改进的地形熵算法在地形辅助导航中的应用

地形辅助导航是水下航行器导航技术的一个发展新方向，但它并不能够在任何地形区域都可以工作，比如在平坦区域的导航效果很差。通过计算不同区域的水深标准差，选择地形特征独特的区域作为适配区域。基于熵的算法对于地形复杂区域的匹配分析是快速有效的，但传统的地形熵算法匹配精度不高，本文引入了地形差异熵的概念并对其进行改进，在选定的地形区域使用MATLAB软件进行了仿真研究。仿真结果表明，改进的地形熵算法在选定的地形区域位置误差在250m左右，可以满足水下航行器的导航要求。

Application of modified terrain entropy algorithm in terrain aided navigation

Terrain-aided navigation is a new direction of underwater vehicle navigation technology,but it is not suitable for any area and its navigation effect on flat area is not satisfied.By computing the standard deviation of water depth,the area of unique terrain feature was chosen as the matching area.The algorithm based on entropy was fast and effective for analyzing the matching of complicated area.But the precision of traditional terrain entropy matching algorithm was not good,so terrain variance entropy was introduced to improve the algorithm.MATLAB was used to simulate the algorithm in the chosen area.Simulation result shows that position error of improved terrain entropy algorithm is about 250 m,which can satisfy the navigation demand of underwater vehicle.