捷联导引头目标视线角速率重构方法研究

Line-of-Sight Angle Rate Reconstruction for Strap-down Seeker

捷联导引头测量信息中耦合有弹体姿态信息不能直接被比例导引所用。实现了从捷联导引头和弹体角速率信息中重构出目标视线角速率,并运用四阶龙格库塔法建立离散模型,避免迭代发散。捷联导引头大的瞬时视场带来大的背景噪声,任何用于重构系统的测量信息噪声都会反映到重构出的目标视线角速率中去。针对系统模型参数噪声与状态噪声并存的问题,从模型中分离开参数和状态,设计了JointUKF和DualUKF提取目标视线信息,简化了系统噪声模型,降低滤波器对噪声标定不准确的敏感性。通过弹目拦截仿真验证了目标视线角速率重构方法的正确性,验证了采用离散方法的合理性,验证了设计的滤波器能有效提取目标视线角速率。

Strap- down seeker＇s detecting information is coupled with missile attitude information, hence it can＇ t be used for proportional navigation directly. The methods of reconstructing inertial line - of - sight （LOS） rate in strap - down seeker are investigated which only use output information of strap - down seeker and rate gyros. Forth - order Runge - Kutta is proposed to construct discrete model to reduce truncation error and avoid iterative divergence. Large instantaneous field of view will cause great background noise and any inaccurate metrical information used by the reconstructing system would be reflected to the final LOS, thus, filter is required. After separating the parameter and system state from the model, Joint Unscented Kalman Filter （Joint UKF ） and Dual Unscented Kalman Filter （ Dual UKF） are applied for LOS reconstruction filter coupled with simplified system noise. Both filters are less sensitive than general UKF to noise demarcating. The results of simulation validate the rationality and efficiency of the methods used in this paper.