Error of test parameters in the trajectory correction te chnology is too large.Real-time and security can not meet the accuracy require ments of the current situation.Proposed extended hybrid Kalman filter to estima te the projectile parameters of the three states

including the relative speed i n air

altitude and trajectory angle.State model of the Kalman filter system an d measurement model of axial acceleration measurements as observed quantity were established.IMU measurement data was filtered and processed to get the traject ory correction information with the smaller error and meeting the real-time and safety requirements.The simulation results show that filter is adjusted and te sted by the analog data

and the estimation performance of relative velocity is good.