合成孔径激光雷达(SAL)是合成孔径与激光雷达的结合体。由于SAL的工作波长较短,可以在短时间内实现高分辨率成像,近年来发展较快。但短波长也会带来其他问题,对于机载SAL,其波长比载机振动幅度小1~2个数量级,所以载机的振动会给回波带来较大的相位误差,传统的惯导系统很难达到激光波长级的定位精度,需要进行基于数据的自聚焦才能实现SAL成像。针对这一问题,提出一种利用最小熵自聚焦(MEA)和deramp结合的全孔径成像算法,并利用该算法对SAL实测数据进行了成像处理,成像结果证明了该算法的有效性。

Synthetic aperture ladar (SAL) is a combination of synthetic aperture and ladar, which has developed rapidly in recent years. Since the wavelength of the SAL is short, high-resolution imaging can be achieved in a short period of time. However, short wavelength also brings other problems. For airborne SAL, the wavelength is less than the vibration amplitude of the airplane by 1-2 order of magnitude, and the vibration of the airplane results in a great phase error to the echo. It is difficult for the inertial navigation system (INS) to achieve the positioning accuracy at the laser wavelength level, so the data-based self-focusing is necessary in SAL imaging. In this paper, a full aperture imaging algorithm based on minimum entropy autofocus (MEA) and deramp is proposed to process the SAL real data. The imaging results verify the effectiveness of the proposed algorithm.