it would be hard for them to receive your message and your critical help might not arrive in time.

      No, don't think me as an enemy of technology even after this. BPL is good technology, but at the moment I can't keep BPL mature enough yet to be used for what many are willing to use it now. It may be great technology for a last mile or to be used inside the building, but over airlines (or what ever you call telephone wires hanging on poles) for long distance not. Some European countries (e.g. Germany, IIRC) have banned BPL because of its interferencies and on many more countries it hasn't started to become popular because there has been more problems than success with current BPL technology.

    5. Re:But I thought... by aldoman · · Score: 4, Informative

      I just got an arrl newsletter telling all of their members to contact their congressmen and tell them what a bad idea this is. Apparently, according to ARRL research, broadband over powerlines causes significant interference not just in ham bands but across the spectrum. Although I havn't exactly looked at the research in detail, I can't see how the power companies could avoid interference. Powerlines aren't shielded, and for any reasonable bandwidth to be passed through the powerlines, the frequency would have to be high enough that a significant amount of power would have to be used. Unshielded wire is always agood antenna, and for some situations the best. Granted it won't be well tuned, but I've seen worse situations cause a lot of interference. My home is near high voltage power lines (read a large part of San Francisco's power) and even at 60hz, I get interfering harmonics all the way up into 10 meters. Avoiding electrical grid contamination is something every ham has fought with. Hopefully I'm wrong, but unless there is some way of preventing interference, this seems like one of those thngs that will be really good for pacbell and really bad for the rest of the wireless world.

  2. Yet another example... by ErichTheWebGuy · · Score: 4, Funny

    ... of why the FCC is so damned ineffective. I thought the FCC was commissioned to prevent just this sort of thing? Apparently these days it is only another government hypocricy that panders to the highest-paying lobby.

    --
    bash: rtfm: command not found
    1. Re:Yet another example... by ErichTheWebGuy · · Score: 4, Interesting

      It isn't just the pro bpl side playing games.

      Good point. And it further reinforces my argument that the FCC needs to get their act together and stop pandering to people who play these silly games.

      Just like, oh I think it was Clear Channel that tried to get XM to stop broadcasting local news because it interfered with the local market. Translation: When you cannot compete fairly, get the government involved and shut down your competitors.

      --
      bash: rtfm: command not found
    2. Re:Yet another example... by danimal67 · · Score: 5, Interesting

      I'm disappointed that the FCC even cares about HAM radio operators. FEMA, NTIA, and the Department of Homeland Security have all filed with the FCC proposals 03-104 and 04-37 in favor of BPL if reasonable precautions are taken. These are the govenment agencies HAMs have been saying will be crippled if BPL is deployed. Nowhere in their replies do they spew the doomsday scenarios that HAMs are putting forward to scare people regarding BPL. HAMs love to overstate how critical they are to the communications infrastructure in emergency situations. Nothing I've read yet in reference to emergency situations can replace the following benefits in my mind: BPL can be used by power companies to provide -Intelligent Demand Side Management -Load Switching/Balancing -Fault Locations -Peak Shaving -Power Quality Monitoring -Real-Time Pricing For consumers it can provide -Video on Demand -Content -Alarm Monitoring -Smart Appliances -Broadband -InternetTelephony DS2, a BPL chipset maker has 200mbps chipsets that are working in the field now with a company working with ConEd called Ambient. My point is, even if the HAMs were completely deprived of their use of the HF spectrum (which by every government agency's accounts they won't be), I strongly believe that the benefits of a smarter power grid combined with a third major competitor for broadband outweigh the loss. I am very biased however as I'm heavily invested in Ambient, so take that into account when you read my reply. But look at the FCC replies for yourself to make up your mind before you believe either me or HAM users. Go to http://gullfoss2.fcc.gov/prod/ecfs/comsrch_v2.cgi type in 04-37 or 03-104 in proceeding and educate yourself more about the issue.

    3. Re:Yet another example... by sharkman67 · · Score: 4, Informative

      Hmm, did I see you down at the World Trade Center site during 9/11 and the following weeks? Didn't think so. Us Ham radio operators (I came in from Connectucut) were down their providing communications in 24/hr shifts. I provided over 48 hours of service. If you were not so ignorant as to what we do and who we provide service for you wouldn't be so quick to open your mouth.

      Now imagine there was some kind of full scale attack on the US where multiple cities were affected. Phones are out, cells are out (or like during 9/11 useless) forget the Internet and your lucky to even have electricity. Hams are no longer operating on HF because some short sited people, who are more concerned with their stock investments, got BPL pushed through. Who is going to provide not only local but long distance communications? You?

  3. Seriously by challahc · · Score: 4, Interesting

    This article is 4 months old. In March the power company Cinergy in Cincinnati started offering broadband over powerlines. I havn't heard much about that since then, I really would like to hear something about that. Is it still around? Is anyone using it? Are there any complaints?

