Design and manufacture of a dual-functional exterior wall structure for 1.1-5 GHz electromagnetic radiation absorption

In order to solve the increasing serious electromagnetic (EM) radiation pollution, this paper presents a dual-functional exterior wall structure for EM radiation protection. The EM wave absorption properties of the exterior wall structure were investigated in 1.1-5 GHz using arch reflecting method, and results indicate that the optimal absorption property with effective bandwidth below −10 dB reaches 3.7 GHz (1.1-4.8 GHz) can be obtained by the combination of periodic structure and multi-layer structure. The destructive interference, dielectric loss of carbon black (CB), and multiple reflection and scattering of expanded perlites (EP) are the main EM wave absorption mechanisms. The absorption peaks of reflection loss curves are caused by destructive interference, and effective bandwidth is determined by the dielectric loss capacity of CB. Moreover, the multiple reflection and scattering of EP particles play a major role in EM wave absorption. It is expected that the devised exterior wall structure has great potentials in EM radiation protection.