本文针对地面运动目标成像问题,提出了基于平流层飞艇平台的稀疏阵列MIMO(Multiple-Input Multiple-Output)雷达的成像方法。该方法首先利用MIMO雷达阵列对观测场景进行空间并行采样获取其散射信息,其次由于两次脉冲回波信号中的运动目标信息不同而地杂波(或静止地物)信息相同,因此利用一次相消技术抑制回波信号中的地杂波分量。然后基于观测场景中运动目标的稀疏特性,将压缩感知理论引入到对运动目标重建过程中。该方法可有效避免地面运动目标成像时的地杂波干扰和运动补偿问题,同时采用稀疏阵列可大幅减少天线阵元个数,从而降低对飞艇平台的要求和系统成本,便于工程应用。最后利用仿真实验验证了该方法的有效性和可行性。
In this paper,an imaging method of ground moving targets based on stratosphere airship MIMO radar with sparse array is proposed.Firstly,the scattering information of the observed scene is obtained by the spatial parallel sampling procedure with the antenna array of MIMO radar.Secondly,because the information of the moving targets and the ground clutter is different in the two impulse echo signals,the one-order canceller method can be utilized to filter out the ground clutter.Then,basing on the moving targets in the observed scene are sparse,the Compressed Sensing theory is introduced into the reconstructing process.Imaging of ground moving targets by this method could avoid the ground clutter interference and the problem of motion compensation,and meanwhile the numbers of antenna is reduced dramatically by adopting the sparse array,which could decrease the demand of airship and the cost of the imaging system to be of advantage to engineering practice.Finally,the effectiveness and feasibility of this imaging method is validated by the simulative results.