Unified Design Method of Filters for Different Measurement Phases in Space Relative Navigation Tasks

In spacecraft relative navigation, as the relative distance changes, the output varies with different measurement devices. For traditional filtering methods, different filters need to be switched when the measurement output changes, which reduces the computational efficiency. Considering this problem, a simplified converted measurement Kalman filter (SCMKF) is designed to construct a unified filter. The proposed unified filter simplifies the calculation of the measurement noise covariance matrix, based on the analysis on the factors affecting measurement noise and the accuracy of measurement device. Compared to the traditional filter, the proposed unified filter decreases the computational complexity significantly on the premise of ensuring the calculation accuracy.