ANALYSIS OF FREQUENCY SELECTIVE SURFACES FOR RADAR ABSORBING MATERIALS

Abstract

In this dissertation analysis of different Frequency Selective Surfaces (FSS) for Radar Absorbing Materials (RAM) is described. The aim of analysis is to find the best FSS for a particular radar absorbing material. Matlab code was developed to analyze the different FSS and to select the FSS which gives best performance. To verify the simulation results, three ferrites were fabricated and three were taken from already prepared. Then five different FSS were implemented on ferrite coating. FSS unit cell parameters and ferrite coating thickness were optimized using Genetic Algorithm (GA). FSSs were fabricated on ferrite coating using photolithographic method follower by wet etching. Absorption was measured by Absorbing Testing Device (ATD). It was practically verified that Triple Square Loop FSS gives the best performance in comparison to single Square FSS, Double Square FSS, Cross Dipole FSS and Jerusalem Cross FSS. As. results obtained from simulation approximately absorption=21%. Further Triple square FSS was implemented on Cylinder and cone to observe its effect on Radar Cross Section (RCS), and up to 93% RCS reduction was observed in case of cylinder