Input impedance analysis of wearable antenna and its experimental study with real human body

Human body communication has received a lot of attention as a promising wireless technology for Body area network. In Human body communication system, High frequency signal is excited in human body through a wearable antenna. Therefore, it is important to investigate the input impedance characteristics of the antennas considering an effect of human body. In this paper, we studied the input impedance characteristics of antenna worn on the wrist under the dry/wet skin conditions. Moreover, experiment with a prototype wearable antenna and real human body was performed in the frequency range of 1 to 100 MHz. The results showed that moisture condition of the skin and differences among individuals had great effect on the input impedance in the low frequency range. However, analytical and experimental results showed the same tendency in whole frequency range. This means a validity of the FDTD simulation using detailed human arm model.