航海图水深模型用于水下地形匹配定位的选取分析

Selection Analysis of Nautical Chart Used in Underwater Terrain Matching Location

系统分析了航海图水深模型(DDM)直接应用于水下地形匹配定位的可行性,给出了航海图DDM作为水下地形匹配基准图时比例尺的选取要求。首先,在经典TERCOM算法的基础上,构建基于航海图DDM的水下地形匹配定位算法;然后,将地形标准差不同的2个试验区均匀地划分为100个匹配区,并构建比例尺为1∶20 000到1∶200 000的航海图DDM;最后,分别以这些航海图DDM作为匹配基准图,进行匹配定位试验。试验结果表明:(1)改进后的TERCOM算法可以直接采用航海图DDM作为地形匹配基准图进行匹配定位;(2)为减少误匹配的发生,应选取比例尺大于1∶25 000的航海图DDM作为地形匹配基准图。

This paper makes a research of under-water terrain matching algorithm based on navigation DDM and presents a basic scale limitation of navigation DDM as reference map. Firstly,an improved under-water terrain matching algorithm based on navigation DDM developed from traditional TERCOM is put forward.Then,two experiment sea areas with different SD（ standard deviation） are divided into 100 matching areas,a series of navigation DDM with scale differs from 1 ∶ 20 000 to 1 ∶ 200 000 are built.Lastly,terrain matching location experiments are done with different DDM. All the experiments show：（1） The improved TERCOM can use navigation DDM as reference map to locate;（2）Navigation DDM with scale larger than 1 ∶ 20 000 shall be chosen in priority to reduce the probability of error location.