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Dolphins' Hunting Technique Inspires New Radar Device

samzenpus posted about a year ago | from the flipper-power dept.

Science 79

minty3 writes "The twin inverted pulse radar (TWIPR) made by a team from the University of Southampton in England uses the same technique dolphins do to capture prey. Like dolphins, the device sends out two pulses in quick succession to cancel out background noise. The findings, published in the journal Proceedings of the Royal Society A: Mathematical and Physical Sciences, explained how the device resembles the way dolphins send out two pulses in quick succession to cancel out background noise."

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They mysteries and wonder (3, Interesting)

cold fjord (826450) | about a year ago | (#45219885)

They mysteries and wonder of creation still have many secrets to reveal and lessons to instruct the attentive.

Re:They mysteries and wonder (2)

cold fjord (826450) | about a year ago | (#45219899)

Hmmm, looks like I need to find a spelling bee. ;D

Re:They mysteries and wonder (1)

jamesh (87723) | about a year ago | (#45220429)

Hmmm, looks like I need to find a spelling bee. ;D

A babel fish should be able to sort it out so we hear what you mean not what you wrote :)

Re:They mysteries and wonder (1)

fahrbot-bot (874524) | about a year ago | (#45225303)

A babel fish should be able to sort it out ... :-)

I prefer translator microbes [wikia.com] ... :-)

Re:They mysteries and wonder (0)

Anonymous Coward | about a year ago | (#45224253)

No, I think you get a spelling C- rather than a spelling B.

Re:The mysteries and wonders (1)

MRe_nl (306212) | about a year ago | (#45219977)

"The mysteries and wonders of creation still have many secrets to reveal and lessons to instruct the attentive, as we slowly but inexorably destroy them".

Doppler Sonar, hurray! Best weaponize it asap.

http://suite101.com/a/ocean-pollution-a326713 [suite101.com]

Summary incorrect based on article (5, Interesting)

Jmc23 (2353706) | about a year ago | (#45219891)

The researcher did not actually investigate what it is that dolphins do, he thought of what they could possibly do.

I would be more interested in finding out if this is actually the technique dolphins use or do they do something different?

a 50 year old technique (4, Informative)

goombah99 (560566) | about a year ago | (#45220341)

I used to do something similar with unterminated co-ax cables for baseline subtraction. A box car integrator is short pulsewidth sampler. If one's baseline is large and fluctuating the traditional and expensive way to remove this is double pulse correlated subtraction. Which is nothing more that sampling things twice in succession and subtracting. Unfortunately that's not only expensive in terms of fast rececovery integrator hardware, but if you do it digitally it's got a small difference of large numbers problem as well. The clever way to do this is you don't terminate the coax on the integrator but rather extend the coax past it for a few feet, then leave it unterminated. The pulses thus fly past the integrator which can sample as usual, then 6 nanoseconds later an inverted reflection off the unterminated end pass the sampler in the opposite direction. Anything with fluctuation slower than 6 nanoseconds cancels out before the integrator can make the measurement. It's perfect and costs nothing. You dial in the timing with the coax length which is roughly a foot for every 2 nanoseconds.

Here they are doing this relying on the rephasing from the impedance mismatch of the reflecting object types being different. People who do FM lidar do something similar. It's an old old technique. probably dates back to the invention of coax.

Re:a 50 year old technique (0)

Anonymous Coward | about a year ago | (#45220499)

Incredible! Thanks for the insight.

Re:a 50 year old technique (1)

pspahn (1175617) | about a year ago | (#45220897)

Where is +1, Hall of Fame?

There are also other ways to do some of this. (4, Interesting)

Ungrounded Lightning (62228) | about a year ago | (#45220393)

One of the things described was comparing returns from a positive and a negative pulse, to detect the presence of rectification. Good idea, but...

There is another way to do that, which I believe is much more sensitive: Send the pulse on one frequency, listen for the return on a harmonic. Only nonlinear devices (mainly semiconductor junctions - constructed or accidental, like corroded metal joints) will produce the harmonic reflection.

