Fast Localization Using Magnetic Beacon Based On Feather Vector For Harsh Environment

In recent years,with the improvement of people's life quality and the complexity of living environment,many new requirements have been put forward on the accuracy and robustness of navigation and positioning technology.Therefore,many kinds of navigation and positioning technologies have emerged.However,due to the weak penetration of satellite signals and multipath effects,the traditional satellite navigation and positioning technology cannot provide high-precision positioning services or can't work in indoor,mine,underground and other environments.The error in INS will accumulate over time.The INS cannot provide continuous high-precision positioning service.Artificial lowfrequency magnetic field has the advantages of strong penetration,easy identification,and without multipath effect.Therefore,using artificial low-frequency magnetic field has great potential for positioning in complex environments.This paper studies the lowfrequency magnetic field positioning technology based on feature vectors.Firstly,the basic theories related to the positioning technology of single magnetic beacon based on feature vector are analyzed and introduced by using the single magnetic dipole model.The magnetic field intensity of a magnetic beacon at a certain point in space is derived by using the single magnetic dipole model,the relative orientation of the target is calculated by using the extracted eigenvector,and the relative distance is calculated by using the scalar value of the eigenvector to locate the static target.Then,the thesis analyzes the problems such as the harsh environment of the positioning system,the structural error of magnetic beacons,and the non-alignment of magnetic beacons with the global coordinate system.The error caused by the single magnetic beacon system is analyzed and the corresponding calibration compensation scheme is proposed.The influence of the deviation of the magnetic beacon center,the error Angle of the magnetic moment and the non-alignment of the magnetic beacon with the global coordinate system on the positioning result is analyzed.In this paper,the corresponding optimal positioning method is proposed to improve the positioning accuracy.Then,based on the error analysis in Chapter 3,the optimization idea of multimagnetic beacon positioning scheme is proposed.Using the geometry composed of multiple magnetic beacons and targets in the target active area,a nonlinear equation positioning scheme and geometry The positioning scheme improves the positioning accuracy of magnetic beacon positioning technology based on feature vectors in complex environments.Furthermore,multi-magnetic beacon positioning technology requires multiple magnetic beacons to be placed in advance and multiple drivers are required to drive the magnetic beacons simultaneously.It takes more time and more energy.In this section,a magnetic field gradient magnetic sensor array positioning scheme based on a single magnetic beacon and magnetic beacon positioning technology based on geometric theory are proposed.Successfully reduced the preparation of location while ensuring the positioning accuracyFinally,this chapter studies the positioning of dynamic targets,It begins to study the difference between dynamic target and dynamic target localization process,combined with the motion model of the dynamic target,the positional relationship between the beacons in the multi-magnetic beacon,each beacon and the moving target Based on the relationship between relative pitch angle and asynchronous magnetic field gradient content,a dynamic target tracking method based on particle filter algorithm in the lowfrequency magnetic field is proposed,and a high-precision target tracking scheme is realized.