Li-Fi instead of Wi-Fi

I am just curious with this product, has anyone use Li-Fi device here? in replacement to Wi-Fi? (question corrected)

calmoptic43 said:

I am just curious with this product, has anyone use Li-Fi device here? short for Light Fidelity, in replacement to Wi-Fi?

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The Fi in Wifi does not stand for fidelity. It doesn't stand for anything actually. Wifi is just a name.

You use LiFi everytime you use an Infrared remote ;-)

There used to be headphones that used IR light to transmit audio from a source. I always thought it was an appealing idea, but never used it. I still think it might be a fun idea for a home project and a good excuse to play with phase-lock-loops to FM modulate IR light with audio.

The downside of using light is fairly obvious... you need either a clear line of sight between the transmitter and receiver, or a path that you can reflect the light off of (and have enough spare transmitter power to accept all of the losses due to scattering light at the reflected surfaces).

The use of light to transmit information through the air is commonly referred to as "free space optics". You can find stuff on the web about people sending info over distances of many kilometers or miles. The varying density of the air does make the light diverge in unexpected directions though, making it not very effective for long distances. The advances in adaptive optics might compensate for this, though.

Thanks for the correction

An extremely uninformed passing thought; wonder if there's a way of modulating your household light circuit that didn't have a visible effect, but could enable you to "light-pipe" your music anywhere in the house :tinfoil::rock:

There's a thread on here somewhere where some guys on some islands used IR receivers to cloud bounce messages back and forth ~70 miles apart, was some time ago..

The "Li-Fi" wireless networking concept has been kicked around for years, typically pitched as some way to manage the problems associated with wi-fi. It's been the stuff of at least one TED talk and other breathless futurism.

What it doesn't seem to have produced yet are any good solutions to any particular problems. Wi-fi sees steady evolution of its basic capabilities through endless revisions to the baseline standard and some forks that add capacity in parallel. Some of the new hyper-local high-speed beamformed stuff will likely address some of the other challenges when it comes to reducing collisions and reducing the reach for security.

I expect one of the IrDA standards to see a revival before Li-Fi takes off - they have protocol stacks and some history making working products. IR spectrum also likely not as busy as the visible spectrum.

Perhaps, there would be a great chance of possibility in the future that flashlight can be use to transmit data similar to wifi..

calmoptic43 said:

Perhaps, there would be a great chance of possibility in the future that flashlight can be use to transmit data similar to wifi..

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Like fiber optics without the fibers

calmoptic43 said:

Perhaps, there would be a great chance of possibility in the future that flashlight can be use to transmit data similar to wifi..

Click to expand...

there's no reason that it couldn't be done. It's more a question of the practical aspects.

for instance, the lab I work in uses fiber optic converters for ethernet interfaces. This shows that ethernet can be sent over an optical path.

I used to work on a project that was exploring how to use laser to communicate between satellites. There were a variety of technical hurdles at the time, including the difficulty of getting a sufficiently high power laser to fling enough photons across thousands of miles and into a receiving telescope to be useful. Getting the transmitting and receiving telescopes pointed at each other is not trivial either. At least there was no annoying atmosphere to deal with.