An X-band conformal FSS with enhanced shielding effectiveness

A conformal frequency selective surface (FSS) with band stop property is described in this paper for X-band electromagnetic shielding applications. A thin polyimide is used as a substrate layer to develop the proposed FSS. The FSS proposed is a single-layer solution and is constructed using a modified octagonal loop element. Inductive stubs of definite length are added to the periphery of the modified octagonal loop to control the frequency and bandwidth characteristics of the FSS. The realised stopband bandwidth of the proposed FSS with reference Shielding Effectiveness (SE) of 15 dB is 40% with a centre frequency of 10 GHz. The FSS provides good polarisation stability with angular independent characteristics up to theta = 80 degrees. The proposed FSS has stable operating characteristics under both flat and bent conditions. The prototype of the Frequency Selective Surface is manufactured, and the theoretical results are validated using experiments. The performance of the FSS is compared with the state-of-the-art. The proposed FSS unit cell is a low-profile configuration making it a suitable candidate for electromagnetic shielding in military and warfare systems.