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Gigabyte Modems over Electric Lines
Ryan Wilshere writes "C|Net has an article on so called 'Power Modems'. They claim they can do Gigabyte transfers over regular electrical line. Dallas-based start-up Media Fusion has won a U.S. patent on a process it says can send data, video and voice over electric wires at speeds thousands of times faster than current high-speed Internet access technologies."
They keep on trying. We keep on hoping.
.. says can send data, video and voice over electric wires at speeds thousands of times faster than current high-speed Internet access technologies...
I think this right here is just media hype. Ive seen cable modem, and dsl which both keep getting worse and worse. I would have to see some benchmarks and actually see this project completed and tested before I would believe that this works. Every technology has its flaws, and right now its too early to see what this products flaws will be. I know that Canada has a high speed network going on. Why doesnt the US or other countries for that matter follow what the Candians are doing?
Read my plan to save the Bengals
...it could finally mean that there will be cool internet appliances all over the house.
/. whilst listening to geeks in space in full stereo, and all on our fridge doors.
As long as the people involved in the implementation of this don't ruin it by adding silly usage charges, then we will finally be able to read
So, who's for a game of quake? I'll see you by the microwave.
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Dallas-based start-up Media Fusion has won a U.S. patent on a process it says can send data, video and voice over electric wires at speeds thousands of times faster than current high-speed Internet access technologies."
:)
In other words it appears Media Fusion has patented an electronic signal on a metalic fibre called a wire. They must be so proud of their Intellectual Property
The UPS that will keep the internet connection live in the event of loss of electricity...
:) -Dan
This repeats a story from last week I think. The British trial was abandoned for turning street lights into antennas. This idea relies on magnetic effects. But no clues yet as to how good it really is.
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Infuriate left and right
It sounds wonderful until you start thinking about it. Communications all boils down to signal-to-noise ratio. The 60 Hz (50 Hz in Europe) power wave is no problem, but what about all the switching noise, corona discharge, insulation arcing, etc? Then you have to get past [around] transformers.
Also, over long transmission lines signal tends to get spread out (smeared) as the velocity-of-propagation varies. AFAIK, Power lines were not designed with any consideration of Vp.
Patents do NOT impress me.
-- Robert
I know many of you are saying how this has been tested, and it failed. In the related story over the weekend, posters were talking about the transformer issues and things of that nature.
Did anyone read the linked story from the weekend?
This is not about sending an electric signal over power lines. This is about manipulating the magnetic field which forms naturaly around a wire when you send an A/C current through it.
This is new. This is exciting.
Here in the UK also.
I'm not so sure that the infrastructure is already there. Even if you get 1 terabit on a single segment of wire you then have to share that across all users on a CSMA/CD domain this could be 000s of users. On a CSMA/CD domain you also tend to only get around 30% of the available bandwidth, because of multiple user packet collisions.
You will also have to have effective "routers" and a backbone connection to distribute the data to the network proper.
As I see it there are quite a few changes to infrastructure required. The cable people didn't seem to have much probalem installing cable across the country and it is better suited than using existing old cables that might not be quite up to scratch. I'm sure there will be loads of incompatibilities with certain surge protection devices etc.. etc..
Here in the UK their are health and saftey rules preventing power and data cables being put in the same coduit. I wonder if this would pose a problem for this kind of technology.
If Media Fusion's technology does work, it could radically shake the telecommunications market. Telephone and cable companies have invested billions of dollars to ready their networks for high-speed data transmissions.
That's a slight understatement. If the technology *does* work, look to see major U.S. Telecommunications companies go screaming to the FCC, demanding the regulation and taxation of the service in the same manner that their lines are. If that doesn't work, I'm not sure what they're going to do, because a technology like this could threaten to put them out of business.
How practical is it? Does anyone have more detailed information (perhaps information of a more technical nature) about how they're doing it? Is this just a vaporware announcement intended to scare the telcos?
While the details of actual implementation are vague, if it works, this may present yet another solution to the 'last mile' problem, which I personally see as the last major bottleneck before the true dawning of the (drumroll please) information age. Between this type of easy access to high speed broadband with existing infrastructure, and the high speed wireless stuff we read about a couple weeks ago, we might just get things *properly* wired sometime soon
Anthony
"I think any time you expose vulnerabilities it's a good thing." -Attorney General Janet Reno
OK, I love the hype about connecting to the "internet" at blazing fast speeds ... especially since eventually all of these connections must go into telecommunications circuits that tie into a tier 1 isp and to the Internet backbone, utilizing private and public interexchanges, and the rest of the resources that we all share right now.
Access technology is worthless without the backbone to back it up, and right now the MAEs and other interexchanges, along w/ private peers and international cables, are our bottleneck points. You can't jam a gigabit pipe into a T1 and expect any performance.
good. fast. cheap. (pick any two, you can't have all three)
Now if there was only a way to get this kind of speed with no wires at all!
I dream of an inexpensive, wireless gigabit/sec connection!
Well, afaik some of the most high-end wireless consumer networks available at this time would be Hiperlan (23.5Mbps). Some information is available
here and here.
