Study On The Satellite Navigation Algorithm For Missile-borne Receiver Based On Muti-epoch Technology

With the continuous development of the global navigation satellite system,its implication for military applications is irreplaceable,especially missile-borne navigation systems,its use can not only improve the accuracy of hit and the efficiency of the damage,but also reduce the costs of experiments.This paper puts it as a background and takes some researches on how to reduce the time of first fix when satellite signals are recovered and improve the precision of positioning and velocity in the high dynamic case.The main contents are as following:1.According to the analysis of the satellite navigation fundamental and the main source of errors and their calibration model for the receiver,aimming at the problem that clock error is inevitable,the paper introduces a multi-epoch EMBET self-calibration technique,proposes an approach that use the technology to build the receiver clock error correction model,and takes a verifiable experiment.The result shows that this method is effective and has high accuracy,and can be carried out to estimate the receiver clock error in advance,compared with solving clock error using single epoch it can reduce the number of unknowns.2.In context of the receiver clock error having been corrected,the paper puts forward a method that leave out the frame synchronization based on the precision clock,and proposes a three-satellite area selected algorithm.Experiments show that the amount of calculation is greatly reduced by this method,which is saving a lot of time,and can select the ideal satellite to ensure positioning accuracy.Combination of both methods make the hot start-up time reduce to less than two seconds,which achieve the purpose of the fast positioning when satellite signals are recovered.3.It analysises the dynamics of particle trajectory and builds kinematics simulation model,proposes that add trajectory kinematics equations to Kalman filter to improve the precision of positioning and velocity under high dynamic,and how the size of the gain value of Kalman filter influence the accuracy of positioning and velocity is analyzed.4.It takes some comprehensive simulation experiments.Experimental results show that compared to the least square positioning algorithm,the method put forward by this paper can improve the positioning accuracy under high dynamic situations,and during the experiment it finds that the filter gain threshold set in order to inhibit the filter distortion affect the accuracy of velocity,the smaller the threshold,the higher the accuracy.