High resolution imaging experiment on differential synthetic aperture ladar

Using a tunable fiber laser of 1 550 nm wavelength, a high resolution imaging differential synthetic aperture ladar(DSAL) was set up in the laboratory. DSAL imaging experiments were carried out using a cooperative target at distance of 1.85 m. The phase history data (PHD) of the target returns were reconstructed and high resolution synthetic aperture images were generated by straightforwardly following standard DSAL image formation theory. High resolution DSAL images at various azimuth moving conditions were given in detail. Experimental data show that using the reconstructed PHD by DSAL technique, much better focused images can be produced, which demonstrates that the DSAL technique can robustly remove the common phase errors in the PHD. Moreover, DSAL images with various azimuth moving conditions show that even if the azimuth speed is 30% longer or shorter than its ideal value, the DSAL images are all well or at least acceptably focused, which means that a DSAL system is possibly well adaptive to the variation of its azimuth speed.