Single Sideband Modulation Based Phase-coded Continuous Wave Inverse Synthetic Aperture Ladar Demonstration and Outdoor Experiment

Inverse synthetic aperture LADAR(ISAL) is a coherent imaging technology whose resolution is independent of the target distance. Compared with traditional linear frequency modulation scheme, phase-coded ISAL can refer to the methods in communication to reduce noise interference or compensate the carrier phase error. In this paper, a novel single sideband modulation based phased coded continuous-wave ISAL system is proposed and experimentally demonstrated. The spectral efficiency of the new system is twice that of the traditional system, resulting in twice the utilization of echo energy. In addition, the use of continuous wave modulation improves anti-noise capability and imaging quality. Imaging results with azimuth resolution of 1.51cm are obtained by two 4cm aperture diameter telescopes at the distance of 7km, achieved about twenty times higher than conventional real aperture imaging system.