There exists faster wireless networks, however then we're not in the "consumer end" any more.
-- "Life is a bitch - and she hates me..."
Are we going to open up a discussion thread everytime somebody mutters "Power Lines" and "Modem" in the same sentence? This is twice in the last couple of weeks, and no new information has come to light beyond a process patent.
I mean, really.
A valid point was also raised about cost for this sort of service. When living in Canada, I paid CND40 for 24/7 CableModem service. Currently, in Ireland, I pay about IRP100 per month for heavy useage over a standard modem. This is because Eircom (formerly Telecom Eireann) was only recently privatised, and there is still little enough local competition. I believe there are a grand total of 20 cable modems in Dublin, all currently being tested (In Terenure, if any Dubs are reading.) At any rate (pun!), isn't there a threat regarding cost in the States? I'm not certain, but I thought the power grid was government property, and I can imagine how much they would enjoy the added revenue provided by fixed-cost high speed internet service. And I don't see an independent startup laying power lines in order to compete, personally.
This seems like little more than a pipe dream (pun!), particularly for those already enjoying the wonder of Cable Modems and DSL links. If anything, this new tech -- if it ever becomes new tech -- will up your prices and knock your smaller providers out of the market.
-l
However, this is not a new idea. The transmission of electronic data over an electrical power line was first put forward in the mid 1940's, according to Wireless World. The idea was vetoed, at the time, because it was believed that this would allow a dictator absolute power over information. It was deemed essential that wireless methods of communication were predominant.
In this age of paranoia, suspicion and Government surveilance, I find it fascinating that cable-based communication is actually MORE popular than when the risks were merely speculative.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Don't knock Canadians.. I will assume from your email address that you are British, so I would also care to remind you that Britian is FAR behind Canada in many aspects of "high-speed technology". I remember when i was still in jr. high (around 10 years ago) they were building fiber optic telelphone lines that spanned a huge chunk of our nation.. As I recall, that never happened in England until years later, if it has yet at all. :) Excuse any rudeness in this note as I'm sure you can understand: I feel angered by some cheap pot-shot at my country by an misinformed, ignorant troglodyte. Canadians excell at MANY other things that just hockey, bub, and taking some cheap potshot at one of the World's quieter and more humble nations isn't cool.
I dont want to see another article on this unless it says "taking signups in your area now"
Go read the article, I'm trolling in the least. It's fucking ubelievable.
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We cannot reason ourselves out of our basic irrationality. All we can do is learn the art of being irrational in a reasonable way.
I looked at the patent ffrom the IBM patent server. As a physicist, I can say that most of the contents are mumbo-jumbo.
It is important to remember that for a patent to be valid, it must be detailed enough for one 'skilled in the art' (patent office terminology) to build the device based on the patent (i.e. it must be enabling). A patent (the word, of course, means open) is supposed to open up a technology... you can't simultaneously have something under wraps and patented. You either have a trade secret or a patent, not both!
I would consider myself to be reasonably skilled in the arts associated with this type of work (PhD in Physics, Caltech, 1983) but the patent is certainly not enabling.
Worse, I suspect that it isn't based on any real physics. The discussion of exciting atomic states in the magnetic fields surrounding a wire reads a lot like the kind of language one sees in perpetual-motion patents to try to cover up the complete lack of any real possibility of success.
If I were making investment advice, I would certainly not recommend buying into this one.
>They convert the power to high voltage DC for the Intertie and use great big inverters at the destination. DC doesn't have losses.)
Seems backwards to me... Edison always wanted DC for power distribution, but AC wond out because it is far less lossy. For a really long wire (i.e. power distribution line), the DC resistance is *way* higher than the AC impedance. The electrons have to travel from point A to point B for DC (let say 1000km for this example), while at 60 Hz, the electrons bounce back and forth, going far less distance and losing less of their potential energy (read: voltage) along the way.
I haven't heard about the Pacific Intertie, but hey, they could be doing this... though I somehow doubt it.
Just my $.0004^.5
"It's tough to be bilingual when you get hit in the head."
Just a quick followup - web info says it's a 500kv AC line...
"It's tough to be bilingual when you get hit in the head."
. The cable techs haven't changed much in the past 10 years, but the technology they are dealing with is barely in the grasp of most engineers.
Absolutely, the cable tech who came to my house to connect my cable modem was pretty clueless about how the whole thing worked, I got the impression that he'd basically gone to a couple of workshops the company (TCI now AT&T) put together. He really couldn't answer any of my questions about how it worked, and he didn't know what a cross-over cat 5 cable was.
I finally told him to run a cat 5 line to X point, plug in his laptop, let me make sure it works, then to leave and I'd take it from there. So he did that, I loaded Slashdot on his laptop (I was pretty sure this guy wouldn't have it cached) and sent him on his merry way. I set up my hub and ran some lines to my roomies' computers and was surfing half an hour later.
My point? This guy couldn't hook two computers to each other if he had to, he was a guy who knew how to hook up coax connections, and they gave him a laptop and taught him how to plug cat5 connections together. How hard would it be to get some people (college students?) with a basic understanding of networking?
