AQUA-METRE D100 is a local underwater positioning system based on a principle of 3D acoustic interferometry (USBL).
It is particularly well-suited to precision metrology over a radius range of 150m.
It is a simple system to use and is totally standalone (no cable between seabed and surface), so it can be used by a diver alone.
Preparation for the dive and retrieval of measurements are done via a PC and an infrared link; measurements can be transferred in .dxf format (compatible with many CAD programs).
The system is self-calibrating and does not require a velocity sensor (measurement of acoustic velocity on initialisation).