基于星载高低轨的单通道动目标检测技术

合成孔径雷达成像应用于观察包含运动目标的地面场景,特别是在对运动目标观察时间长的情况下,图像会产生由于距离徙动和多普勒频谱展宽引起的运动目标偏移。为了消除这些影响,本文提出一种适应于星载高低轨平台协作模式下对动目标进行检测成像的算法。距离徙动包括运动范围内的距离走动和距离弯曲可以通过广义keystone变换校正。然后,通过估计和补偿相位误差和折叠因子项,可以提高运动目标的分辨率。针对地面场景中的杂波,我们通过子孔径对消的方法进行抑制。该算法的有效性通过仿真结果进行验证。通过将广义keystone方法与子孔径对消方法结合,可以有效地对消静止目标杂波,从而更好的对动目标进行检测成像。 

Single-channel Based on High low Orbit Moving Target Detection Technology

When synthetic aperture radar (SAR) imaging is applied to observe ground scene containing a moving target, the imagery of moving target will be typically smeared due to range cell migration and Doppler spectrum broadening caused by the target motions, especially for the accelerating targets within a long observation time. To eliminate these effects, a novel imaging algorithm using cooperative between SAR under high-orbit and low-orbit satellites is proposed. The range migration including range walk and range curvature within the coherent integration period has been corrected via the third order keystone transform. Then, by estimating and compensating the phase errors and the fold factor terms, the target’s resolution is improved and the motion parameters are correctly estimated. The effectiveness of the proposed algorithm is demonstrated by simulations. By combining the generalized keystone method with the subaperture cancellation method, the stationary target clutter can be effectively cancelled, and the moving target can be detected more effectively.