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One of the main advantages of Li-Fi over Wi-Fi that is often stated in journals is that Li-Fi works underwater while Wi-Fi does not. But the frequency of visible light is much higher than the frequency of radio waves used by Wi-Fi, so by the skin depth equation shouldn't visible light be attenuated more than radio waves.

Is there something I'm missing or are these journals misleading?

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    $\begingroup$ Water is opaque to radio waves but not to visible light, especially the higher frequencies of visible light. Blue or green light can be used to send a signal as far as 100 m in clear water. $\endgroup$ – Ben51 Oct 5 '18 at 2:06
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I think the statement seems to be something along the lines of: Wi-Fi does not work at all underwater but Li-Fi can work underwater.

I found this article on Li-Fi which references Wikipedia. http://www.ijstr.org/final-print/oct2014/Li-fi-A-New-Era-Of-Wireless-Communication-Data-Sharing.pdf

The wiki article says:

Since light can travel through water, Li-Fi based communications could offer much greater mobility.[46] Li-Fi's utility is limited by the distance light can penetrate water. Significant amounts of light do not penetrate further than 200 meters. Past 1000 meters, no light penetrates.[47]

It appears that the utility of Li-Fi is in comparison to cabled communication and Wi-Fi underwater. In this case up to 200m wireless communication may be an advantage.

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  • $\begingroup$ man... that journal needs to hire copy editors. $\endgroup$ – ZeroTheHero Oct 5 '18 at 2:21

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