自适应加权质心算法在高精度星点定位中的应用

Application of Adaptive Weighted Centroid Algorithm in High Accuracy Star Localization

为实现空间飞行器在高目标星等、像移和光学系统像差等因素影响下的高精度星点定位,提出了一种自适应加权质心细分定位算法。基于最大似然估计推导、建立数学模型并进行仿真实验。结果表明,与质心法、加权质心法及高斯拟合法等传统星点定位算法相比,提出的算法定位精度提高了50%以上,且具有良好的收敛速度,经过5次迭代后,质心定位误差相对较稳定,可以满足实际应用中对实时性的要求。

An adaptive weighted centroid localization algorithm is proposed to solve the problems caused compositely by the high magnitude stars,the image motion and the aberration of optical system in high accuracy star localization.A mathematical model based on the maximum likelihood estimation is derived and built to perform numerical simulations.The results show that the localization accuracy of the algorithm proposed is increased by over 50%compared with that of the traditional star localization algorithms such as centroid method,weighted centroid method and Gaussian fitting method.The proposed algorithm has good convergence rate,and the centroid location error is relatively stable after five iterations,which can meet the real-time requirement in practical applications.