Experimental Validation of Surface Roughness Effects on EffectiveConductivity and Related Applications

This paper presents an experimental comparison between calculated and measured effective conductivities of copper foils subjected to different surface processing techniques. A Fabry–Perot open resonator is employed to determine the frequency-dependent effective conductivity. The measured results are compared with theoretical surface impedance values predicted by the Gradient Model, demonstrating strong agreement between experiment and theory. The proposed approach is further applied to extract the complex permittivity of prepreg materials and to characterize striplines incorporating multiple rough conductor surfaces.