基于重力测量卫星的重力梯度辅助导航研究

摘要

The inertial navigation system’s (INS) position error grows larger and larger as time goes on;it is likely to happen that no satellite signal to amend the INS ’s instrument in wartime ,therefore ,there is a growing emphasis on the gravity gradient aided navigation technology which is completely independent .This paper focuses on the gravity gradient aided navigation key technologies ,and in order to overcome the defect that navigation accuracy of gravity gradient aided navigation algorithm is not high in large initial matching error ,the at‐tenuation absolute difference algorithm is introduced to gravity gradient aided navigation , meanwhile ,improved the sampling strategy to avoid the bad real‐time defects .Simulation results show that the accuracy of gravity gradient aided navigation is a grid around ,even in the case of larger initial errors .%惯性导航系统的误差随着时间而不断累积，而战时很可能无卫星信号来校正惯导仪器，因此，完全自主的重力梯度辅助导航技术越来越受到重视。本文以亚音速飞行的巡航导弹为例，分析了重力梯度匹配辅助导航系统的关键技术，并针对等值线匹配算法在大初始误差条件下易陷入局部最优点的问题，引入了衰减绝对差算法进行粗匹配，同时，改进了其采样策略，避免了实时性差的缺陷。仿真结果表明，重力梯度匹配辅助导航的精度限制在一个网格，且能适应大初始误差的情况。