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Why did the Sonar Experts Fail to Solve the Problem?

How, you ask me, can a lone mathematician/inventor/computerist in Baton Rouge have solved the Dolphin Sonar Problem when MIT and the navies of the world have not?! Seems unlikely.

Perhaps the problem was, in fact, solved earlier and has been a military secret. If this is so then readily avaiable information on the "echolocation" of dolphins might be distorted by omission and by misdirection from people working for government.

But, not every capable researcher in the world is bound by military secrecy.

So, perhaps I have not solved the problem and my more than 15 years of simulations are illusions. That, objectively, is a possibility. Indeed, that would, were I on the outside looking in, be my main guess.

Here is an outline of the "solution to the dolphin-sonar problem:"
The "theory" which inspired the "echoscopic" methods starts like this: the jaw of the dolphin has thousands of sensors, probably modified touch-sensors, that respond exquisitely to echoes of "clicks" and send time-of-arrival information directly into a "sonic retina" in the brain, by-passing the cochlea. Small parts of the brain "triangulate" upon small (say 6 sensors) subsets of the sensors. Each set can produce a small, diffuse, part of an over-all "mental image" of echoing objects. Thousands of such small sets of information are processed "in parallel," which is to say, simultaneously, in separate neuronal subunits. The thousands of partial images combine into one "mental" image. The image from one click can be enhanced by the image from the next - if it comes along soon enough. The images may lack depth-accuracy, but perhaps not much worse so than one-eyed human vision.

Suppose that simple, partial theory is correct and is at least a first stage of the problem. That creates the puzzle -- did teams of experts fail to anticipate the anatomy that now seems an obvious possibility?

I suspect that, until recently, many experts all assumed that dolphins have only two ears -- or, in words that give clarity to the mistake, only two acoustic sensors. That the size, in dolphins, of the two auditory nerves, that lead from the frequency-analyzing cochlea into the brain, is larger than in humans suggests that frequencies in the hearing of dolphins are important to them. And surely they are important - for uses other than high-resolution sonic imaging.

Then, believing the frequency-analyzing cochlea to be involved, the powerful spectral tool of Fourier Analysis was used. And that could have been a hugely distracting consumer of mental energy.

By contrast, I use geometry that is 2300 years old (as augmented by Rene Descartes much more recently). And is easy, by comparison.

More "tricks" to making Echoscopy practical are not yet revealed pending patent-protection.

To be continued ...

You can ask me about these things or correct my errors via doug@dolphininspiredsonar.com
August 2013