    --
    01100010 01101001 01110100 01100101 00100000 01101101 01100101
  4. This is so old, it should be the other way around by CrystalFalcon · · Score: 5, Funny

    The latest RFC don't deal with broadband over power lines any more. It's been tried, and power companies have folded over this bet.

    My own power company gave up and found it more efficient to simply lay TCP/IP fiber along the new power lines instead.

    No, the new thing is not TCP/IP over electricity lines, but electricity over TCP/IP lines, as detailed in RFC3251.

  5. What about good old lasers? by Anonymous Coward · · Score: 4, Interesting

    On a previous project we used point to point optical
    units, I remember the output was only a few hundred milliwatts but we were p2ping 5Km or more in fair
    visibility. Surely optical wavelenghs are not restricted and civillian versions of this sort of
    optical tranciever are available? Someone has to line them up at installation, but its as easy as doing a microwave dish. I think a network of point to point laser trancievers would be ideal for remote raural coms in the out back and beyond. With this kind of power efficiency repeaters would easily run from solar cells. What think the /.ers?

  6. February is old news - what's happened since then? by billstewart · · Score: 4, Informative
    The article's from February. Here's the January Slashdot Discussion. Has anything new happened? In particular, how are the recent discussions about using powerline data transmission to feed 802.11 local distribution going? That offers a lot of potential to reduce the amount of wired transmission that can cause interference.

    Articles about BPL that get technical often bring up comparisons between how it works in the US vs. Europe. For various historical/technical evolution reasons, including population densities, the two sides of the pond have much different concentrations of number of users per power transformer, and supposedly the technology makes a lot more economic sense in Europe. In the US, one of the more interesting markets is rural access, where distances are too long for DSL and cable TV isn't very common - satellite's an obvious alternative, but satellite latency is annoying. Non-Amish farmers have tended to be fairly wired for a long time - the commodities and futures markets have a major impact on how you can get the best price for your crops, and even old modems and Apple IIs were good enough to get trading information and text-based weather reports, but more bandwidth is always better.

    But the other obvious market is that it's another wired or near-wired access method to get bits to your house, besides the Phone Companies and cable modems, which means it increases competition for the phone business as well as data business. Power companies already have a certain amount of potential simply from owning right-of-way, though sometimes the phone companies own the poles, and state Public Utility Commission regulators often create all kinds of strange rulings about who can do what with the shared assets (a problem cable tv companies have had, especially when they want to sell bandwidth on the fibers they run in shared right-of-way.)

    --

    Bill Stewart
    New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
  7. Re:Have it already by dougmc · · Score: 4, Informative
    Here in Cedar Rapids IA, we already have it, i can go and see the units themselves mounted on the powerlines, and pick them up with kismet and netstumbler along glass road.
    Eh? BPL is typically between 2 and 80 mHz. Higher frequencies will be attenuated too much over powerlines to make their use pratical. kismet/netstumbler is for WiFi, 2400 mHz -- MUCH higher than 80 mHz.

    If you can pick up these boxes with these tools, then these boxes are not BPL., unless they're some sort of bridge between BPL and WiFi, or can be managed via WiFi or something?

    Aha ... google to the rescue!

    I just received word a few days ago that Alliant Energy is planning a trial of BPL in an undisclosed part of Cedar Rapids, IA, sometime this year. No specific dates available, but within the next 3 months. The plan appears to be using the 13.8 kV lines to carry the data to various neighborhoods, and then use 2.4 GHz WLAN servers to connect between the HV lines and subscribers.
    So they are bridges. Seems an odd way to do it though -- BPL CAN go all the way into the house (that's part of why people like it), so why are they using WiFi for that? If all they're doing is putting APs in each neighborhood, why use BPL at all? Just run standard cox or fiber optics to each AP.
  8. Cumulative effects by Alan+Cox · · Score: 5, Informative

    Shortwave radio communication over any long distance (commercial, military and hobbyist) often deals with weak signals. Each broadband power line adds to the background noise cumulatively raising the problem. One power line won't trash your TV signal (unless you are very close), but each one adds noise until all you have is snow.

    Its like people talking in the background - a couple of people don't do much harm but when you try and talk across a room full of quietly talking people two things happen

    1. The cumulative background noise reduces the signal
    2. You turn the volume up (as the amateur radio people will have to and although entitled too don't wish too because it causes other users problems)

    When you turnt he volume up, they all have to talk louder, so you get a fight between high and higher BPL power (to avoid radio wiping out internet, and higher and higher radio power for the same reason). At which point nobody can communicate usefully and lots of third parties are harmed.

    HF interference isn't just an amateur radio problem either - you might well find you get 802.11 dead zones if you are near a power line using it. You may not be able to use radio controlled toys in an area with too many power lines and so on. Finally HF is essential to things like flying medical services and some rural communcation systems.

    It all gets quite messy when this happens because good radio practice is the lowest possible power. The lower the power you can use the more people can use the same frequency. If everyone has to use 1KW then you'll get a lot less frequencies.

