中文摘要：

捷联式成像导引头的光学探测基准随弹体姿态运动而动态变化，其目标图像的运动形式呈现复杂的非线性时变特性，传统扩展卡尔曼滤波（EKF）方法难以有效地针对目标运动模型进行波门设置及视线估计。为此，本文首先建立了以目标机动在惯性成像坐标系内的投影为输入，弹体姿态信息作为时变参数的目标帧间运动模型，并在此基础上提出了一种新的相关跟踪算法。该算法通过应用中心差分卡尔曼滤波（CDKF）理论有效解决了成像跟踪中的波门设置问题，提高了目标位置的估值精度，同时提出一种改进的变尺寸模板更新策略，抑制了目标图像的形变和模板漂移对匹配精度的影响，进一步提高了系统的跟踪的精度，并通过仿真验证了算法的良好跟踪性能。

英文摘要：

It is difficult that gate setting and target line-of-sight estimation are performed effectively by the traditional extended Kalman filter （EKF） according to a target motion model, because the optical detection base of strap-down imaging seeker changes with missile atlitude and its target imaging motion model presents nonlinear and time varying characteristics. To solve the mentioned above problem, the frame interval target motion model in the field of view of the seeker was established by taking the target maneuvering proiection in inertial imaging coordinate system and the missile attitude as the input and the time-varying parameters respectively. A novel image correlation tracking algorithm was pro- posed by the central difference Kalman filter （CDKF） used for gate setting and precise target position estimating, and the improved template update strategy used for overcoming the influences of target size variety and template drifting on matching accuracy to improve the systematic tracking accuracy. The simulated results show that the algorithm has a good tracking performance.