This Letter gives the general construction of an enhanced self-heterodyne synthetic aperture imaging ladar (SAIL) system, and proposes the principle of image processing. A point target is reconstructed in the enhanced self-heterodyne SAIL as well as in down-looking SAIL experiments, and the achieved imaging resolution of the enhanced self-heterodyne SAIL is analyzed. The signal-to-noise ratio (SNR) of the point target final image in the enhanced self-heterodyne SAIL is higher than that in the down-looking SAIL. The enhanced self-heterodyne SAIL can improve the SNR of the target image in far-distance imaging, with practicality.

A static-mode synthetic aperture imaging ladar (SAIL) in which the target and carrying platform are kept still during the collection process is proposed and demonstrated. A target point of 0.5 mm×0.5 mm and a two-dimensional (2D) object are reconstructed in the experiments, in which an optical collimator with a focal length of 10 m is used to simulate the far-field condition. The achieved imaging resolution is in agreement with the theoretical design. The static-mode down-looking SAIL has the capability to eliminate the influence from the atmospheric turbulence and can be conveniently operated outdoors.