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Gigabit Transfer Rates Over Power Lines?
nomrniceguy writes "Penn State engineers, Pouyan Amirshahi and Mohsen Kavehrad, estimated in a research paper released Wednesday that their system could deliver data at close to one gigabit per second over medium-voltage electrical lines in ideal conditions, with speeds of hundreds of megabits per second available to home users.
Their system would uses repeaters placed every one kilometer, (0.62 miles) and requires power lines to have been modified to reduce interference with the data signals. The engineers said their estimates were based on computer models, and that the data speeds available in a real-world version would depend on how many repeaters a power company used."
Any idea about what kind of modulation they are planning ? QAM ?
- People who believe other people have no right to live, got no right to live ...
From the article, I do not see the cost effectivness of boradband over power lines.
Also, would bells start suing for unfair competiton?
Some call me Howie Feltersnatch
The engineers said their estimates were based on computer models, and that the data speeds available in a real-world version would depend on how many repeaters a power company used.
Even if this system can be as good as these Engineers seem to think, it never will be, as the power company will only place repeaters at locations that can cover the most area, leave people on the outskirts with minimum service at the same price, just as current broadband companies do.
I do however doubt that we'll see this any time soon, as the article stated they would also have to alter/replace many existing lines in order to implement it. One of the key reasons this was ever considered in the first place was that it could use lines that already existed.
Go ahead and call me unreliable; reliable is just a synonym for predictable.
It could possibly serve some extremely remote areas where there simply are no other options, though still someone has to pay for it, and I expect even a DS3 would be cheaper.
How am I supposed to fit a pithy, relevant quote into 120 characters?
I'd like my sine wave nice and clean, thank you. I'd also like less EM in the air.
http://www.arrl.org/tis/info/HTML/plc/
It doesn't really seem to solve rural broadband roll-out problems either. Repeaters every few miles only goes so far, so this may still be constrained by the same population density issues as DSL and cable. I'd think that rolling out WiMax would be easier and cheaper, assuming that it lives up to claims and can be mass produced affordably.
If you guys won't RTFA fine, but at least read the summary. This scheme includes modifications of the lines to eliminate the interference problems.
Now debate the costs of replacing the lines, debate the speed, debate whether it's ethical to send nude shots of your gf over the same lines the power Grandma's toaster. But for the love of god quite repeating the same damn statement about RFI again and again!
This system would shoot AM radio in the head.
It would destroy any chance of using Ham radio near it.
It would be a disaster.
I know that you can hook up an AM radio transmitter to a rail road track and broadcast the whole lenght of the thing. This is very illegal because it bleeds on any one else using the same frequencies.
Just because you can do something doesn't mean that you should. We have a clear case of people trying to create something new just because they can. They don't seem to care if they tinkle on any other form of RF communication.
Coax or Fiber makes much more sense. But because power companies are run by very rich and powerful people, they will try to get on the bandwagon of providing bandwidth to the home.
If we are going to use RF frequencies in the open air, without the benifit of shielding then we should persue P2P wireless and a bittorrent type of system. Each person would have a node and the node would both transmit and recieve. People would know where you are based upon location, and then the data would be funneled to you with low-power transmitters that would work P2P.
there would be no need for a central hub. There might also be no way for any utility to charge you for this.
That is exactly why this kind of a system doesn't get built.
And at a neighboor hood you could have it all funnel into a local broadband internet for a bunch of houses. The antennas would be directional and beam directly between each other.
Let's all hope that this idea of using the unshielded powerlines to transmit data is shot down by the FCC.
Isn't the real value of the power companies the right-of-way they possess for all of these power lines ?
Why would they install repeaters every 1 km ? I just can't believe that it would be that much cheaper to do that instead of just running fiber next to the power lines instead.
Then you'll get > 1GBs without even breathing hard, you'll only need a repeater about every 20km or so, and there will not be any RFI/EMI problems.
Power lines make _terrible_ communication channels.
Absolute statements are never true
...get interrupted by an unlucky squirrel.
There's a sicknening reality to this. I used to bitch about having mediocre power from Omaha Public Power District (OPPD). They were pretty slow getting to the problem and I had encounters where they'd get there, only to sit around for three hours waiting for a "safety foreman" to show before they could restore power. In retrospect, I was just impatient like most power customers.
