Radar simulation using the shooting and bouncing ray technique

This paper is based on the design and development of an electromagnetic simulation package used for predicting the radar cross section (RCS) of partially open cavities. In the RCS analysis of objects such as aircrafts or ships, the cavity structures (such as air-vents and jet outlets) play a major role to the contribution of the reflected radar. Thus cavities can be seen as having a certain stealthiness-coefficient to them. By manipulating their physical shape one can reduce the amount of RCS backscatter reflected. The simulation process applies the Shooting-and-Bouncing-Ray (SBR) method in conjunction with electromagnetic field theory. A vector effective height (VEH), of the antenna used, is introduced to take into account the polarization coupling effects resulting from each reflection within the cavity. The final gain of the power received can be determined by the incoherent summation of all the contributing rays. To verify the validity of the simulation, a comparison is made to the RCS scan of a rectangular cavity. The results show a close correlation between the simulated and measured environments. Furthermore, an illustration of RCS optimization is shown by modifying the rectangular cavities dimensions and comparing the two results.