条带模式合成孔径激光雷达振动目标成像的计算与仿真

在光学波长的尺度上,几乎没有目标可被认为是静止的,因此,目标振动对合成孔径激光雷达(SAL)成像可能有较大影响。对此问题,基于衍射光学,建立了在目标作简谐振动的情况下,采用准单色光线性调频光源照明的条带模式SAL的成像数学方程,分析和讨论了目标振动参数对SAL成像的影响,并给出了若干数学仿真演示。结果表明,SAL成像对目标振动非常敏感,在距离方向上目标微小的振动可使SAL系统在方位向上产生一系列虚假像,严重影响SAL高分辨率成像的实现。

Calculations and Simulations on Vibrating Targets Imaging in Strip-Map Mode Synthetic Aperture Ladar

In optical wavelength scale, any targets can be hardly regarded as stationary. Therefore, target vibration may affect synthetic aperture ladar (SAL) imaging severely. To address this problem, the imaging mathematical equation of strip-map mode SAL, in which quasi-monochromatic chirp laser is used as the illumination source in the situation of target vibrating, is set up. Using this equation, the effection of the vibration parameters is analyzed and discussed, and some simulations for this are performed. The result shows that SAL imaging is extremely sensitive to the target vibration. Tiny target vibration in range may bring a series of false images in azimuth to the final SAL image and seriously affect the realization of a high resolution SAL imaging.