Simulation of ISAR Imaging of Ships with Multipath Effects

Multipath effects are investigated on inverse synthetic aperture radar (ISAR) image reconstruction of ships with rectilinear motion in different sea state. First, the generalized problems of multipath propagation in radar application are formulated. After a brief review of ISAR imaging principles, multipath propagation effects on ISAR imaging are theoretically analyzed and the point spread function (PSF) is defined, two artifacts with different intensities and shifts in ISAR generated images are introduced by multipath effects, moreover, range-Doppler imaging algorithms are used to give a more clear and direct explanation to the range and cross-range shift of these two artifacts. Finally, the theoretical analyses are validated by simulation of ISAR imaging of ships with rectilinear motion in different sea state, indistinct and distinct multipath influenced ship images are generated and compared to corresponding ones without multipath effects.