Then I moved to MidAmerican Energy territory. Oh my god. Serious, total suck time. Treynor Iowa (east of Omaha) has gone down at least a half dozen times this year for, um, squirrels, bunnies, sunny days, a cloud, etc. They joke about outlawing rodents because apparently their appearance causes half the county to suddenly not have power. My little town lost power three times this fall - for hours at a time - for nothing anyone could ever figure out. MidAmerican doesn't tell usually (you have to find a lineman to share the secrets, apparently). Someone told me that Warren Buffet (fat cat second richest guy in the world or something that lives in Omaha who tries to convince people he's a nice little guy, but if you knew him and his "family" you'd know better) and his company, which own Midamerican Energy, have been doing the Gorden Gecko on their maintenance. You know the Wall Street Movie where the guy slaughters the company to sell it off in pieces. Since the linemen say the same thing (one truck on call to cover two counties on weekends), I kind of wonder.
The funniest one was this last September. I was working in my shed and needed more light. (I live on a farm a couple miles down the road from my little town). I grabbed my dual-500 watt halogen and plugged it in. On... OFF! Crap. Thought I popped the breaker. Reset it. Nope. Whole damn panel was down. Went to the pole outside my shed and reset. Nothing. Went to the main pole that feeds my outbuildings. Reset. Nothing.
Turns out my plugging in a light TOOK AN ENTIRE COUNTY DOWN! We were down throughout Monday night football. Didn't get up until 10:30. What did MidAmerican Energy say? Nothing. They don't even call you back when you select the callback option. So apparently using 1000 watts is enough to shut an entire county down. Holy freaking cow.
I've asked one of their engineers why their power is, um, so, um, not reliable. His answer? "You live in the country. What did you expect?"
I pray my Internet never, ever depends upon these complete fools.
Who needs this data transmission over power lines? No one in North America!
There are millions of meters of 'dark fiber' in the ground already. This is the ultra high bandwidth fiber optic cable that was put in place quietly by the utilities during the boom years of the 1990s. It was all this unused fiber-optic capacity that gave rise to all the talk about video-on-demand and other high bandwidth predictions at the time.
Maybe somewhere, someday, somebody could make use of this technology. But for the present, it's just an academic exercise.
The problem with getting bandwidth into use in North America isn't technological, nor is it the lack of installed cable. It's political. Everybody involved is just too damned greedy and the end result is that nothing much happens. It's like crabs pulling each other back to the bottom of the bucket.
I know it's bad form to reply to trolls, but on the odd chance this guy meant well but was just uninformed, I'll play:
Wait until after it DOES cause interference, then denounce it as a bad technology. Don't tell me it might cause interference, let me show you that it doesn't! (or at least, doesn't have to)
Actually, would you believe a bunch of engineers actually engineered something before they spoke up? Well, I would. Engineers are usually such intraverted geeks that they're the last people to complain (until they've run it through forwards, backwards, sideways, etc.). That is exactly what happened with BPL and hams (amateur radio operators).
Our organization, the ARRL, studied this because the FCC was, um, preoccupied. Please check out all the research and analysis data on this and you will see we've overengineered, as usual. Any management type would have screamed "I get the point" long ago, but the hams like to be complete.
Simply said: it does not work. It has to do with how physics are engineered in our universe. Saying "well, I'm sure they'll find a way" is relativistic, wishful thinking that unfortunately violates the laws of nature. I had to deal with a city councilman who opposed towers higher than 40 feet because he didn't like the look of them. There is a radiofrequency physics concept called "takeoff angle" which has to do with the height of your radiating element above ground and the subsequent direction the radiowaves will travel. It is totally dependent upon the frequency you are using. For frequencies like 40 meters, 80 meters, etc., if you have a short tower, your signal goes straight into space. Takeoff angle at work. You MUST have a higher tower to keep the signal traveling along the horizon.
I apologize for the geek talk, but please understand we hams use this takeoff angle and other physics to do things like provide communications for disaster victims. Here is an example of this help. Yes, our hobby is saving your ass (and others). It is how we pay for the priveleges we have with frequencies. There is great honor in helping other people out with the skills we have. And un-educated persons that push bad ideas like BPL without understanding the consequences are like a drunk in the cockpit of an airliner with 350 people aboard - we geeks will get upset at this because you don't know what you're putting at risk. Please don't take our anger personally - but understand you don't have a clue what you're talking about.
Anyway, this councilman (a used furniture salesman... go figure) was insistant on prohibiting towers of the height necessary to keep the takeoff angles near the horizon. His response? "I'm sure science will let you guys be creative and figure out a way to make a short tower do the same thing."
People who do not understand physics are a danger to any engineering project. So friend, when you complain that engineers have pointed out that BPL will do exactly what it is designed to do - that is, radiate RF all over the spectrum and cause the USA to be the worlds polluter of RF - don't attack the messenger. If you've figured out a way to break physics, let us know. Otherwise, read up or shut up!