This is how the "bury diodes in the drywall" bug works. The diode(s) sends a strong second harmonic reflection, essentially nothing else does. When the wall moves slightly, due to ambient sound it, varies the length of the transmitter-diode-receiver path, phase modulating the harmonic signal with the audio signal.

Because only change in phase matters, many diodes in the wall don't interfere with each other, but combine their randomly-phased reflections to make the wall more reflective (just like OFDM reception improving when you have multipath "interference").

"Illluminate" the building with a stable microwave carrier and listen to the second harmonic (shifted down) with an FM receiver - recovering the sound from the room adjacent to the diode-doped wall. Nothing to it.

Re:There are also other ways to do some of this. (0)

Anonymous Coward | about a year ago | (#45221783)

This is also how Necco Tags for avalanch rescue work.

Re:There are also other ways to do some of this. (1)

Capt.Albatross (1301561) | about a year ago | (#45222119)

There is another way to do that, which I believe is much more sensitive: Send the pulse on one frequency, listen for the return on a harmonic.

That is a really clever idea, but if you are doing this at radar frequencies (for spatial resolution) wouldn't the harmonics be difficult to detect? Would the semiconductor junctions of the size used in current semiconductor devices be sufficiently efficient radiators at the harmonic frequency?

On the other hand, perhaps you don't need the spatial resolution of radar for the applications mentioned in the article.

I am not an EE, as is probably obvious.
 

Re:There are also other ways to do some of this. (1)

Ungrounded Lightning (62228) | about a year ago | (#45229607)

... if you are doing this at radar frequencies (for spatial resolution) wouldn't the harmonics be difficult to detect?

Piece of cake. Just pick a fundamental where the second harmonic is in a quiet frequency. Your second harmonic signal will stand out like a sore thumb.

It's also phase-coherent with your transmitter so you can use a synchronous demodulator to pick it out of a hell of a lot of noise, if there is noise. Phase-locked is as narrowband and accurately tuned as it gets: Your bandwidth is the short-term stability of your transmitter over the round-trip time.

Would the semiconductor junctions of the size used in current semiconductor devices be sufficiently efficient radiators at the harmonic frequency?

Yep. Especially these days, when the only diodes in sight are likely to be the very fast anti-static diodes behind the pins of chips whose signals, which themselves, may be in the gigahertz range, and the parasitic diodes between the substrates and the active regions of even faster logic gates.

Of course a microwave diode, connected to wiring with a geometry optimized to act as an antenna at the two frequencies involved, will be still better.

Re:There are also other ways to do some of this. (1)

Capt.Albatross (1301561) | about a year ago | (#45227593)

There is another way to do that, which I believe is much more sensitive: Send the pulse on one frequency, listen for the return on a harmonic.

This is a follow-on to my earlier question, about the difficulty of receiving the harmonics of a radar-frequency interrogation pulse. If the pulse consisted of two distinct frequencies (or was transmitted in addition to a continuous illumination at a different frequency), would a diode or other nonlinear reflector generate a return signal at the beat frequency?

Re:Summary incorrect based on article (2)

TheLink (130905) | about a year ago | (#45220437)

Yeah there are many other ways of "seeing" through bubbles. Like range-gated cameras/radar/sonar.

That said I suspect dolphins mostly build a picture or even 3d model of the environment based on the perceived location of the reflections.

For example, say there is someone talking right in front of you, but you can still listen and aurally locate people who are talking further away behind that person. Even if the person in front is talking loudly, as long as he's not way too loud you can still detect the position of the other talkers and know where they are in the room. And the crucial difference from simple echolocation - you're not timing the echoes to figure out the distance of the talkers - there are no echoes! And yet you know the distance and location of the talkers just from listening alone!

So I think animal (including human) echolocation is an extension of this ability. They make sounds to produce "talkers" from the resulting echoes, and then they build a picture based on where the "talkers" are.

For example if there is nobody "talking" in the room you could clap your hands (or click your tongue) and hear the location of the echoes in the room. With practice you can identify the rough shape of the room and even location of large objects.

