The Application Research Of GPS/SINS Intergrated Navigation System In The Homing Missiles

The Strap-down Inertial Navigation System (SINS) has the advantage of being independent of outside information.Not only could it calculate the position and velocity of the carrier,but it also can provide the information of attitudes. As well as,it has superior short-term error performance,data refresh rate,stability and interference immunity.However,But the SINS suffers from time-dependent error growth which causes a drift,therefore,SINS is inaccurate exceedingly when it works independently chronically.Global Positioning System (GPS) could provide high precision navigation information all time, taking advantage of the radio signal transmited by the satellites.But, the radio signal may be interrupted by external interference(the shelter from obstacles,for example),resulting of position interrupt,furthermore,the influence of the motion stress of missile to tracking loop of GPS receiver leads to losing lock of the tracking loop possibly,and GPS receiver not working.GPS/SINS integrated navigation system overcomes the shortcoming of standalone system,having the performances of high continuity,high reliability and high precision.This thesis mainly studies GPS/SINS integrated navigation system,which aims to Simulate and analyze the GPS/SINS Integrated Navigation Method in the guidance, navigation and control system of the Homing Missiles.First of all, the article describes the project background and value,as well as the both here and abroad development of integrated navigation system,and studies the fundamental operational principle of SINS and GPS based on the coordinate system used in GPS and SINS,and then,the error sources of SINS and GPS are analysed.Afterwards,the algorithms of information fusion of GPS/SINS integrated navigation system are analysed systematically.Based on the error equation of GPS and SINS,the mathematical models of GPS/SINS loosely integrated navigation and GPS/SINS tightly integrated navigation are derived.Finally,GPS/SINS loosely and tightly integrated navigation algorithm are simulated digitally,and the results of simulation demonstrate the validity of the systems:GPS/SINS loosely integrated navigation system could restrain time-dependent error growth of SINS;UKF could provide much higher precision than EKF;the performances of GPS/SINS tightly integrated navigation system is rather better than that of GPS/SINS loosely integrated navigation system.