Research on underwater terrain-matching method based on double round template

Underwater terrain-matching aided navigation is one of the key technologies for navigational positioning of underwater vehicle. Compared to the underwater terrain-matching algorithm based on single-beam sounding system, the two-dimensional array single template matching algorithm based on multi-beam sounding system is characteristic of more information contents of terrain matching, higher matching accuracy and longer matching time. In this paper, a double round template was extracted from single template and two-dimensional elevation information were mapped into a grey-scale image. The Zernike matrix of this grey-scale image was calculated and the optimum matching position was determined through correlation computation. The simulation results demonstrated that this new method could shorten matching time effectively while maintaining high underwater matching accuracy.