A new strategy for sending acoustic waves through water could potentially open up the world of high-speed communications activities underwater, including scuba diving, remote ocean monitoring, and deep-sea exploration.
By taking advantage of the dynamic rotation generated as acoustic waves travel, the orbital angular momenta, researchers at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) were able to pack more channels onto a single frequency, effectively increasing the amount of information capable of being transmitted.
They demonstrated this by encoding in binary form the letters that make up the word "Berkeley," and transmitting the information along an acoustic signal that would normally carry less data. They describe their findings in a study published this week in the Proceedings of the National Academy of Sciences.
[...] While human activity below the surface of the sea increases, the ability to communicate underwater has not kept pace, limited in large part by physics. Microwaves are quickly absorbed in water, so transmissions cannot get far. Optical communication is no better since light gets scattered by underwater microparticles when traveling over long distances.
Low frequency acoustics is the option that remains for long-range underwater communication. Applications for sonar abound, including navigation, seafloor mapping, fishing, offshore oil surveying, and vessel detection.
However, the tradeoff with acoustic communication, particularly with distances of 200 meters or more, is that the available bandwidth is limited to a frequency range within 20 kilohertz. Frequency that low limits the rate of data transmission to tens of kilobits per second, a speed that harkens back to the days of dialup internet connections and 56-kilobit-per-second modems, the researchers said.
Transmitting data acoustically could tip off the dolphins and whales to our plans...
(Score: 1) by anubi on Wednesday June 28 2017, @06:31AM (4 children)
I keep hearing more and more about entangled quantum communications.
Assuming this is not electromagnetic, does this work underwater as well?
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 0) by Anonymous Coward on Wednesday June 28 2017, @06:50AM (3 children)
Yes entanglement works underwater, but there's a risk of tearing a hole in the fabric of spacetime and draining all of Earth's oceans into voidspace. The good news is the risk is zero except under certain circumstances. Don't tell the terrorist towelheads that all they would need to do to destroy the Earth would be to jam a wet towel into the transmitter.
(Score: 0) by Anonymous Coward on Wednesday June 28 2017, @07:18AM (2 children)
If you ask me, those "towelheads" have done a damned good job getting the whole world worked up over all sorts of fear and security theater - like a wasp in a school bus full of kids.
(Score: 0) by Anonymous Coward on Wednesday June 28 2017, @09:34AM (1 child)
That's just that one scaredy fat kid, the one who ran away in 1956? But he's back on the bus, towards the back, and it is a short bus, not because of placement or anything but just population density, but that does indicate a particular cultural isolation, and he's scared shitless of Mooselins. More than other ungulates, and too an irrational degree. We have requested professional assistance.
(Score: 0) by Anonymous Coward on Wednesday June 28 2017, @10:31AM
I wasn't aware Trump ran away in '56.
... You're surely speaking of Trump, aren't you? 'Cause he's the one person who's scare has the highest impact: extra congestion at the Supreme Court, terawatts-hours wasted on TV, half US population becoming hysteric and the other half angry, extra CO2 emitted by human respiration in a non-productive and non-recreational way.
(Score: 2) by c0lo on Wednesday June 28 2017, @11:23AM (1 child)
Better at deep sea then in the middle of nowhere on the land, at least you'll be able to tweet.
(grin)
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by bob_super on Wednesday June 28 2017, @05:56PM
If you start tweeting while we're diving, I will have to tell the coast guard that the Great White who took you went swimming that way sir, yes sir, that way for sure, not where the corals that were bleached yesterday have recovered a nice crimson color and someone disturbed the rocks and the sand, no sir, that mean mean Great White totally went the other way, and if someone finds the shark can they return the knife I valiantly but fruitlessly used to try to save you, I really liked that knife, nice and sharp, could cut through hoses and flesh like warm butter, sir, a good knife, that the mean mean shark took away when it surprised the silly tweeting man, that way, not where the other predators and bottom feeders are now gathering, sir, that other way down there...
(Score: 4, Insightful) by davester666 on Wednesday June 28 2017, @07:10PM (3 children)
Or is it one of those "who the fuck cares?" things.
(Score: 2, Interesting) by dw861 on Thursday June 29 2017, @04:58AM (2 children)
I was pretty surprised by how uncritical this post was (though have not followed it through to the originals).
For anybody interested in the horrible effects of human-generated undersea sounds on non-humans, I recommend getting ahold of "Sonic Sea".
The full film is about an hour, but here is a short trailer from Youtube:
https://www.youtube.com/watch?v=T-jabL64UZE/ [youtube.com]
Like any film it can be criticized, but it is a good introduction to the problem if you haven't thought about the issue before.
(Score: 1) by dw861 on Thursday June 29 2017, @05:01AM
Sorry, just to clarify, by "this post" I meant the original story, not the post to which I responded. I suspect I am in agreement with davester666.
(Score: 3, Interesting) by JNCF on Thursday June 29 2017, @07:42PM
I was reminded of The Persistence of Memory [youtube.com], in which Sagan argues for the potential of a global communications network of whales stretching back millions of years that was only recently disrupted by human noise. The suggestion of songs changing by consensus is especially interesting; I would totally buy whalecoins that were mined using a Proof Of Whale algorithm.
(Score: 3, Funny) by jasassin on Thursday June 29 2017, @09:48PM
Now the Legion of Doom can watch 4K Netflix without surfacing!
jasassin@gmail.com GPG Key ID: 0xE6462C68A9A3DB5A