Investigation on layover imaging in synthetic aperture ladar

Abstract

Due to the short laser wavelength, almost all practical targets are rough. Surface elevations in rough targets will result in layovers in synthetic aperture ladar (SAL). High resolution SAL image with layovers will be different from the target picture taken by incoherent tools as digital camera. To investigate the layovers in SAL image, a simplified mathematical model is built by optics diffraction theory and a laboratory SAL is setup using 1550 nm tunable laser source. Layovers in SAL images, in both theoretical simulation and experimental demonstration, are carefully observed. Detailed results on various targets are illustrated.

Keywords

synthetic aperture ladar (SAL) / rough target / layover / simulation / demonstration

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Acknowledgements

This work, initially sponsored by the National High Technology Research and Development Program of China (863 Program) (No. 2007AA12Z107) in 2007, is currently funded by National Natural Science Foundation of China (Grant No. 61178071).We greatly appreciate the help on SAR signal processing by vice Prof. Chang Liu in the Institute of Electronics, Chinese Academy of Sciences.

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg