Research Of The Deep Integration Of GPS/SINS Navigation System

GPS (Global Positioning System) satellite navigation system, strap-down inertial navigation system (SINS) each has its traits. Integrating GPS, SINS and complementing their performance is important scheme for highly autonomous and accurate navigation. Deep integrated GPS/SINS system based on pseudo-range and pseudo-range rate is more accurate, robust, jam-resistant than the loosely coupled model based on position and velocity. The thesis mainly research the filter model of deep coupled navigation system .Based on this model, SINS is used to assist position calculation of GPS when less than 4 satellites in sight. In the meanwhile, SINS is used to determine the multipath effect and eliminate the multipath effect to reach high precision.Firstly, a brief review of the development of navigation system and the characteristics of integrated navigation system, then the present situation of deep integrated system and the theory of the data fusion of integrated navigation system are discussed. The principles, error models and characteristics of different navigation systems, including Strap-down Inertial Navigation System (SINS), Global Positioning System (GPS) are also introduced. Then the principle, reason of multi-path effect and some normal ways to eliminate it are also introduced.Secondly, error model of deep integrated navigation system is build based on the error equation of GPS and SINS and the simulation system of deep integrated GPS/SINS system is designed. Then, the data fusion technology of deep integrated navigation system is researched. Discrete Kalman Filter, Adaptive Filter and Unscented Kalman Filter (UKF) are used in the system. After the comparison of different filter models, the best precision filter model is used in the deep integrated navigation system below. Thirdly, SINS is used to assist the position calculation of GPS when less than 4 satellites insight. Experiment results show that the deep integrated GPS/SINS system can realize high precision positioning in a short time.Finally, SINS is used to determine the multi-path effect .Pseudo-range and pseudo-range rate can be calculated by SINS. The satellite which suffered from multi-path effect can be determined by judging the reasonable range of pseudo-range and pseudo-range rate. Then, the satellite suffered from multi-path effect is not used in the position calculation. Experiment results shows that the method can effectively eliminate the multi-path effect and get high precision position information.