A Calibration Method of Underwater Transponder Position Based on Maximum Correntropy

Abstract

The ultra-short baseline(USBL) positioning system is widely used in the integrated navigation and positioning of underwater vehicles. Knowing the precise position of the transponder is a prerequisite for the application of the USBL system for navigation and positioning. The traditional calibration method of transponder position takes the slant distance as the observational variable. The calibration accuracy is not high, and the robustness is poor. The linearized measurement equation based on the Kalman filter was derived by taking slant distance and bearing angles as observational variables in this paper. In view of the non-Gaussian distribution of noise caused by complex underwater environments, a maximum correntropy filtering method was used to calibrate the position of an underwater acoustic transponder by suppressing outliers. Calibration experiments on the transponder position were carried out under the typical environment of the Yangtze River. Experimental results show that the proposed calibration method has higher calibration accuracy than the traditional method. It has better robustness under outlier interference. After calibration, the positioning accuracy of the USBL system has been improved by 48.3%, 48.2%, and 40.4% in the east-north-up coordinates. It can provide high-precision navigation and positioning functions for underwater vehicles.

Keywords

• error calibration
• undersea vehicle
• maximum correntropy
• transponder
• ultra-short baseline
• navigation and positioning