Analyzing Electro-Magnetic Wave Signal Characteristics for Intra-Body Communication Systems

In Wireless Body Area Networks (WBANs), body-attached devices communicate with each other to form services around the human body. To design WBANs, Intra-body Communication (IBC) uses electro-magnetic (EM) wave signals and utilizes the human body as the communication medium, rather than using the surrounding air with RF signals. IBC allows the air medium to be freely used by other services while offering WBAN services and shows lower energy consumption compared to RF-based nodes. In this work, we conducted a pair of experiments to obtain knowledge on the signal attenuation and signal propagation latency characteristics of EM waves on the human body. Our results show that the average attenuation observed from a human body was -27dB in a capacitively-coupled circuit and -36dB in galvanically-coupled circuit, and the propagation delay of EM waves on the human body was 0.94ns per cm. These findings can be further utilized to design more complex protocols for IBC networks.