复杂场景下基于压缩感知的目标电磁散射与成像

研究了处于复杂场景下目标的逆合成孔径雷达(ISAR)成像问题。首先,建立了目标与复杂环境的电磁散射模型,采用计算电磁学的方法仿真得到了目标的雷达回波数据,进而充分考虑了背景噪声对雷达成像质量的影响。研究发现,目标所处的复杂背景会降低ISAR对目标的成像质量。其次,为减小仿真雷达回波数据所需的计算量,提出采用基于压缩感知(CS)的方法来对该场景进行成像,从而极大降低电磁仿真的计算点数。通过实验发现,在CS成像中,采用数据点使用率为0.4时所得到的成像质量可达到采用转台成像质量的效果。因此,采用基于CS的成像方法,可极大降低目标与场景的电磁散射计算复杂度,使得处于真实复杂场景下的目标电磁仿真和ISAR成像研究切实可行。

Electromagnetic scattering and image processing of targets under complex environment based on compressive sensing method

The inverse synthetic aperture radar (ISAR) imaging of a target in a complex environment was studied in this paper. Firstly, the radar echo from the target underlying a complex environment has been simulated by using the computational electromagnetics, where the interactions from its environment have been taken into account. It was found that the imaging quality will be affected by the environment scattering. Secondly, a new simulation model based on the compressive sensing (CS) algorithm was proposed, which greatly reduces the computational costs of radar echo simulation. Corresponding experiments show that the imaging quality achieved with the data utilzation rate of 0.4 in CS model can reach the same level of traditional ISAR imaging. Therefore, this model can reconstruct the image by using fewer data points, which makes the electromagnetic simulation and ISAR imaging of target under complex environment possible.