Recently, we have been using wireless communication in various fields, which is essential to our social and business activity, e.g, broadcast and mobile communication operated from Medium Frequency to Ultra High Frequency (UHF) bands. On the other hand Biological effects due to radio wave exposure are depends on frequency, thermal effects are dominant in high frequency region higher than about 100 kHz. Furthermore, whole-body resonance phenomena arise in VHF band (30-300MHz) when the component of electric field is parallel to the direction of human body's height and the wavelength is about twice the height to human body near 80 MHz. In addition, ground plane was regarded as a perfect electric conductor, while the actual ground plane is lossy medium. In order to model semi-infinite ground, the PML condition which matches lossy ground is used. But, the huge computer resources are required, because, PML needs many additional variables. In this study, an efficient numerical modeling of lossy ground plane for FDTD analysis of induced current is proposed. The proposed method uses Surface Impedance Boundary Condition (SIBC). In this paper, we calculate the induced current of the metal wire standing on the realistic ground plane, and from results, it was shown that the proposed method was effective to model semi-infinite ground.
