SparkFun Forums

[strefli3]

Ultimately I would like to source an off the shelf solution for underwater communication. Unfortunately the ones I have found are rather large and fairly expensive. If anyone has a solution I'd like to hear it.

Making one might not be too difficult either:

http://courses.cit.cornell.edu/ee476/Fi ... index.html
http://cseweb.ucsd.edu/~kastner/papers/ ... _modem.pdf
http://cseweb.ucsd.edu/~kastner/researc ... munication

Thanks in advance,

[MichaelN]

As you say, it shouldn't be "too difficult" to copy an existing ultrasonic modem, if you have some experience with electronics.

If you need longer range than can be achieved by ultrasonics, you may like to look at using blue lasers. I have heard that certain navies are experimenting with blue lasers for communicating with submarines, which are currently limited to extremely low data rates (ie, a few bits per second at best) when fully submerged.

[MichaelN]

If you need longer range than can be achieved by ultrasonics, you may like to look at using blue lasers...

I just noticed that some of those ultrasonic units are capable of very long ranges - several km. I had no idea they were capable of such ranges with those power levels...