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Chinese Professor Builds Li-Fi System With Retail Parts
alphadogg writes "The equipment is big and expensive, with the research costs at almost $500,000. But by just using retail components, Chinese professor Chi Nan has built her own Li-Fi wireless system that can use LED lights to send and receive Internet data. "I bought the lights from Taobao," she said, referring to the Chinese e-commerce site. The professor from Fudan University showed off the technology on Tuesday at the China International Industry Fair in Shanghai. Unlike traditional Wi-Fi routers that use radio signals, Chi's system relies on light to send and receive data wirelessly. Others scientists, especially in the U.K., have also been researching the technology, and dubbed it "Li-Fi". But rather than develop specialized hardware, Chi bought off-the-shelf retail parts to create her system."
Can someone tell me what all the fuss about "LiFi" is? We've had free space optical networking for decades. It's not new and it's not a good general networking solution, especially for household use, which the LiFi buzz seems to be implying.
I just don't see a broad use case for this and I don't understand why it is getting so much press. Will they, next week, "discover" that they can make it work in the dark by using infrared TV remote controls?
P.S. As someone who is jumping through hoops and going to great lengths to eliminate flicker in household LED bulbs, the thought of intentionally flickering the light, even at high frequencies, does not sit well with me.
I would bet that it's more tuned to commercial markets. For density in classrooms it's not uncommon to place two WAPs in one room for the express purposes of serving the 30+ devices in that room, and with the bleed-over between rooms all of the WAPs have to step-down their power to avoid interfering with each other.
A wireless medium that doesn't use something capable of penetrating through walls would actually be an advantage in these kinds of environments. Granted, to be practical it would require peoples' devices to have both WIFI and LIFI, but they often have both WIFI and copper capability now anyway, so more than one interface isn't a stretch.
Do not look into laser with remaining eye.
You're thinking of Japan... pornography is illegal in China, and tentacles aren't a part of their culture to begin with. Also, the "Chinaman" you speak of is a woman.
Nothing really. It's a new buzzword that everyone is oogling. we were getting 4mbps over IR point to point using PVC and some lenses to steal internet from the college back in the early 90's. One of the buildings was visible from our rental so we ran wires and had an old linux PC at each end using the DB15 ports on the old ethernet cards we found and set up a photodiode and an IR led on each end to set up an optical link. WE actually used visible LED's to start with to set everything up, and then went IR for stealth.
Worked great we had the fastest internet around for a house with 12 random nerds in it. I will bet that the transmitter portion is still on the roof of that school building 20 some years later.
Do not look at laser with remaining good eye.
News just in: IrDA wants its acronym back. On a more serious note, I really did like IrDA. It was slow as crap and the range sucked, but at one point in time, pretty much EVERYTHING had IrDA support. Laptops, cell phones, PDAs, HPCs, etc. You could buy serial dongles to add to any PC for $5 or so. It was the go-to fallback to transfer a file or data between two devices that had disparate storage card types (PC-Card vs CF cards, etc), or you didn't have cables to connect them up directly. Bluetooth has sort of replaced it, but you can't just bit-bang communication with a bluetooth device using a microcontroller and two 25 cent components. Plus Bluetooth has been implemented by OEMs as more of a method to connect dumb peripherals than a method of communicating directly between devices.
Better known as 318230.
Most homes in Chinese cities are in buildings like condominiums. Only the walls are poured concrete. That's because the walls are load-bearing as part of the design. At least that's my understanding. Regardless, getting WiFi access several rooms away can be real difficult if not impossible.
If you're part if the growing middle class that plans on expanding network connectivity in the home, you really need CAT5e installed (outside the walls unfortunately).
Life is not for the lazy.
Chinese Professor Builds Li-Fi System With Retail Parts...
...which isn't as good as pro kit.
The equipment is big and expensive, with the research costs at almost $500,000.
Research costs don't tell you anything about the cost of "the equipment," whatever that refers to. A modern mobile phone might set you back $200, but you could easily make the research costs total several billion dollars depending how far you want to go back. If someone comes along with a couple of tin cans and a piece of string, I don't really see how that's automatically newsworthy.
But by just using retail components, Chinese professor Chi Nan has built her own Li-Fi wireless system that can use LED lights to send and receive Internet data.
There are plenty of things I can do with retail components that wouldn't be possible without prior billions being spent on research. That doesn't make me the King of Awesome (I am, but it's entirely unrelated).
FWIW, Chi's system works over about 3m, the hardware is large and heavy, and it achieves a speed of about 150mbps.
systemd is Roko's Basilisk.