Comparison of Galvanic and Capacitive Coupled Intrabody Communication Channel by using Isolation Transformer

Intrabody communication is an emerging technology that uses human tissue as a data transmission channel. This study experimentally investigates wearable galvanic and capacitive-coupling-based intrabody communication channels. The performance of different coupling mechanisms was compared by assessing the communication channel behavior using a tissue model. Experimental measurements were conducted with chicken breast tissue in the frequency range of 100 kHz to 1 MHz. Additionally, the effect of electrical isolation using isolation transformers, known as baluns, was studied to mitigate common-mode noise. Results indicated that the fluctuation of the channel gain in the frequency ranges between 100 kHz - 400 kHz occurred with the usage of baluns. A high-pass behavior was observed beyond 400 kHz with the termination of balun at P1 and P2, separately. Channel gain results exhibit flat behavior after 400 kHz, which permits a simpler system design. Additionally, the capacitive coupling technique demonstrated superior performance compared to the galvanic coupling method.