Space Targets Tracking Algorithm Based on Improved State Equation with Universal Variable Updating

To address the issues of poor tracking accuracy, complex operation, and numerous restrictive conditions in the progress of spaced-based target tracking, a cubature Kalman filter based on improved state equation with universal variable updating (UVUCKF) is proposed in this paper. By analyzing the relationship between orbital elements and motion state and combining it with the operating characteristics of low-orbit satellites, an auxiliary variable is introduced to help calculate satellite flight time. Through the calculation of flight time, the state information of satellite can be predicted at a given future time. Then, the states of the cubature points are updated in the cubature Kalman filter by using the improved satellite state equation with universal variable updating, which realizes the real-time tracking of the space target. Experimental results demonstrate that the tracking errors of space-based maneuvering targets remain stable at approximately 12 m for a distance of 40 km. The tracking algorithm not only enhances real-time calculations but also significantly improves the tracking accuracy of space-based targets.