Nine-axis MEMS-IMU and GNSS integrated navigation method in magnetic anomaly field interference environment

The invention relates to a nine-axis MEMS-IMU and GNSS integrated navigation method in a magnetic anomaly field interference environment. The method comprises the following steps: S1, initializing a system navigation state; s2, carrying out navigation calculation by using the nine-axis MEMS-IMU (Micro Electro Mechanical System-Inertial Measurement Unit) data and the GNSS data; step S3, establishing an MEMS-IMU and GNSS integrated navigation model under the magnetic anomaly interference environment; s4, carrying out state calculation on the MEMS-IMU and GNSS integrated navigation model by utilizing a Kalman filtering algorithm; and S5, completing the state calculation and correction of the integrated navigation model. According to the method, the magnetic anomaly vector and the combined navigation state quantity are both used as unknown quantities for estimation, so that the problem of course misalignment of a traditional combined navigation system of the same type under magnetic anomaly interference is solved