Comprehensive measurements on body channel characteristics of Human Body Communication

Human Body Communication (HBC) is regarded as a novel transmission technology for Artificial Intelligent (AI) society. It is important to measure and analysis body channel characteristics and the results are significant for Integrated Circuit (IC) design of HBC. This paper proposed an improving electrode configuration which was used to couple signals to human body with capacitive coupling type. The body channel characteristics in frequency domain, in time domain, and with different digital modulation were taken into sight systemically by Vector Network Analyzer (VNA), Vector Signal Generator (VSG), Digital Signal Analyzer (DSA), Arbitrary Function Generator (AFG) and Oscilloscope. The bandpass filtering characteristic of body channel was measured, and the center frequency is about 30 MHz. The capacitive characteristic of body channel was also measured, and the capacitive characteristic disappears gradually with frequency increasing. Besides, the spectrum profiles of body channel characteristics with Frequency Shift Keying (FSK) and On-Off Keying (OOK) modulation after 20 cm HBC were measured. Error Vector Multitude (EVM) was measured with different bits Quadrature Amplitude Modulation (QAM) after 20 cm HBC.