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800Mbps Wireless Network Made With LED Light Bulbs
Mark.JUK writes "German scientists working at Berlin's Fraunhofer Institute for Telecommunications have set a new world record for Visible Light Communication technology after they succeeded in using regular red, blue, green and white LED light bulbs as the basis for building a new 800Mbps capable ultrafast Wireless Local Area Network. Dr. Anagnostis Paraskevopoulos explained: 'With the aid of a special component, the modulator, we turn the LEDs off and on in very rapid succession and transfer the information as ones and zeros. The modulation of the light is imperceptible to the human eye. A simple photo diode on the laptop acts as a receiver. The diode catches the light, electronics decode the information and translate it into electrical impulses, meaning the language of the computer.'
The solution, which could be installed on ceilings and would cover approximately 10 square meters, would be ideal for HD video streaming and inside Hospitals or Aircraft where traditional Wi-Fi is often banned. However visible light signals can easily be blocked, such as when a hand is passed in front of the transmitter."
Seriously, does anyone here on Slashdot need their summary dumbed down that far?
WARNING! This girl exceeds the MAXIMUM SAFE standards established by the FDA for BRATTINESS
It could just as easily be seen as a security feature. Drawing the shades is easier than encasing your room in Faraday cage. And while I'm at it, since when do hospitals ban Wi-Fi? The ones I've been around (Tufts Medical Center, Children's Hospital Boston & St. Elizabeth's) have all offered it for patient and visitor use.
The storm has LED some to believe that it is one bit of a self-propelled message that is transferred over thousands of miles. While working on solar energy, transfer of this information goes on during the night, preventing the thread to be derailed by Slashdot's nuclear proponents.
There is currently discussion whether the storm is a one (as seen from the side) or a zero (seen from top).
Hey, I tried to keep bring it back on topic.
Bert
Eventually, someone will figure out an even more private method, like some kind of wire.
'With the aid of a special component, the modulator, we turn the LEDs off and on in very rapid succession and transfer the information as ones and zeros.
I bet they had something to read the modulator signals on the other side.. an Anti-Modulator perhaps?
They could come up with some cool acronym for this system.. MOAMO ? noo.. i'm sure there's something better..
----- The internet has given everyone the ability to have their voice heard equally as loud.. even if they shouldn't be
Its not a matter of feeling or not. Wi-fi has been proven to interfere with emergancy landing equipment. Don't believe me? Read for yourself. http://www.zdnet.com.au/wi-fi-proven-to-interfere-with-aircraft-339311113.htm http://www.flightglobal.com/articles/2011/03/10/354179/wi-fi-interference-with-honeywell-avionics-prompts-boeing.html
Not sure if you are trolling but, No, LEDs are not capable of receiving data or acting as inputs. In the summary they used the example of streaming video where of course the monitor doesn't need to send and data back. The summary said they use a simple photo diode to receive. Light Emitting Diodes and Photo Diodes are 2 separate distinct things.
TODO create witty sig.
LED's are frequently used as photo-detectors. They aren't wildly efficient, but they do work.
www.parallax.com/Portals/0/.../LEDLightEmitterandDetector7-31-07.pdf
It makes the optics so much simpler if you can use just one device for TX and RX.
How do I watch a movie in the dark then?
Most of us feel pretty strongly that WiFi on planes is not dangerous and that it should be allowed as-is. But since there are some extremely stubborn and inflexible people involved in policy making.
How many of you have done actual impact studies and considered things like out-of-spec transmitters, poorly repaired or perhaps modified wifi cards, etc?
Anecdotes are not data, but I had one particular laptop that, when the wifi was (inadvertently) turned on, prevented any PA announcements on one particular flight. And it was a bone-stock laptop with a bone-stock wifi card. After that discovery, the laptop was quickly retired, taken apart for the limited salvage value, and replaced with a new one.
It may well be that 200 properly functioning wifi transmitters all in close proximity of avionics will not interfere, but that presupposes that all 200 transmitters are working correctly, and for every single flight. It's easy to imagine a malfunctioning wifi card spewing power all over the spectrum, so presupposing that every card that will operate on every flight is correctly functioning is a losing supposition. My Ph.D. research included making recordings in electrically ultra-quiet environments and you would be surprised at the crap that even properly functioning equipment transmits.
It also may well be that 200 properly functioning wifi transmitters will interfere with reception of ground signals by overloading the input amplifiers on on-board radio receivers. Given what I know about radio receivers from my EE degrees, and my research experience, I'd put reasonable odds on that happening.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
"However visible light signals can easily be blocked, such as when a hand is passed in front of the transmitter."*
*depending on the power of the light, and the translucence of the object. Visible light signals cannot be easily blocked, for example, if they are emitted by say an 80-million candlepower searchlight. For example, this would not be stopped by a hand, nor eyelids. Such might prove to complicate use on-board an airplane in other ways, however.
-Styopa