It's not a stretch to believe that first there was hearing ability, then the hearing ability was used to accurately locate noise making enemies, prey and objects. Then animal echolocation is just causing the silent objects "make noise" so they can locate them just the way they used to locate noisy objects from the sounds they make.

I haven't investigated if this is what dolphins (or bats) really do either, but my bullshit is just as plausible right? If not more so, but I'm biased ;).

But if they do things the way I describe it becomes obvious why the bubbles and background noises aren't necessarily big problem. In fact some background noises would just let you know the shape of the background without you needing to expend time and energy to "illuminate" them with your sonar.

Perception is everything, or so it appears to be (1)

TapeCutter (624760) | about a year ago | (#45220927)

The sensations of hearing, sight, touch, and to some extent smell are all different ways for the brain to model 3D space. Different ways for the universe to observe itself.

Human echolocation experient (2)

advid.net (595837) | about a year ago | (#45221221)

[...] you could clap your hands (or click your tongue) and hear the location of the echoes in the room. With practice you can identify the rough shape of the room and even location of large objects.

I suggest the /.ers to try this experiment, it's fun.

Best results in the dark, during a quiet night so you won't hear much background noise, yet close your eyes.
Snap your fingers while walking slowly (short whistle also works).

If you do this walking down a corridor, then you will guess where are the doors, the coats hanging, the turns and crossing very easily.

Re:Summary incorrect based on article (1)

jimbolauski (882977) | about a year ago | (#45222013)

I suspect it has more to do with having two ears and being able to filter out bubble walls. Two ears will give dolphins stereoscopic sonar pinpointing range add in the fact that they are familiar with the response from bubbles and visually can determine their depth and they could easily filter the bubbles returns.

Re:Summary incorrect based on article (2)

rkww (675767) | about a year ago | (#45222585)

The researcher did not actually investigate what it is that dolphins do, he thought of what they could possibly do. I would be more interested in finding out if this is actually the technique dolphins use or do they do something different?

Following links to here [discovery.com] we find:

"As for the dolphin: while acting as an inspiration for the technology, Leighton and his team later discovered this was not how the animals' sonar worked. Dolphins also send out twin pulses, but theirs vary in amplitude, not polarity, he said."

Re:Summary incorrect based on article (1)

Jmc23 (2353706) | about a year ago | (#45227879)

Thank you. Lot's of other people posting some quite interesting things, none of which had to do with dolphins :)

Now I know I'm going to have some weird dreams tonight trying to figure out how exactly dolphins perceive that!

Just so I'm clear... (3, Funny)

ArbitraryName (3391191) | about a year ago | (#45219895)

How many pulses do dolphins and this radar send, and what purpose does that serve?

Re:Just so I'm clear... (-1)

Anonymous Coward | about a year ago | (#45219937)

Have you tried reading the fine article?

Re:Just so I'm clear... (0)

Anonymous Coward | about a year ago | (#45220013)

Whoosh...

Re:Just so I'm clear... (1)

ArbitraryName (3391191) | about a year ago | (#45220093)

Not yet, I was hoping something like that would be covered in the summary.

Re:Just so I'm clear... (3, Funny)

plover (150551) | about a year ago | (#45220289)

How many pulses do dolphins and this radar send, and what purpose does that serve?

I'm sure it's all for a greater porpoise.

Re:Just so I'm clear... (0)

Anonymous Coward | about a year ago | (#45220313)

If you're going to make a shitty pun, at least have it make sense.

Re:Just so I'm clear... (1)

wonkey_monkey (2592601) | about a year ago | (#45221211)

Oh, lighten up. If anything, being only almost correct makes it funnier.

Re:Just so I'm clear... (1)

ebno-10db (1459097) | about a year ago | (#45222053)

How come there's no button for Score:-17, Bad Pun?

Re:Just so I'm clear... (1)

hamburger lady (218108) | about a year ago | (#45224399)

luckily, /. has no way to punnish someone that way.