    I'd also say their description of the FCC is in tune with its historical decision making - just look at the monopolisation of US commercial radio and the continued unneccessary exclusion of most small transmitters which could exist and other countries have proved are not a problem. Of course BPL background noise might well wipe out the scope for very low power radio stations too.

    BTW: BPL trials in the UK (way before the US) were shelved for several reasons but intereference was a big one.

    It shouldn't be insoluble - one nice property of radio is that if you can get the BPL encoding frequencies high enough then the interference problems become much less of an issue.

    (PS: I defy you to find a radio astronomer who won't use expletives when asked abtut BPL..)

  9. BPL is the wrong technology at the wrong time by drwho · · Score: 4, Interesting

    Thanks, Slashdot, for this article. One the cat is out of the bag, he won't go back in...so it's important that BPL gets ripped out when it fails (which it will...oh yes we have WAYS of making it fail. For instance, all BPL ISPs will be filtered at my firewall. And I am a licensed amateur, and will file an endless stream of takedown complaints to the FCC, as hams ARE the primary users of the bands in question). So, doing whatever it takes to delay any implementation, on a local level, is appropriate. It would be a good idea for municipalities to ban it.

  10. The idea of BPL in it's current form is disgusting by Anonymous Coward · · Score: 5, Insightful

    There is only a fairly small frequency band in existence that can be used for inexpensive worldwide communication, and that is HF. The reason are more or less predictable Ionosphere layers that reflect radiowaves.

    Under good conditions, you can transmit halfway across the world, with just 1-5 Watts of transmission power. The Amateur Radio community knows this as "QRP" operation, and it is quite popular. So, yes, even small amounts of HF noise will go a long way to interfere with shortwave communication.

    20 years ago a sizable amount of communication was still being done by shortwave (HF) radio, and anybody thinking about poisioning large chunks of HF spectrum would've been declared a raving lunatic. Every kHz of HF spectrum was (and still is) a prized posession. Look up any frequency book from the 80's and you'll see that there wasn't a Hertz of HF spectrum unallocated, and it was (and still is) tightly controlled by international agreements. For large Radio stations (BBC, VOA), it is still the only way to connect to people in dictatorships and less advanced countries.

    Today, most commercial and military communication in the US has moved to satellite; Only smaller services (in the west), third world countries, radio stations and HAM radio operators use HF. Of course, why would large power companies care about other countries or the BBC news ?

    The HF spectrum is still the most valuable piece of electromagentic real estate there is in the World. Purposefully injecting additional noise into the band for no other reason than to save a few bucks is a terrible mistake and shows ignorance and recklessness on a staggering level.

  11. Very Important Thing by Pan+T.+Hose · · Score: 4, Informative

    A very important yet often overlooked thing to keep in mind while thinking about "broadband over power lines," as I have already written countless times with little effect, is the very fact that it all has started as a scam. The idea has been introduced by Luke Stewart, a scam artist who has promised more than billion gigabits per second (sic) with his "Media Fusion" snake oil.

    The idea of sending information via the electrical grid, rather than over telephone copper or fiber-optic cable, has been around for decades. The field, known as power line communications, or PLC, is pockmarked with wasted investments and technical failures. Only within the past few months have several companies begun to deploy limited PLC ventures.

    [...] Stewart, however, had a much grander vision, based on what he considered to be a dramatic discovery: Data could hitch a ride on the magnetic field created by electric currents running through power line wires. By piggybacking on this magnetic field, instead of on the electricity itself, he could obtain almost limitless speeds of transmission.

    [...] Media Fusion promised to deliver, within two years, bandwidth at speeds thousands of times faster than what's possible with fiber. Stewart was company chair, while the board of directors included government heavyweights such as former Speaker of the House Robert Livingston; Terry McAullife, a leading Democratic fund-raiser and close friend of then-President Clinton; and Admiral James Carey, former chair of the Federal Maritime Commission. The firm's Web site declared that the ASCM technology would "impact every facet of our life," and the computing power of the network would be "exponentially more powerful than any supercomputer to date." [emphasis added]

    This scam and those billions gigabits per second was the only reason why "broadband over power lines" has been ever considered in the first place. See these links for sources and much more informative details and background.

    --
    Sincerely,
    Pan Tarhei Hosé, PhD.
    "Homo sum et cogito ergo odi profanum vulgus et libido."
  12. Link by Pan+T.+Hose · · Score: 4, Informative

    I have found a direct link to the article I was quoting in my previous post, The Electric Kool-Aid Bandwidth Test by Evan Ratliff. It is long but very interesting and enlightening. True eye opener. Enjoy.

    --
    Sincerely,
    Pan Tarhei Hosé, PhD.
    "Homo sum et cogito ergo odi profanum vulgus et libido."
  13. Longer than 50 years by mjallison · · Score: 4, Informative

    The ARRL just celebrated it's 90th anniversary. Ham radio was around before that.