Electric Field Distributions Generated by a Wearable Device Using Simplified Whole Human Body Models

In recent years, a communications system, the Body Area Network, which uses the human body as a transmission path has attracted attention, and there is increasing expectation that it will be used more widely. However, there are still several points on the signal transmission mechanism of using the human body in this way that remain to be clarified, and there has been little research into the interaction of electromagnetic waves and the human body. Therefore, we used the Finite Difference Time Domain (FDTD) method to calculate the Efield distributions around simple and realistic models of the whole human body in free space with a weareble device. Moreover, E-field calculations were carried out when the positions of the body were changed. Our results show that using the simple homogeneous whole human body model is valid for the E-field calculation, and the dominant component of the E-field is normal to the body/air interface in all the positions that the human body assumes in daily life. Furthermore, in the state where the human body is shunted to the Earth ground, it was shown clearly that the E-field distribution is not mostly different from when a body is floating in free space. It can be concluded that these results provide useful information in improving the design of wearable devices.