Re:Just so I'm clear... (5, Funny)

Edis Krad (1003934) | about a year ago | (#45220303)

The number of pulses and the purpose were written in the summary twice in quick succession, to remove background noise.

Re:Just so I'm clear... (2)

AAWood (918613) | about a year ago | (#45221259)

You may think I accidentally copied your joke*. The truth is we made the same joke twice, in quick succession, to get through background noise.

*(despite specifically looking through the replies to see if someone had already done it before I posted... how did I miss this?)

Re:Just so I'm clear... (0)

Anonymous Coward | about a year ago | (#45224257)

Hey! you and the original poster made the same joke twice, in quick succession, to cut through background noise? cool!
I am repeating your meta-meta joke in quick succession so we can cut through background noise.

Re:Just so I'm clear... (2)

marcello_dl (667940) | about a year ago | (#45221685)

But, sadly, background noise increased.

Re:Just so I'm clear... (1)

game kid (805301) | about a year ago | (#45220483)

Apparently not one ping only.

Re:Just so I'm clear... (1)

AAWood (918613) | about a year ago | (#45221247)

I think it's clear the article summary was sending out two versions of the same sentence one after another to cut through background noise.

Any good EE already knows this (5, Informative)

Anonymous Coward | about a year ago | (#45219935)

http://en.wikipedia.org/wiki/Correlated_double_sampling

Re:Any good EE already knows this (0)

Anonymous Coward | about a year ago | (#45220509)

Re:Any good EE already knows this (0)

Anonymous Coward | about a year ago | (#45220641)

BTW, the "s" is rather important, what with bored, over-funded Cold War-era spies using their resources against We, the People:

"Does this need to be encrypted (Wikipedia)?" Not even WRONG.

"Can this be encrypted?" YES, easily.

The NSA/GCHQ may have subverted SSL/TLS to some extent, but not all algos and implementations, and not all the time. If you encrypt as much "uninteresting" traffic as you can (e.i., traffic that you wouldn't consider sending in the clear), less stands out as "interesting." Worse S/N ratio for them means better privacy for us.

How much noise can any adversary swallow up and decrypt? Surely not all of it. And if they can't do it all in real-time, they'll be burdened with a growing backlog.

Let's not get sloppy just because we're talking about dolphins or radar, please.

Re:Any good EE already knows this (1)

Anon, Not Coward D (2797805) | about a year ago | (#45225573)

beacuse we are talking about dolphins-- which send two pulses in quick sucession to cancel bakground noise-- is that it was posted twice, to avoid background noise

mod d03n (-1)

Anonymous Coward | about a year ago | (#45219943)

a BSD b0x that

Near Zero Information in the article (1)

BoRegardless (721219) | about a year ago | (#45219947)

I expected much more description of what the concept meant and how it worked.

Re:Near Zero Information in the article (2)

Longjmp (632577) | about a year ago | (#45220029)

Well, the summary describes it:
The radar "sends out two pulses in quick succession to cancel out background noise", like dolphins which "send out two pulses in quick succession to cancel out background noise".

I also think that sending out two pulses in quick succession may cancel out background noise.

*eyes rolling at 300 rpm*

Re:Near Zero Information in the article (2)

mrbester (200927) | about a year ago | (#45220059)

In this case the two pulses cancelled out the signal instead of the noise. Or the summariser is a relative of Foghorn Leghorn.

Re:Near Zero Information in the article (1)

Longjmp (632577) | about a year ago | (#45220089)

Or the signal cancels out the dolphins. Whatever.

Re:Near Zero Information in the article (1)

rts008 (812749) | about a year ago | (#45221041)

You forgot the standard prefix to your comment, comrade:

"In Soviet Russia...."

So, no fish for you, bad dolphin... ;-)

Re:Near Zero Information in the article (2)

Jah-Wren Ryel (80510) | about a year ago | (#45220117)

> I expected much more description of what the concept meant and how it worked.

