Mechanical and electromagnetic behavior of fabricated hybrid composite sandwich radome with a new optimized frequency-selective surface

Abstract A multidisciplinary design procedure was presented to fabricate hybrid composite sandwich (HCS) panels used in radomes based on conducting several mechanical and electromagnetic experiments. Accordingly, six specimens made of E-glass/aramid/polyester face sheets with different stacking sequences and polyvinyl chloride foam core were prepared using the vacuum-assisted resin transfer molding process. Afterward, three-point bending and low-velocity impact tests were performed and several mechanical characteristics were reported for specimens. Besides, electromagnetic wave transmission performance of the HCSs was experimentally and numerically determined. The accuracy of the simulated results was confirmed by free-space measurement method. The most efficient design of the hybrid stacking sequence was subsequently found by implementing the complex proportional assessment method and considering the mechanical and electromagnetic characteristics together with the moisture resistance of the specimens. Eventually, a new embedded frequency-selective surface (FSS) was designed for the radome using a genetic algorithm to maintain the transmission rate in the desired band at the order of higher than 90 percent. The comparison of the new FSS performance with conventional FSSs in the literature exhibited that the present optimization procedure not only achieves the maximum transmission at the resonance frequency but also enhances the transmission loss outside of the desired frequency band.