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> It’s a spot no human has ever explored, and it’s so deep that any communications from the submarine will take seven seconds to travel back up. I found this i
by sfifs 8y ago
> It’s a spot no human has ever explored, and it’s so deep that any communications from the submarine will take seven seconds to travel back up.
I found this interesting. Are they going to use sound waves for communication? Aren't there any electromagnetic wave based communication mechanisms that work in the ocean or does the depth of water absorb all emails?
- ahje 8y agoI'd guess they use either aucustic communications with some encoding sheme[0], or some kind of VLF communication system with very low bit-rates. [0]: https://en.wikipedia.org/wiki/Underwater_acoustic_communication https://en.wikipedia.org/wiki/Underwater_acoustic_communicat...
- lb1lf 8y agoThe depth a RF signal reliably penetrates to in water is proportional to its wavelength. Hence the ELF sites used to communicate with submarines - we're talking EM radiation at a frequency of a few tens of hertz. These transmitter sites are huge - not to mention the power requirements, which is easily in the MW range - so they could only be used to communicate from shore to submersible. Return comms would have to be by acoustic means, due to size and power constraints in the submersible. Also, the bandwidth of ELF systems is very low - think several seconds, if not minutes per bit - the bandwidth of an acoustic system is orders of magnitude higher. Edit: I had bungled the first paragraph. My apologies.