Totally spit-balling but maybe it works like differential electrical signals. In short two signals inverted from each other, if there is any background noise it is canceled out when you subtract one signal from the other to get the desired waveform.

https://en.wikipedia.org/wiki/Differential_signaling [wikipedia.org]

Re:Near Zero Information in the article (4, Informative)

Required Snark (1702878) | about a year ago | (#45220295)

Follow the link and RTFM

Radar clutter suppression and target discrimination using twin inverted pulses [royalsocie...ishing.org]

The proposition that the use of twin inverted pulses could enhance radar is tested. This twin inverted pulse radar (TWIPR) is applied to five targets. A representative target of interest (a dipole with a diode across its feedpoint) is typical of covert circuitry one might wish to detect (e.g. in devices associated with covert communications, espionage or explosives), and then distinguish from other metal (‘garbage’ or ‘clutter’), here represented by an aluminium plate and a rusty bench clamp. In addition, two models of mobile phones are tested to see whether TWIPR can distinguish whether each is off, on or whether it contains a valid SIM card. Given that a small, inexpensive, lightweight device requiring no batteries can produce a signal that is 50dB above clutter in this test, the options are discussed for using such technology for animal tagging or to allow the location and identification of buried personnel who opt to carry them (rescue workers, skiers in avalanche areas, miners, etc.). The results offer the possibility that buried catastrophe victims not carrying such tags might still be located by TWIPR scattering from their mobile phones, even when the phones are turned off or the batteries have no charge remaining.

Re:Near Zero Information in the article (1)

Longjmp (632577) | about a year ago | (#45220337)

Meanwhile I've read all linked articles, and none of them describes how it actually works, which was GP's question.
Quoting an absolute meaningless part of TFA doesn't help either.

How it actually works, in my opinion (0)

Anonymous Coward | about a year ago | (#45222991)

Usual radar uses radio-frequency (usually microwave-frequency) pulses. Instead (I think), this radar uses baseband impulses, as used in impulse radio (also known as ultrawideband radio UWB). Each impulse starts at zero current into the transmitting antenna, increases to a peak current, then decreases back to zero current.

"twin inverted pulses" refers to emitting one impulse and listening for the echoes, and then emitting a second impulse (of the same shape but opposite current polarity) and listening for the echoes.

If the target is linear, the echoes from the two impulses will be the same shape and amplitude, but opposite polarity. If the target is nonlinear (say a diode connected across an antenna), the echoes from the two impulses will differ in shape and amplitude, as well as in polarity.

By summing the echoes from the two impulses, echoes from linear targets are cancelled and echoes from nonlinear targets do not cancel.
This is a nonlinear-target-indicator (NLTI) radar.

Peter Traneus Anderson

Re:Near Zero Information in the article (1)

wagnerrp (1305589) | about a year ago | (#45220323)

There's a bit of confusion over the meaning of background noise. In this example, it's not stray sound or RF, but reflections from things you don't care about. For dolphins, they're talking about air bubbles in the water. For this RADAR system, they're talking about brush and rubble. The idea of differential signalling does not apply here.

Basically, they're sending two pulses, shifted 180. They both bounce off the target, come back, and cancel each other out at the receiving antenna, yielding no response. It acts like a material discriminator, in that certain interesting materials, such as wires or micro-circuitry, invert only one of the reflections, so instead of cancelling each other out, they amplify.

Why this inversion of only one of the reflections happens, rather than both... I have no idea. I'm merely repeating the claims in article.

Re:Near Zero Information in the article (2)

Longjmp (632577) | about a year ago | (#45220471)

Since none of the articles explains technical details, I can only speculate about the dolphins (which is more interesting anyway).
If their second "click" is used as a reference signal, i.e., the signal itself, not its echo, it could be used not only to invert the first signal and filter out the noise, but also give information about the distance:
Depending on when the reflected echo comes in - delayed (and overlaid) - to the reference (second) signal it would also account for the distance of the target.

Re:Near Zero Information in the article (1)

Jah-Wren Ryel (80510) | about a year ago | (#45220825)

It acts like a material discriminator, in that certain interesting materials, such as wires or micro-circuitry, invert only one of the reflections, so instead of cancelling each other out, they amplify.

