Research On Critical Technoloiogies In Integreated Navigation Algorithms

SINS/GPS integrated navigation is an important technology which has increasing extensive usage in military, commercial and civil field. It takes advantages of both inertial and GPS navigation system to provide high-precision navigation service. Initial alignment and information fusion serve as its two critical parts.For the initial alignment part, we simulated the widely used methods, including KF, EKF and UKF, and analyzed the precision, efficiency and robustness in this application. Furthermore, a BP neural net assisted EKF algorithm was proposed to be used in initial alignment of integrated navigation. Specifically, the BP neural net was applied for estimating the noise in EKF model. This method makes the EKF algorithm close to matching the UKF in initial alignment. Under some circumstance, e.g., a well trained neural net model, the NN assisted EFK method even defeats the UKF method in precision and robustness.For the information fusion part, we simulated the circumstance that GPS system gets stuck and used the BP neural net mode to assists the inertial navigation system. BP neural net is just a barely-qualified method in this situation so we proposed a batter one to support the inertial navigation system when meeting the outage of GPS system, and that is the Radial Basic Function neural net.