A Navigation Satellites Selection Method Based On ACO With Polarized Feedback

With the continuous development of Galileo and Beidou satellite navigation systems,and the ongoing modernization of GPS and GLONASS systems,navigation has been in a new era of multi-system integration application,providing more possibilities of navigation and positioning for military and civilian production and life.Meanwhile,with the advent of information and intelligence era,various applications also put forward higher accuracy and real-time requirements for navigation and positioning.Satellite selection is to select the most appropriate subset from all visible satellites for navigation solution,so as to avoid the calculation burden brought by the solution using all satellites;at the same time,whether the selected subset is reasonable and effective is related to the accuracy and real-time of the subsequent solution.Therefore,the research on satellite selection method is of great significance.In this dissertation,a method based on ACO with polarized feedback(ACO-PF)is proposed to select the optimal satellite subset.The main contents and innovations of this dissertation are as follows:(1)In this dissertation,the existing satellite selection criteria based on Geometric Dilution of Precision(GDOP)are studied,and the new criterion called weighted GDOP considering both elevation angle and signal-to-noise ratio(ES-WGDOP)is proposed.Based on the study of GDOP and WGDOP,and combined with the typical satellite positioning error factors,the ES-WGDOP satellite selection criterion is proposed,which considers the satellite's spatial geometry distribution and the positioning error closely related to the satellite's elevation angle and signal-to-noise ratio,so that the selected satellite subset with the minimum ES-WGDOP can achieve the high precision.Finally,the effectiveness and superiority of ES-WGDOP are verified by experiments.(2)Based on ES-WGDOP criterion,a satellite selection method based on ACO with polarized feedback(ACO-PF)is proposed.Firstly,satellite selection is described as a combinatorial optimization problem,and ES-WGDOP is defined as the criterion for satellite selection.Then the Ant Colony Optimization(ACO)algorithm is applied to solve the problem,and the polarized feedback mechanism is introduced to improve the convergence speed of the algorithm.Meanwhile,disturbance factor is designed to improve the global searching ability of the algorithm.In the experiment,Taguchi's method is used to optimize the parameters of ACO-PF.The experimental results show that ACO-PF algorithm can select the satellite combination with high accuracy,and its convergence speed is50% faster than the basic ACO algorithm.In addition,the ES-WGDOP value of ACO-PF result is usually 0.065 smaller than that of ACO.In this dissertation,the evolutionary algorithm ACO is introduced to solve the problem of satellite selection.Two improvements are proposed for the basic ACO algorithm,i.e.polarized feedback mechanism and disturbance factor,which improve the convergence speed and global searching ability of the algorithm.Thus the optimal satellite subset can be selected in the effective period.This dissertation focuses on the criteria and methods of navigation satellite selection,which has certain reference value and significance.