The discussion of "twin inverted pulse sonar" clearly states that one signal is inverted from the other. So if only one signal gets inverted during reflection they aren't amplifying, they are canceling.

Seems more likely that "hard" objects cleanly invert both signals while "noisy" ones like bubbles or brush fuzz up both signals, essentially adding noise that the receiver can then subtract by subtracting the two signals. In which case this is classic differential signaling.

"As its name suggests, TWIPS uses trains of twinned pairs of sound pulses. The first pulse of each pair has a waveform that is an inverted replica of that of its twin. The first pulse is emitted a fraction of a second before its inverted twin."
http://www.sciencedaily.com/releases/2010/11/101117104502.htm [sciencedaily.com]

Re:Near Zero Information in the article (1)

wagnerrp (1305589) | about a year ago | (#45221735)

This is a three year old article? This is a much worse than normal delay for slashdot....

Re:Near Zero Information in the article (1)

Jah-Wren Ryel (80510) | about a year ago | (#45221799)

No, it is a sonar-only one to the 2013 radar version.

Re:Near Zero Information in the article (1)

ebno-10db (1459097) | about a year ago | (#45222183)

It's more clever than that. Here's a sonar explanation anyway:

http://resource.isvr.soton.ac.uk/FDAG/UAUA/RESEARCH/echolocation%20and%20bubbles/echolocation%20and%20bubbles%201.htm [soton.ac.uk]

It involves clutter (e.g. bubbles) having non-linear reflections (presumably because they're compressible), hence they have both even and odd harmonic reflections. Something from a harder object will have only odd harmonics. Adding the reflections from two pulses, one of which is inverted, will cancel the even harmonics of the clutter.

Re:Near Zero Information in the article (1)

jimbolauski (882977) | about a year ago | (#45222137)

There's a bit of confusion over the meaning of background noise. In this example, it's not stray sound or RF, but reflections from things you don't care about. For dolphins, they're talking about air bubbles in the water. .

That's because it is called clutter, the royal society article title Radar clutter suppression and target discrimination using twin inverted pulses I suspect minty3 did not RTFA or even has the slightest understanding of Radar, my theory is given more weight by the poor summary. He probably skimmed the 1st paragraph of one of the puff piece articles he linked to and called it good.

Hunting technique? (0)

Anonymous Coward | about a year ago | (#45220043)

I thought they used frickin' lasers.

Re:Hunting technique? (1)

ArbitraryName (3391191) | about a year ago | (#45220173)

You're thinking of sharks.

Mm non quc t Cánh Thiên Thn (Angel Wings (-1, Offtopic)

angelwings (3407451) | about a year ago | (#45220053)

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But does it... (0)

Anonymous Coward | about a year ago | (#45220055)

cancel out background noise?

Re:But does it... (4, Funny)

aXis100 (690904) | about a year ago | (#45220231)

Only if the device sends out two pulses in quick succession, which resembles the way dolphins send out two pulses in quick succession to cancel out background noise.

Re:But does it... (1)

MF4218 (1320441) | about a year ago | (#45220445)

The one time I do not have mod points.. which does not resemble the way dolphins send out two pulses in quick succession to cancel out background noise.

Re:But does it... (0)

Anonymous Coward | about a year ago | (#45220263)

Only if you send out two pulses in quick succession, I think.

Re:But does it... (0)

Anonymous Coward | about a year ago | (#45220767)

What's the purpose of sending out two pulses in quick succession, though?

OMG I read the article... (2)

faffod (905810) | about a year ago | (#45220315)

Reading the summary I was wondering if this would have any applications to improve detection of stealth aircraft. So I *gulp please don't mod me to oblivion* read the article. It's light on details, but not what I expected from the summary. The guy was able to build a sonar, followed by a radar that is able to distinguish between different materials. It's potential uses are for detecting explosives hidden in rubble and such, and for finding buried victims after some form of disaster (specifically homing in on their phones and other such devices). Oh, and it's cheap, if you know what you're doing you can build it for two bucks.

