重力辅助导航匹配区域选择准则

Selection criterion for matching area in gravity aided navigation

通过在重力场区域中移动局部计算窗口的方法,计算了实测重力场各个局部的多种统计特征并使用填色等值线图进行了对比和分析,以局部重力场的标准差和经纬度方向相关系数作为匹配区域选择的数量指标,给出了重力匹配区经验选择准则。采用均方误差和平均绝对差算法在实测重力图上对重力辅助惯性导航系统进行了仿真研究,计算结果表明,在满足重力匹配区选择准则下进行的重力辅助导航,其导航系统定位误差小于一个重力图网格,匹配率大于90%。

The various statistical characteristics of each measured local gravity field was calculated by sliding the local computing window on gravity map, and the comparison and analysis were made using color-filled contour maps. The empirical selection criterion of gravity matching area was given by using local gravity standard deviation and local gravity correlation coefficient as quantity indexes for selecting gravity-matching area. Using these quantity indexes, some areas are selected as suitable matching areas, and the simulations were made in these areas using mean-square-error and mean-absolute-difference algorithms for correlative matching. The results show that the gravity aided navigation system can achieve good performance in the regions selected by the selection criterion. The matching error is less than one grid on the gravity map, and the matching rate is above 90%.