Research On Key Technologies Of BDS/INS Deeply Integrated Navigation System In High Dynamic Environment

The Bei Dou satellite navigation system independently developed and operated by China provides a reliable way for our country's national defense and civil satellite navigation,and the inertial navigation system is a commonly used technology in carrier navigation and positioning.The research on high-performance BDS/INS integrated navigation system is of great significance to our country's military and civilian use,and it is conducive to the Bei Dou satellite navigation system to serve the world with better performance.High dynamic motion carriers such as airplanes and artillery shells require high-precision navigation and positioning.However,in the high dynamic environment,the integrated navigation accuracy of loosely and tightly integrated systems is affected by the degradation of receiver navigation performance.The deeply integrated navigation system can realize the mutual assistance of satellite and inertial navigation,thereby improving the navigation and positioning accuracy under high dynamic conditions.This paper studies the key technologies of BDS/INS deeply integrated navigation system in high dynamic environment,and the software platform of BDS/INS deeply integrated navigation system is built and verified by experiments.The main content of this paper is as follows:Firstly,the calculation algorithm of strapdown inertial navigation is described.High dynamic motion carriers such as airplanes and artillery shells will inevitably rotate and the rotation vector method can compensate for the non-commutability error of rotation.Aiming at the problem that multi-sample rotation vector algorithm will decrease the attitude update frequency,a second-optimized single-sample rotation vector attitude algorithm under angular rate input is proposed.On the basis of the traditional conic optimization method of error compensation coefficient,the error compensation coefficient of the period term is optimized twice.Experimental results show that the algorithm has high attitude resolution accuracy,and can keep the attitude update frequency as the sampling frequency of the inertial device.Then,the Bei Dou satellite signal is introduced and the signal acquisition and tracking methods are explained.The process of using satellite ephemeris to calculate the position and velocity of the satellite and using pseudorange and doppler frequency to calculate the position and velocity of the receiver is given.An experimental platform for simulator experiment and semi-physical experiment is built,a high dynamic motion trajectory is designed,and the performance of the Bei Dou scalar satellite software receiver developed based on the Matlab platform is verified by simulator experiment and semi-physical experiment respectively.Next,the vector tracking technology is researched.From the perspective of the loop structure,the advantages of the vector tracking loop compared to the scalar tracking loop are analyzed,and the system model of the vector receiver is analyzed.The navigation solution method based on the extended kalman filter and the method of using the navigation filter results and satellite ephemeris to generate the control variables of carrier loop and code loop are studied.The performance of the Bei Dou vector satellite software receiver developed based on the Matlab platform is verified by simulator experiments and semi-physical experiments respectively.Due to the navigation filter is used to control each satellite tracking loop,compared with the scalar receiver,the robustness and accuracy of the vector receiver are higher in the high dynamic environment.Finally,based on vector tracking and strapdown inertial navigation technology,the BDS/INS deeply integrated navigation system is researched.The principle and advantages of deeply integrated navigation are analyzed,the system model of deeply integrated navigation system is established,and the method of using inertial navigation information to control the satellite feedback loop of deeply integrated system is studied.The performance of the BDS/INS deeply integrated navigation system developed based on the Matlab platform is verified by simulator experiments and semi-physical experiments respectively.Due to the filtered and corrected inertial navigation information is used to control each satellite tracking loop,compared with scalar and vector receivers,deeply integrated navigation system has higher robustness and accuracy in the high dynamic environment.