Optimization Strategy of Navigation Star Selection for Doppler Velocity of the Star (DVS) Aided SINS Integrated Navigation

Doppler velocity of star (DVS)-aided strap-down inertial navigation system (SINS)-integrated navigation (SINS/DVS) is an effective method for correcting spacecraft velocity errors, but its navigation accuracy is significantly affected by the geometric distribution of navigation stars. To solve this problem, the effect of star geometry on the transmission of the measurement errors of DVS is studied, and the relationship between the geometric distribution of stars and spacecraft velocity error is derived based on the measurement model. The results show that velocity error is negative correlated with geometric distribution. Then, a star optimization strategy based on geometric distribution is proposed, and the calculation of the optimization index k is given. To verify the effectiveness of the newly proposed optimization strategy based on k, the performance of SINS/DVS-integrated navigation under a variety of navigation star groups is evaluated. The results show that the navigation error decreases with increasing k. When k is 0.4758, the velocity error is only 10.39% of that when k is 0.0021. Thus, k can be used as an evaluation index for optimizing the navigation stars of SINS/DVS-integrated navigation.