Investigations of Electrical Size Effects on Radar Cross Section for Orthogonally Distorted Corner Reflectors

In this paper, distorting effects of increasing electrical dimensions of triangular trihedral, circular trihedral and octahedral corner reflectors on radar cross section (RCS) are investigated by simulation and experimental studies. RCS measurements with respect to azimuth angle of a circular octahedral corner reflector have been successfully verified by using different simulation techniques such as Method of Moments (MoM), MLFMM, SBR and transient. Electrically large triangle and octahedral corner reflectors are compared to small ones in terms of wavelength through the simulations, in order to explain dependence of RCS reduction on the size of the reflectors for a given geometrical deviation from orthogonality. It's been shown that RCS performance with respect to both azimuth angle and frequency of a reflector with electrically large size is extremely sensitive to small deviation angles in orthogonal corners. On the other hand, RCS is less sensitive to small deviations of the orthogonal angles for reflector sizes in excess of a few wavelengths.