Sounds like a very interesting system and has potential market value.
My only concern besides the cost would be the posible harm the ultrasound waves may do to the fish and other wild life?
The Navy is in hot water over those wales and there new hipowered sonar system.
There is a company that has developed a system that uses satalites and repeaters to relay telemitry to divers and vedeo link and its live.
Hate to know the cost of that baby!
Great research you are doing and keep us posted I am very interested !
Dave amur Ship Yard