Spacecraft orbit rendezvous base on square root unscented Kalman filter

Concerning the automatic orbit rendezvous of the non-cooperative targets, this paper studies the one all measuring data getting form radars. C-W equation and observing equation are inferenced to present the relative motion of the two satellites. According to the method square root filter could overcome Kalman filtering divergence, square root unscented Kalman filter is proposed to estimate the relative state of the pursuing spacecraft and the target. Compared with extend Kalman filter(EKF), this algorithm needn't calculate Jacobian matrix, but more easier to convergence. Simulation result shows this algorithm sharply develops the filter's effect, enhances estimate precision.