Vector Miss Distance Parameter Estimation Based on Direct Position Determination

The vector miss distance measurement (VMDM) plays a key role in the scoring system. In the traditional two-step method, the estimation accuracy of intermediate measurements is limited by the nonstationary characteristics of echoes present in the rendezvous process. To address this problem, an innovative vector miss distance parameter estimation method based on direct position determination (DPD) is proposed in this study. The proposed method can directly estimate vector miss distance parameters with higher accuracy from the echoes received, in which the intermediate measurements need not be estimated in advance. The closed-form expressions of the Cramér-Rao bound (CRB) for vector miss distance parameters are also derived. The simulation results show that the proposed method outperforms the traditional two-step method in terms of the estimation accuracy of vector miss distance parameters. Moreover, the proposed method is more robust to the high noise levels and inconsistency of the receiving channels. The experimental data further validated the efficiency of the proposed method.