In-situ calibration of transceiver alignment for a high-precision USBL system

Positioning accuracy of an ultra short baseline (USBL) tracking system may significantly decrease with the increasing of alignment errors resulted from sensors installation. This paper proposes an algorithm to estimate the angular misalignments of a high-precision USBL transceiver relative to attitude sensors. The calibration algorithm presented is based on the positioning errors caused by heading, pitch, and roll misalignments, when running a survey around a seabed transponder. The Sea-trial results show that the trajectory estimation of vessel by calibrated system is coincident with that determined by DGPS. The method presented in this paper therefore is proved to improve the position precision effectively.