一种适用于地磁梯度匹配导航的ISCCP算法

An ISCCP algorithm for geomagnetic gradient matching for navigation

针对迭代最近等值线点(ICCP)算法在地磁变化平缓的区域匹配误差大,甚至出现误匹配的问题,本文首先建立ICCP算法的误差模型,阐明ICCP算法在这些区域匹配误差大的原因,并基于该误差模型,提出适用于地磁梯度匹配导航的迭代搜索最近等值线点(ISCCP)算法,该算法在ICCP的基础上改进了最近点搜索方式,利用地磁3个正交方向梯度信息进行迭代搜索。最后通过仿真实验表明,ISCCP算法平均点位误差能控制在半个网格长度以内,精度相较于ICCP算法提高了约15倍,有效解决了ICCP算法在地磁变化平缓的区域匹配误差大的问题。

The iterated closest contour point(ICCP) algorithm results in large matching errors and even false matching in areas with small geomagnetic variations. Given this, this study established an error model for the ICCP algorithm in order to determine the causes of the large matching errors in the areas. Based on this model, this study proposed an iterated search closest contour point(ISCCP) algorithm suitable for geomagnetic gradient matching for navigation. In the proposed algorithm, the closest point search method was improved based on the ICCP, and an iterative search was performed using the geomagnetic gradient information of three orthogonal directions. The simulation results show that the average point error of the ISCCP algorithm can be controlled within half a grid length, with a precision about 15 times higher than that of the ICCP algorithm. Therefore, the ISCCP algorithm proposed in this study can effectively eliminate the large matching errors in areas with small geomagnetic variations caused by the ICCP algorithm.