相关地磁匹配定位技术

地磁匹配定位算法的本质是数字地图匹配，相关匹配算法是数字地图匹配的有效算法。在地磁导航中该匹配算法自适应实时构造基准数据序列，并以Hausdorff距离作为相关判断准则。为了提高了算法实时性，提出了预匹配和精匹配相结合的改进措施优化了运算过程。在预匹配过程中，由于地磁数据的离散性，搜索步长定为一个基本网格单元，并与序贯相似检测原则相结合，这样可快速排除非匹配区，筛选得到精匹配所需要的可行区域。在精匹配中，引入了双线性插值法对地磁场原始数据进行加密内插以提高匹配精度。最后利用地磁场数据进行了仿真试验，结果表明在一定条件下该相关匹配算法对地磁导航具有适用性。

Geomagnetic matching location using correlative method

The geomagnetic matching technology was investigated, and a correlation matching algorithm was presented. The algorithm constitutes the referenced data sequence real-timely and adaptively, and adopts Hausdorff distance as correlative determining principle. The pre-matching and precise-matching were proposed to reduce the computing complexity and time. In pre-matching, the searching strategy defines a gridding unit as a step with SSDA method, so it can quickly eliminate non-matching area and gain feasible area for precise-matching. In addition, the dual-linear interpolation was introduced for further matching. Simulation experiment confirms that the correlation matching algorithm is applicable for geomagnetic navigation in certain condition.