Ping intensity dropoff

Hi, i am wondering if anyone has a good model for the intensity drop for the ping 360?

I am familiar with standard relationships, such as, I~1/R^4. However, it would be great if a more specific model has already been developed.

I am very keen on compensating for the intensity drop due to range. E.g a the same object should (after compensation) return the same intensity regardless of range. Note that i am aware of effects of angles etc.

Best,
Ole Haaland

Hi Ole,

Intensity drop outside of just spread is largely dependent on the properties of the water (e.g. ion content, temperature) and macro-effects in it (e.g. bubbles, dirt/silt, fish, temperature changes), as well as the frequency of sound being considered. If your ROV is moving relative to the things being scanned, it may also be relevant to consider the doppler effect, since the transducer sensitivity is frequency dependent, although I imagine this isn’t a particularly large source of error in most cases.

This calculator takes in water and sound properties and gives back the acoustic absorption rate estimates from three different models. It also links to an explanation of the underlying physics, and provides references to the articles the models were developed in :slight_smile:

Note that the calculator doesn’t consider macro-effects in the water, so the actual results may vary.