抄録
It is difficult to get an enough clearance for measurements of reflection coefficient of materials in long wavelength region. In this paper, a method for measuring reflection coefficient of materials set in the Frenel region is examined by analytical and experimental investigations. For a metal sheet, a good agreement obtained between the analysis by the physical optics and the finite differential time domain methods, and experimental result. Experiments using three kinds of wave absorbers were made in VHF range. Although there are some variance in reflection coefficient data of wave absorbers, it is considered that the experimental results show reasonable values.