Acoustic differential delay and Doppler tracking system for long range AUV positioning and guidance

An acoustic positioning and guidance technique, based upon differential delay and Doppler tracking system, is proposed for long distance 2D navigation and path planning on board, autonomous underwater vehicles (AUVs). This system is also easily extendable to short distance 3D positioning and guidance with the use of a bottom echo sounder on board the AUV. For positioning purpose, the system uses a single low-cost omnidirectional hydrophone mounted on the AUV, and is associated to an external (fixed or towed) dual frequency transmitting subsystem. This technique can be viewed as a combined version of classical long base (delay) and short base (Phase) trajectography. For path planning and AUV guidance, the predicted route is described as a sequence of iso-differential delay and/or iso-differential Doppler segments.