The Research of Matching Area Selection Criterion for Gravity Gradient Aided Navigation

Matching area selection is the basis of the gravity gradient aided navigation. In this paper, a criterion for gravity gradient matching area selection is proposed based on the gravity gradient tensor matching location, feature extraction and analysis. Matching position experiments on the gravity gradient tensor map are tested by sliding window, and the optimal matching areas on the basis of the gravity gradient tensor maps were found. By means of the gravity gradient feature parameters extraction for the optimal matching areas and analyzing the performance impact of the gravity gradient feature parameters to matching accuracy, a criterion for gravity gradient matching area selection is obtained. Making use of the proposed matching area selection criterion and the average absolute deviation (MAD) matching algorithm, the gravity gradient aided positioning simulation results show that the effect of the matching navigation in the adaptation area is markedly superior to the effect in the non-adaption area, the position error is less than a grid, and matching rate is greater than 90%.