Implant-to-implant wireless networking with metamaterial textiles
Xi Tian, Qihang Zeng, Selman A. Kurt, Renee R. Li, Dat T. Nguyen, Ze Xiong, Zhipeng Li, Xin Yang, Xiao Xiao, Changsheng Wu, Benjamin C. K. Tee, Denys Nikolayev, Christopher J. Charles, John S. Ho
Abstract
Implanted bioelectronic devices can form distributed networks capable of sensing health conditions and delivering therapy throughout the body. Current clinically-used approaches for wireless communication, however, do not support direct networking between implants because of signal losses from absorption and reflection by the body. As a result, existing examples of such networks rely on an external relay device that needs to be periodically recharged and constitutes a single point of failure. Here, we demonstrate direct implant-to-implant wireless networking at the scale of the human body using metamaterial textiles. The textiles facilitate non-radiative propagation of radio-frequency signals along the surface of the body, passively amplifying the received signal strength by more than three orders of magnitude (>30 dB) compared to without the textile. Using a porcine model, we demonstrate closed-loop control of the heart rate by wirelessly networking a loop recorder and a vagus nerve stimulator at more than 40 cm distance. Our work establishes a wireless technology to directly network body-integrated devices for precise and adaptive bioelectronic therapies.