地形辅助导航系统以地形高程特征为定位信息源，可为水下航行器提供有界的定位误差，并能显著地抑制捷联惯性导航系统的误差漂移。而地形匹配算法是地形辅助导航系统的关键技术，其输出的匹配位置可作为组合导航滤波器的观测值以修正导航参数，地形匹配精度直接决定了整个导航系统性能。首先概述了现有水下导航定位技术，然后阐述了地形辅助导航基本原理与组成，最后详细总结了中外地形辅助导航系统和地形匹配算法的研究进展，为中国地形辅助导航系统的开发和研制提供有益参考和支撑。

The terrain aided navigation system relies on terrain elevation features as the source of positioning information, providing bounded positioning errors for underwater vehicles. Substantial suppression of error drift in strapdown inertial navigation systems is achieved. The terrain matching algorithm is the key technology of terrain aided navigation system, and its output matching position can be used as the observation value of the integrated navigation filter to correct the navigation parameters. The accuracy of terrain matching directly determines the performance of the whole navigation system. An overview of existing underwater navigation and positioning technologies was presented. Subsequently, the fundamental principles and components of terrain aided navigation were expounded. Finally, a detailed summary was provided regarding the domestic and international research progress on terrain aided navigation systems and terrain matching algorithms. This offers beneficial reference and support for the development and research of terrain aided navigation systems in our country.