The defects of the traditional strapdown inertial navigation algorithms become well acknowledged and the enhanced traditional algorithms have been quite recently proposed trying to mitigate both theoretical and algorithmic defects. In this paper, the analytical accuracy evaluation of both the traditional algorithms and the enhanced algorithms is investigated, against the true reference for the first time enabled by the functional iteration approach having provable convergence. The analyses by the help of MATLAB Symbolic Toolbox show that the resultant error orders of all algorithms under investigation are consistent with those in the existing literatures, and yet the effect of the enhanced algorithms is marginal. Numerical results agree with analyses that the enhanced algorithms have marginal accuracy improvement over the traditional algorithms, while the functional iteration approach possesses significant accuracy superiority even in sustained lowly dynamic conditions.

翻译：传统捷联惯性导航算法的缺陷已得到广泛认可，近期提出的增强传统算法试图从理论和算法层面弥补这些不足。本文首次利用具有可证明收敛性的函数迭代方法，以真实参考值为基准，对传统算法和增强算法进行了解析精度评估。借助MATLAB符号工具箱的分析表明，所研究的所有算法的误差阶数与现有文献一致，但增强算法的效果有限。数值结果与理论分析吻合，即增强算法相比传统算法的精度提升甚微，而函数迭代方法即使在持续低动态条件下仍具有显著的精度优势。