Re:OMG I read the article... (0)

Anonymous Coward | about a year ago | (#45220413)

Any /. reader worth his salt can extrapolate the substance of a FA by using the force alone. The trick is to then concentrate on some tangential story ark which may or may not involve Obama and his dastardly plan to provide free hearing aids for foreign dolphins (unless of course they've served in the navy in which case you try to delay the hearing aid program because all the dolphins obviously haven't heard about it).

Re:OMG I read the article... (0)

Anonymous Coward | about a year ago | (#45221167)

because all the dolphins obviously haven't heard about it

Which is why they need the hearing aid.

Re:OMG I read the article... (0)

Anonymous Coward | about a year ago | (#45222463)

I doubt this would help in finding stealth aircraft. Radar typically 'sees' an aircraft by sending out radio waves(obviously), and then waiting for the return. Some materials are able to reduce the amount of return, which is one way of having a stealth craft. The primary way of making a craft stealthy, though, is to make the surfaces of the craft out of flat, angled surfaces. These flat, angled surfaces then reflect the radio waves in different directions, but not back towards the source radar. So, the radar is waiting for a return that never comes back. Stealth aircraft are said to have a radar cross-section smaller than a mosquito, so it's safe to say the return is negligible.

Sending out two pulses in rapid succession just means: The material absorbs/dampens the return in rapid succession, and the flat, angled surfaces reflect the radio waves in rapid successions.

Of course I could be wrong, but I doubt this technology will help identify stealth craft.

Prior art (1)

lapm (750202) | about a year ago | (#45220459)

Wonder if that's patentable since there's clearly prior art on nature then...

Re:Prior art (2, Insightful)

Anonymous Coward | about a year ago | (#45220541)

Wonder if that's patentable since there's clearly prior art on nature then...

Easy, you just sequence the dolphins DNA and patent that.

hmmm (1)

wgoodman (1109297) | about a year ago | (#45221191)

I wonder if the device sends out two pulses in quick succession to cancel out background noise?

Dolphins inspire new way of writting summary (1)

Anonymous Coward | about a year ago | (#45221407)

Like dolphins, the device sends out two pulses in quick succession to cancel out background noise. The findings, published in the journal Proceedings of the Royal Society A: Mathematical and Physical Sciences, explained how the device resembles the way dolphins send out two pulses in quick succession to cancel out background noise."

Quickly copy and paste the same line twice then add crap in between to create echo chamber effects.

Blind people already knows how to do this (0)

Anonymous Coward | about a year ago | (#45221437)

I've seen them mapping out obstacles in a room by rapidly clicking their tongue or snapping their fingers.

Not Patentable (1)

pubwvj (1045960) | about a year ago | (#45221773)

Things like this need to be banned from the patent office as unpatentable due to prior art. This rule needs to be dealt out retroactively - should clear up a lot of the bad patents.

Re:Not Patentable (1)

ebno-10db (1459097) | about a year ago | (#45222245)

Otherwise some patent troll will go after the dolphins. This may be the only way to kill the trolls - they can be cited for interfering with wildlife or something. Kind of like getting Al Capone on tax evasion, though if you ask me, Al's business model was more ethical than the trolls'. At least he delivered product.

Re:Not Patentable (1)

LeadSongDog (1120683) | about a year ago | (#45223143)

Hmm, if someone's been paying license fees only to have the patent retroactively ruled invalid, can they get a refund from the troll?

The main point is... (1)

fahrbot-bot (874524) | about a year ago | (#45225559)

From TFA:

The results offer the possibility that buried catastrophe victims not carrying such tags might still be located by TWIPR

... Search and Rescue teams need to switch from using dogs to dolphins - duh.

Think of how many more people could be quickly found in building rubble or IEDs found by battlefield personnel if the teams were using search dolphins. The military could even equip them with lasers to support combat operations with, unlike sharks, no need for night-vision goggles. Think of the real-world applications people.

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