Three main acoustic positioning systems (Fig. 3) used for localization of AUVs are introduced and discussed. They are short baseline (SBL) systems, ultra-short baseline (USBL) systems and long baseline (LBL) systems. The transponders of SBL and USBL systems are deployed on a anchored ship or pier before the start of mission. LBL systems require transponders to be mounted on the seafloor before localizing AUVs. These three acoustic positioning systems are stated as below.
1) Short Baseline: Short baseline (SBL) systems deter- mine the position of a tracked AUV by measuring its distance from three or more transducers that are mounted under a ship or pier. For improving the accuracy of positioning system, a pressure sensor…
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