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1Gbps Optical Wireless Network Might Replace Wi-Fi
Mark.JUK writes "Pennsylvania State University has developed a new method of indoor Optical Wireless network that does not require a line-of-sight and runs at speeds of 1Gbps+. The system uses a high-powered laser diode — a device that converts electricity into light — as the optical transmitter and an avalanche photo diode — a device that converts light to electricity — as the receiver. The light bounces off the walls and is picked up by the receiver. Traditional radio frequency systems (Wi-Fi , WiMAX etc.) do not require line of sight transmission, but can pass through some substances and so present a security problem. Light, in a room without windows, will not escape the room, improving security."
it's interrupting my downloads!
sigs... don't talk to me about sigs....
This is only going to work in the small area that the laser can get to, so cables might be a better solution.
I like to shut the door of my room while watching my movies and other stuff.
In soviet russia the government regulates the companies.
If the LASER is anywhere in the visual spectrum, the whole house could become a perpetual disco ;)
> Light, in a room without windows, will not escape the room, improving security.
Although at a cost? This system might be useful for Universities that need to provide wireless to a hundred computers in the same room, but it would be almost useless for homes and such, where one of the big reasons to go wireless is to avoid the need to rewire the house. To use a 1 Gbps signal, you'd need a hard-line to the room.
The other point is that for most applications, it's simply unnecessary to improve over the speed of modern wireless.
Still, there are a few niches where this would be useful, and it sounds like a really fun idea to develop.
-- IANAL, this isn't legal advice, and definitely isn't legal advice for you. Also, Squee!
How many homes don't have windows? Of those homes, how often is it that there is a need to connect with a computer inside a closed room? Any system that can connect to a computer inside a closed room can also be connected to from outside the house. Any system that can't be connected to from outside the house also can not connect to a system with the door shut. The number of times the signal can bounce off walls would significantly affect the range of the system. So while a direct path between floors of a house may be 10 meters, the path through the house from the top floor going around everything that is opaque to the system might be 50-60 meters and quite possibly out of range.
Sigs are too short to say anything truly profound so read the above post instead.
Light, in a room without windows, will not escape the room, improving security.
As usual, Windows makes networking less secure, why am I not surprised.
XML is like violence. If it doesn't solve the problem, use more.
Well duh, everyone knows that avoiding Windows improves your security.
The other point is that for most applications, it's simply unnecessary to improve over the speed of modern wireless.
Uh huh, and 640K should be enough for anyone, and there's no reason to go to broadband when a regular old analog modem is sufficient for most applications, and...well you probably get my point by now.
IR office networks were popular around 15 years ago. HP used to have a "NetBeame" IR access point product line. (There's one on eBay for $49.) There's Linux support for IRNet. The Infrared Data Association is already promoting gigabit IrDA.
The concept of diffuse IR networking works fine, but it never really caught on. You can usually get a signal with one bounce, typically off the ceiling, but more than one bounce and it tends not to work. You don't get any useful diffraction around obstacles at IR frequencies, so shadows are a problem. If you populate the ceiling with little IR domes, it works fine, and I've seen that done, but it's obsolete technology now.
users won't tolerate very intermittent connections, and won't tolerate having to aim their system at all. I remember using irda brirefly, and it was very touchy.
Wifi is generally omnidirectional. light doesn't work that way - you can get a very strong signal 20 feet from it, or a nonexistent signal six inches away, if you're in a bad spot. And this effect occurs in both directions, and has different deadzones. So not only are you having a problem receiving, you're also having a differnt problem sending, requiring a great deal more adjustment to get communications going. Having to solve two positional problems simultaneously effectively quadruples the difficulty of the task.
It's also going to be a great deal more environmentally sensitive. You can drop a bar or two if someone sets their laptop bag down beside your laptop and clouds direct line between you and the access point. Imagine how much worse that can get with light, and at a greater distance - you won't just lose a bar or two, you're almost certain to get completely disconnected. A couple chatting as they walk down the hall ten feet from you could ground you for several seconds, giving you absolutely no hint of what caused it.
No, this technology's not going anywhere. Sure it works, but it's nowhere near as reliable as the public will demand. Look how badly people flip out now over an occasional dropped call.
I work for the Department of Redundancy Department.
...a friend of mine runs into the room in the middle of a download and starts playing with a flashlight?
"I'd just like to emphasise that taking a million years isn't a metaphor here..." -Rich Bradshaw
since when can't lasers pass through walls!? :) Use a BIGGER lazer!
great - so now millions of drones will have to sit in windowless rooms so the network wont leak out... and the air and the trees and the birds cant leak in... dismal existence... borg colony bleah! :-P
what if you open the door? Will internet leak out of the room?
I suppose a double door or, more entertainingly, a revolving door, could help with this...
Have a look at this. We're intercepting an electromagnetic signal in the terahertz range and it seem to have some kind of beating. I think we just might have found a pulsar!
Swedish plasma phys. PhD student; MSc EE; knows maths, programming, electronics; finance interest; seeks opportunities
Do not check network signal with remaining eye.
Proud member of the Weirdo-American community.
If I ignore the encoding issues and assume some mix of frequency and amplitude shifts or whatever to get that kind of bandwidth, I can go along with the idea that a well placed optical transmitter could bounce light around the room enough to do this -- but what about the return signal from the workstation or device? That would hardly be placed in an optimal location.
Further, consider that wireless is most useful for mobile and transient devices -- laptops, sure; but what about cell phones, pda's, sensors, and all manner of other wireless things. These are frequently -- even usually -- not placed in direct visual sight.
Frankly, I see this technology as potentially useful in long distance settings between stationary platforms (particularly in space) but not so much for day to day campus or home-office use.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
It's a laser so the beam can be tight. That lends itself to geeking it to reflective targets mutually visible in outdoor applications. If people can get wifi at 237 miles, this tech may be capable of extending both the range and bandwidth of point to point communications. That would extend the reach of the Internet to a lot of people isolated by distance and infrastructure. That would be cool.
And then there's the neighborhood network thing. I can gather maybe 250 single family homes into a network with a fenceline network without crossing a right-of-way with a cable. Leveraging this tech I could probably extend that reach to 30,000 families. If you can build a 1 Gbps network that large in the US, the Internet will beat a path to you because you've got something they want: earners with eyeballs. Real bandwidth becomes free, which changes a whole bunch of things in a totally positive way
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