Design And Simulation Of Ultra-Tightly Integrated Navigation System In High Dynamic Situation

With the emerging of high speed aircrafts, the increasing demanding of navigation systems has led to further development and researches on SINS/GPS integrated navigation systems in high dynamic situation. In general,SINS/GPS integrated navigation systems mostly base on technologies that GPS signals are applied for SINS error correction. In high dynamic situation, it may not work due to lose lock of GPS signals. SINS/GPS ultra-tightly integrated navigation systems, which applied inertial measurement aiding GPS tracking technique, might be one solution for the problem. This thesis introduces our researches on design and simulation of SINS/GPS ultra-tightly integrated navigation systems in high dynamic situation.Firstly, brief introductions to inertial navigation systems(INS), GPS, and ultra-tightly integrated navigation system have been given, including principles of INS and GPS, design of software GPS receiver, models and filters design of different integrated navigation systems. Simulation results show that the tightly integrated navigation system provides better precision in high dynamic situation.Secondly, design of SINS aiding carrier phase tracking loop of GPS receiver is described in detail. Affect of high dynamics on tracking loop has been discussed based on simulations. Then design of a novel adaptive tracking loop aided by SINS has been presented. Simulation results prove that the present tracking loop obtains much better performance on tracking high dynamic GPS signals comparing to common GPS receiver. The band width of loop also decreases dramatically which can improve the anti-noise performance. Furthermore, affect of inertial sensor precision is analyzed for sensor choices of SINS/GPS ultra-tightly integrated navigation system.Finally, a simulation system of ultra-tightly integrated navigation systems and high dynamic movement of aircrafts is developed, including high dynamic trajectory generator, SINS simulator, high dynamic middle frequency signal generator, software GPS receiver, filters, etc. The simulation system provides test platform for high dynamic environment and ultra-tightly integrated navigation system. A further study on the affect of observe matrix changing due to satellite signal failure and affect of GPS measurement precision are discussed based on the simulation results.The contribution of study in this thesis is to provide approaches for key techniques on design of SINS/GPS ultra-tightly integrated navigation system. The results can be applied in further study on implementation of SINS/GPS ultra-tightly integrated navigation system.