Effect of Thickness and Conductivity on Electromagnetic Interference Shielding Effectiveness of Bio Composite Shields

Today’s fast growing wireless world faces one new type of problem, Electromagnetic (EM) pollution due to advancements and penetration of communication technologies. This disturbs the proper functioning of electronic devices due to EM Interference (EMI) and also harmful for human health at some extent. Therefore, EM Compatibility (EMC) becomes necessary for electronic devices. Another problem faced by the world, is environment pollution created by biomass waste. Researchers have shown very much interest in the fabrication of EMI shields made from Bio composite materials to minimize the effect of above mentioned two types of pollutions. The Bio composite shields can be made from blending and mixing of polymers, bio char and highly conductive nano fillers. The shielding effectiveness (SE) of Bio composite shields is mainly function of conductivity, thickness, dielectric properties of shield and frequency of EM waves incident on shield. The S-parameters of shield can be measured by standard waveguide method and shielding effectiveness can be calculated. This paper presents the simulations of S-parameters of shield using CST microwave studio simulator for the frequencies from 8 GHz to 12 GHz i.e. X band. The SE is calculated from S-parameters and effect of thickness and conductivity of shield on SE is analyzed and discussed.