基于SQP算法的SAR成像导引头三维弹道优化

3D Trajectory Optimization of the SAR Imaging Seeker Based on SQP

弹载SAR平台轨迹的设计是研究弹载SAR成像算法的前提。为了在满足SAR成像条件的同时降低导弹打击时间,需要对SAR成像导引头的弹道进行优化。该问题属于非线性最优控制问题,本文采用序列二次规划(SQP)优化算法进行求解。首先以波束驻留时间最小为指标函数,导弹俯仰、偏航加速度为优化变量,建立了SAR成像导引头三维弹道优化模型,模型的约束包括SAR成像约束、过载约束和导弹飞行高度约束。然后,将原最优控制问题进行参数化,转换成非线性规划问题,利用SQP算法进行求解。参数化时,离散节点越多,得到的非线性规划问题规模越大,求解速度就越慢。仿真结果表明,SQP算法能够有效解决SAR成像导引头三维弹道优化问题,得到的解满足模型约束。

Trajectory design of the missile-borne SAR platform is the basis of the SAR imaging algorithm research. In order to decrease missile attacking time while satisfying the SAR imaging conditions, the SAR imaging seeker＇s trajectory needs to be optimized. This problem belongs to the nonlinear optimal control problem, and the sequential quadratic programming （SQP） optimization algorithm is used to slove it. Firstly, a 3D trajectory optimization model of the SAR imaging seeker is constructed. The contraints include the SAR imaging constraint, be overload contraint and the attitude eontraint. Furthermore, the original optimal control problem is transformed into a nonlinear programming problem, and then it is solved by the SQP algorithm. The more discreted nodes are, the biger the nonlinear programming problem scale is and the longer the solving time is. The simulation results show that, the SQP algorithm can effectively solve the trajectory optimization of the SAR seeker, and its solution satisfies all the model constraints.