Research On MEMS-INS/GNSS Integrated Navigation System

MEMS-INS/GNSS integrated navigation system has the characteristics of small volume,low cost,high precision,good dynamic performance and strong anti-interference ability,so it has a very broad application prospects.In this paper,a set of embedded MEMS-INS/GNSS integrated navigation system is designed and its related technologies are studied.The main research contents include the following aspects:Firstly,according to the error characteristics of the micro inertial measurement unit,the error model is established and its performance is analyzed.For the deterministic error,the influence of the commonly used calibration method and six position calibration method on the error compensation is studied,at the same time,aiming at the problem of G value sensitive error,a calibration method based on the 16 position of the G sensitivity coefficient is proposed,the results show that the method can effectively reduce the influence of the measurement error caused by the acceleration on the gyroscope and improve the output precision of the micro inertial measurement unit.Secondly,the random error is studied using the method of wavelet threshold denoising method for denoising the Gyroscope Random error.In addition,the Allan variance method is used to analyze and identify the random error of the gyroscope at different sampling frequencies.The results show that the sampling error can be reduced effectively.Then,the GNSS positioning and direction finding algorithm is studied.Aiming at the defect that the output direction of MEMS-INS is not accurate,this paper proposes the algorithm of double difference carrier phase to solve the baseline vector,and the vector based attitude determination algorithm based on QUEST.In addition,the GNSS positioning and direction finding simulation platform is built and the related algorithms are verified.Finally,the state equation and observation equation of MEMS-INS/GNSS integrated navigation system are established,and the robust adaptive Calman filter is designed according to the complex and changeable motion state.On the basis of theoretical analysis and research,the design scheme of MEMS-INS/GNSS integrated navigation system is put forward.Finally,the performance of the whole system is analyzed and the effectiveness of the navigation algorithm is verified.