A novel feature extraction method of direction navigability analysis for geomagnetic navigation

摘要

In geomagnetic navigation, the estimation of vehicle's location is only reliable when the matching method is used in some magnetic areas and directions. In order to evaluate the applicable directions, effective direction matching features (DMFs) play an important role. Aiming at this problem, a novel feature extraction method based on the slice lines of the magnetic surface is proposed. Firstly, the demerits of current feature extraction methods are analyzed. Secondly, principle of the proposed method is illustrated and a description system of the DMFs is established based on the slice features. Then in the view of pattern recognition, a BP neural network is trained to evaluate the direction navigability of a magnetic area. Finally, geomagnetic matching experiments arc conducted to prove the validity of the slice features. Compared with the features obtained from the Gray Level Co-occurrence Matrix (GLCM), the proposed method is able to extract the features in any direction of the magnetic area and has a higher stability in classification as well.