Geomagnetic Matching Algorithm Based On Multi-feature Quantity And Its Application

Geomagnetic navigation is a kind of navigation technology which uses geomagnetic characteristic information to match and locate.In recent years,with the development of integrated navigation technology,the integrated navigation of geomagnetic aided inertial navigation has become a research hotspot at home and abroad.In this dissertation,the geomagnetic field model establishment,geomagnetic matching algorithm and inertial / geomagnetic integrated navigation are studied in geomagnetic navigation.The main works are as follows:Based on the international geomagnetic reference field model,the selection criteria of geomagnetic field and geomagnetic characteristic quantity are ana lyzed.Considering that most of the existing geomagnetic matching algorithms only consider the single characteristic quantity,that is,the geomagnetic total intensity.The influence of vertical intensity and horizontal intensity on geomagnetic matching is ignored.In this dissertation,based on the fluxgate sensor,which can measure multiple features,a matching method using multiple features is proposed in the flat area of geomagnetic transformation.The geomagnetic matching algorithm is studied.Firstly,the commonly used MAGCOM and ICCP algorithms are analyzed.Because the principle of MAGCOM algorithm is relatively simple,the simulation analysis shows that the accuracy of the algorithm is not high,and the course error of trajectory can not be correct ed by ICCP algorithm,although ICCP algorithm can correct the course error existing in trajectory.But because of the influence of the initial condition,when the initial error is large,the matching will go wrong.Based on the above analysis,this dissertation studies the artificial fish swarm algorithm,which makes use of the idea of swarm intelligence.It can effectively search for the real track on the geomagnetic map.In this dissertation,the measure criterion of fish swarm algorithm is improved firstly,Hausdorff distance is combined with artificial fish swarm,and Hausdorff distance is used as the new evaluation criterion of fish school.However,the success rate of matching is not high in the geomagnetic flat area.A multi-feature matching algorithm based on artificial fish swarm is proposed,in which the total intensity,vertical intensity and horizontal intensity of geomagnetism are used to match.When the matching length is too long,the problem of less matching times is improved.Finally,the simulation results show that the algorithm has a good matching performance in the geomagnetic flat area.The filtering of integrated navigation system is studied.The loose combination and tight combination modes of geomagnetic aided inertial integrated navigation are analyzed,and the inapplicability of tight combination in the area of geomagnetic flat is explained.The state equation and observation equation are established by using loose combination method.The simulation results show that this method can navigate well in the geomagnetic flat area.