针对外辐射源信号特点，考虑相位误差对成像性能的不良影响，提出了基于压缩感知联合稀疏孔径自聚焦的无源雷达成像方法. 利用不同载频外辐射源信号在不同转角下的点扩散函数构造稀疏传感矩阵的每个列向量，并利用lp 范数法将带约束条件的强散射点增强问题转换为无约束的最优问题求解，同时建立关于相位误差的最优化问题，通过准牛顿法求解相位误差增量，从而实现目标成像与相位误差的联合估计. 仿真结果表明，与子孔径综合无源雷达成像相比，该方法无需大的目标累积转角，同时在存在相位误差时仍可获得较好的成像效果.
In this paper, passive multistatic radar imaging based on compressed sensing joint sparse aperture autofocus is presented. The method uses a point spread function of the different opportunistic illuminator to construct a reasonable sparse basis matrix, and turns the point-enhanced problem into an optimization problem by using the lp norm method. Meanwhile an optimization problem in terms of phase error is established. The quasi-Newton method with a phase error update scheme is used to obtain the increment of phase error. The simulation shows good performance of this method at small rotating angle and in the presence of phase error.
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