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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."
by the time they finish all the testing and modifying the existing power line, gigabit wifi will be readily available.
This Sig is removed due to factual inaccuracy
Let me guess; the modification is to glue a fibre-optic cable onto it.
Instead of spending all the money to rig up all the power lines to support this technology, and potentially causing substantial problems with interference to radio communication (particularly amateur), why not just spend the money on a stronger fiber infrastructure, which presumably can support a great deal more bandwidth than this, and doesn't have the problems with causing or recieving such interference. Why not keep our data and power networks separate, and optimize both for their specific purpose?
No other implementation has done as well, so far. Last I heard, many radio hams were actively working against broadband-over-powerlines, because it would be lethal to the frequencies they use.
Besides which, given the sheer number of grid failures (one this week, in fact) due to cascading power station shutdowns after a single cable gets damaged, I'm not sure I'd trust the power companies with handling large amounts of data.
That's not to say I think data shouldn't be sent over the grid. I think that it would be entirely possible to use such a mechanism to allow the grid to proactively route power the same way the Internet can proactively route packets. Use data over the grid to carry routing information and the states of lines, switches, etc.
You could then avoid catastrophic grid collapses, because problems could then be treated locally and immediately, isolating the failure, rather than allowing it to propogate through the system.
THAT would be a good, viable, practical use for this technology. Carrying P2P data, which then gets blasted over the landscape to everyone, whether they want it or not, is not.
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As a person employed in this industry I've done a bit of research on this topic. Basically one of the major challeges next to powerline interference is the cost of putting a bypass on the transformers. The signal being sent tends to be blocked by the coils.
There have been a number of solutions implemented such as using a bypass for the signal or Wireless to send the signal across the coils but they tend to be expensive. If you have a large number of transformers and have to retrofit each of them with a bypass then you could end up with a huge cost. Especially in places like Canada where we tend to have less customers per transformer than a place like Europe.
If a cheap solution can be devised though the benefits of such a solution could be huge. Having automated meter reading and providing internet service to customers can be a boon in cost savings and additional revenue streams (but of course retrofiting the meters also costs alot as some of the cheapest solutions I've seen on the market cost 1000 dollars per meter).
I hope some innovative person comes up with a solution to this problem someday in a cost effective manner. The coverage that a power company has for a customer base easily rivals that of the telecom industry and with more choice comes cheaper ISP rates due to the added competition.
A) It needs to be frequently repeated in the real world.
B) Sending data over unshielded high voltage lines is messy.
C) It uses very low frequencies where even the slightest signal leaks can interfere with radio's hundreds and thousands of miles away.
Most BPL trials in the US have been a disastaster. It is a "marketing technology"
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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.
There's already a trial in Australia for IP over powerlines at 200Mb/s. Article at http://www.pcworld.idg.com.au/index.php?id=1826952 087&fp=2&fpid=1
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Clue: All signals are waves. (Fourier)
Clue #2: All electrical signals are electromagnetic waves. (Ampere)
Clue #3: Electromagnetic waves are not contained in fields, they are the fields and the fact that that energy has formed a field means that it is no longer in the wire. (Faraday)
Clue #4: To keep these waves from forming fields of radiation, we can place an opposing (balanced) wave near it, twisting it occasionally (twisted pair), or we can place it in a faraday cage (coax).
Clue #5: Neither of these methods are used with power lines.
How much interference is released appears to be very debatable.
Clue #6: How much interference is released can be calculated, or observed through experimentation.
Clue #7: "Reality must take precedence over public relations, for nature cannot be fooled." (Feynman)