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When in danger or in doubt, run in circles, scream and shout. --Robert A. Heinlein
Don't forget those of us with UPS systems. The one under my desk at home doubles nicely as a foot-warmer as well. I keep a second one in the basement keeping the hub, cable modem, and NAT box up and running too, I can keep using the net for a good 15 minutes without power.
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When in danger or in doubt, run in circles, scream and shout. --Robert A. Heinlein
Of course it was around the the conductor - all electronic signals are transmitted as changes in the magnetic/electric fields around a conductor - thats basic physics.....
Um, no.
Signals in most circuits are trasmitted as a flow of current _within_ wires, driven by an electric field gradient _within_ the wires (called "voltage"). Electric fields outside the wires try to move current between the wire and anything nearby, but this is an unwanted side effect, stopped by something called "insulation". However, the electric fields also result in capacitive coupling between nearby wires, which causes something called "capacitive cross-talk". This is minimized by keeping wires far apart and minimizing the amount of parallel surface area of conducting regions.
As a side effect of the current flow, a magnetic field is set up both around and within the wires. The current flowing within the wire and the magnetic fields around the wire are intimately connected; you can't have one without the other, and they interact very strongly with each other. You can't "transmit information in magnetic fields around the wire" without interacting with currents in the wire too - the magnetic field is _caused_ by local currents in the wire. In most systems, magnetic fields are an unwanted side effect. As there is mutual inductance between any two wires in a circuit, the magnetic fields caused by current in one wire will set up currents in other wires. This is called "inductive cross-talk". It is severe only for wires that are very close to each other, or that have a particularly vulnerable geometry.
For an excellent book on the basic physics involved, I recommend "Fundamentals of Physics, Fifth Edition", by Halliday, Resnick, and Walker. Another good reference is "Physics for Scientists and Engineers, Extended Version" by Tipler.
This is bogus.
Electromagnetic fields do not interact with each other. They couple with charged particles, which couple back to the field. A "magnetic field" wouldn't be acting as the waveguide - the wire would. Over a single wire with no interference, this would work quite well. However, the actual power grid does not meet this specification.
This will not work all the way down to your socket but powerlines hanging from pylons could be used by utilities to compete with fiber.
The problems with this include, but are not limited to:
Power networks were not designed with eliminating reflections in mind, and were not designed for noise rejection. Cable - which is shielded coaxial cable - _is_ designed for both of these, and so has much higher ultimate bandwidth limits. It too behaves like a waveguide at high enough frequencies, and it's shielded. Optical fiber can beat both hands-down - it's a waveguide for an EM signal with a frequency _many_ orders of magnitude higher than radio and microwave signals.
Summary: Bandwidth limits and signal quality problems make this a not-very-useful technology.
Of course, Britain is notoriously strict about
broadcast regulation. Isn't that the place where
every TV must be licensed, and there are actually
spooks who spy on people looking for unlicensed
TV's?
Maybe "turning street lights into antennas" is
something America would tend to tolerate.
We tolerate the sulfur lamps in the damned things,
after all. We'll even tolerate wasting millions of acres of woods for the poles.
-fb Everything not expressly forbidden is now mandatory.
Did you even bother to read any of the articles? The patent is for technology which transmits data through the magnetic fields surrounding power lines, NOT through the power line itself.
I'm afraid that this is a meaningless statement, most likely invented by their marketing departments. Click on "User Info" above to see my previous posts which cover this in more detail.
Signals capable of transmitting data in GBits/sec range shall be radio in GHz range or even optics. Electricity is an electro-magnetic phenomean and therefore manipulating the magnetic field interferes with the current in the conducter. And as explained many times before; high frequency signals cannot pass through transformers that by nature function as low-pass filters.
When using even higher frequency-signals (even up to optical signals) there would be problems with the variation of the dielectric constants of material surrounding the wires. Some use platic insulators, some paper/oil, some use air, etcetera. These changes would diffuse or reflect signals. And once again it wouldn't pass the transformer.
What do they claim:
They claim they can use the electric utility-network to transmit signals in GBit/sec range over thousands of miles. (OK, this could be done by using the network as antenna and sending very powerfull radio-signals of several kW. Only one transmittor per continent: not very useful).
They claim to use the magnetic field, not the conductor. First ask yourself: what would happen when we have no current? No signal? (this happens 50 times per second, in USA 60 times). Why they claim this: because it is different and can even confuse the average EE that think in currents instead of magnetic fields.
They claim to have patents. Well, I'm not impressed. In USA even perpetual mobiles can be patented (see www.entropysystems.com).
They claim they will demonstrate their system somewhere in 2000 by sending HDTV-signals over thousands of miles of electricity-network. This will be done to find enough investors to make the 300 million dollars they need 'to speed up the development'.
Now I understand, poor investors.
-- Fur is worn by beautiful animals and ugly people
My EE prof worked as a researcher for Southern California Edison for 20 years and he said that the reason they used DC for that power link was to avoid phase synchronization problems.
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"L'IT c'est moi!"