基于未知地标被动观测的飞航导弹SINS俯仰姿态误差估计方法

针对飞航导弹单独使用时SINS存在姿态估计精度随时间降低的问题，提出了基于未知地标被动观测的SINS俯仰姿态误差估计方法。首先，根据飞航导弹中制导段飞行的特点，把SINS俯仰姿态误差估计问题转化为攻角估计问题。然后，在不改变导弹巡航路径的前提下，利用弹上成像导引头对视场内任意未知地标连续被动观测，分别提出了弹体坐标系和速度坐标系下的攻角估计方法，并分析了观测噪声对量测方程系数的影响。最后，利用平均去噪的思想对估计结果进行处理，提高了SINS俯仰姿态误差的估计精度。仿真结果表明：两种方法都能有效估计出飞航导弹SINS俯仰姿态量测误差。

A Pitch Attitude Error Estimation Method Based on Passive Observation to Unknown Feature Target for Cruise Missile SINS

In absence of other navigation systems, cruise missile SINS attitude error will cumulate continuously with time. A novel SINS pitch attitude error estimation method based on passive observation to unknown feature target is proposed in this paper. Firstly, the SINS pitch attitude error estimation problem is transformed into the attack angle estimation problem according to characters of cruise missile midcourse guidance. Then by use of passive observation to unknown feature target, two attack angle estimation methods are proposed respectively in body coordinate system and in velocity coordinate system separately without changing the cruise path of cruise missile. And the influence of observation noise is analyzed. Finally, Mean denoising approach is used to improve the estimation accuracy. Simulation results show that both the attack angle estimation method in body coordinate system and in velocity coordinate system are effective.