An assisted navigation method based on geomagnetic matching

Abstract

In view of the problems of easy loss of satellite signals and divergence of inertial navigation system in navigation, various assisted navigation methods have emerged. Geomagnetic matching navigation has gradually become an important part of integrated navigation due to the characteristics of concealment, all-weather and no accumulation of errors. Traditional matching algorithms are sensitive to heading error and initial position error. Moreover, the intelligent algorithms are computationally complex and cannot meet the real-time requirements of navigation. Therefore, combined with the affine model, this paper proposes a scale-adaptive tower search method for geomagnetic matching navigation. This method selects the initial matching points by contour constraints, which improves the search efficiency. In addition, matching evaluation indicators are introduced to dynamically adjust search scales, which achieves both global searching and local positioning. The simulation results verify that the method can effectively correct the error of the inertial navigation system, and can meet the real-time requirements while ensuring the matching accuracy.