Analysis and measurement of electric field distribution in body area network based on active quasi-electrostatic field

Body area network based on active quasielectrostatic field could be a promising solution for next generation wearable networks. In this paper, electric field distribution of BAN is analyzed by FEA simulation and quantitatively measured using real human body. A continuous sine wave of 10Vp-p and 1MHz is fed on the transmitter plates placed near left wrist of human body. Two kinds of transmitter are used in the experiments. One is a function generator, and the other is a small circuit board which can be used directly as a valid transmitter in BAN. The receiver plates have been placed in different positions on human body with variable distances to skin. Simulation results and measurement results of peak-to-peak voltage on receiver plates are compared. Results show that most part of the electric field is concentrated around the plates of the transmitter, while other part of electric field distributes evenly along surface of human body and degrades rapidly when leaving human body. The receive signal amplitude when using function generator is much higher than that when using the transmitter circuit board. The voltage on the receiver plates increases rapidly when touching the transmit electrode. It means that human body changes the distribution and extends the range of electric field produced by the transmitter. By virtue of the particular electrostatic field distribution, unobtrusive pervasive sensing and data communication can be implemented naturally and safely by people's daily actions.