Method for calculating the transmission loss of a radio-wave-shielding wall

Radiowave-shielding walls and floors made entirely of high-dielectric-loss material are being developed. It is necessary to determine the theoretical shielding characteristics of a shielding wall that requires a certain thickness. However it has previously been impossible to easily analyze walls composed of several layers and reinforcing meshes by an impedance method. Using equivalent distributed constant circuits and equivalent two-port networks, the authors have analyzed the characteristics of a radio-wave-shielding wall having an arbitrary number of material layers to an arbitrary polarization and radio frequency wave. As a result, they have derived expressions for theoretically calculating radio wave transmission loss of a wall. This paper describes the analytical method and a calculation example of a shielding wall developed by the authors´ company.