Bistatic SAR simulation of ships in marine environments via EM scattering models

Synthetic aperture radar (SAR) plays an important role in remote sensing and target detection and identification of the terrain and marine environments. Compared with a monostatic SAR, a bistatic SAR can observe the scene from different directions by adjusting the position of transmitter and receiver, therefore, the simulation and analyses of bistatic SAR images of ships in marine environments can provide methods and means for feature understanding, detection and recognition of noncooperative targets, which is of great significance in target detection and recognition. For this purpose, based on the facet-based simplified small slope approximation (FBS-SSA) with geometrical optics and physical optics (GO/PO) hybrid method, this paper proposes a simulation method for bistatic SAR of a composite ship-ocean scene, and SAR images of maritime ships are simulated. The effects of ship orientation, coordinates of the transmitter and the receiver, polarization, sea state on radar images are analyzed. The results indicate that the bistatic angles, polarization and ship orientations have effects on SAR images. Therefore, SAR image features from different angles can be obtained by changing the radar angle, which benefits the recognition of ships in marine environments. In addition, shadow features in SAR images can also serve as an auxiliary mean for ship recognition.