【摘要】 为减小单星测频定位的误差,提出一种融合初值校准与二阶逼近的单星测频定位算法。该算法在卫星接收信号多普勒频移为零的时间点,通过测距获得卫星到定位目标的距离信息,利用距离信息修正轨道平面与定位目标的几何关系,为初值的选取提供校准手段;将校准的初值代入含二阶级数的定位方程泰勒展开式,通过较少次数的迭代得到定位目标的真实位置,从而降低定位的算法复杂度,提高定位精度。仿真结果表明,所提出的算法与多普勒单星定位算法相比,迭代次数和定位误差大幅度减小,其实现简单、计算量少、误差小,在单星定位研究领域具有较高的理论价值和实用价值。更多还原

【Abstract】 In order to reduce the error of single-satellite localization from frequency measurements,an algorithm of single-satellite localization from frequency measurements,which combines the initial value calibration and the second order approximation,was proposed. The algorithm obtains distance information from the satellite to the localization target at the time point when the Doppler frequency shift of the satellite receiving signal is zero,and then corrects the geometric relationship between the orbit plane and the localization target by using the distance information,thus it provides a calibration method for the selection of the initial value. By substituting the calibrated initial value into Taylor’ s expansion of the localization equation containing the second order numbers,the real position of the localization target was obtained through fewer number of iteration,thus reducing the complexity of localization algorithm and improving the localization accuracy. The simulation results indicate that compared with the Doppler single-satellite localization algorithm,the iteration times and the localization error of the proposed algorithm are reduced substantially. The algorithm is easy to implement,low in computation and small in error,and has high theoretical and practical value in the field of single-satellite localization research.更多还原