Measurement and characterization on a human body communication channel

Wireless body area network (WBAN) has drawn more and more interests in recent years. As one alternative communication scheme for WBAN, human body communication (HBC) uses human body as the communication medium and it provides better performance for communication security, spectrum efficiency, power consumption, and electromagnetic compatibility. The aims of this paper are to measure and characterize a capacitive HBC channel and to build simple models for it. Measurements have been carried out for different electrode positions and different body shapes. The results show that the path-loss of HBC channel is a function of frequency and it needs to be modeled by separated frequency intervals. A general model is proposed for the path-loss for different scenarios and the model parameters are extracted by fitting methods. The impact of electrode positions on the path-loss is analyzed. To describe the dispersion effects in HBC channel, the coherent bandwidth and delay spread of HBC channels in different scenarios are also extracted from measured data. These results aim at providing references for the design and deployment of HBC systems.