Joint Optical Wireless Power and Information Transfer to Implantable Electronic Devices Exploiting NIR Light

This paper proposes an application-oriented experimental setup for joint optical wireless power and information transfer for implantable electronic devices (IEDs) across thicker biological tissue up to 40 mm. This study aims to address stringent requirements relevant to future IEDs, i.e., secure wireless communication and extending battery lifespan. This novel approach considers near-infrared (NIR) light, a tissue-mimicking phantom to simulate the human soft tissue and a supercapacitor that acts as a secondary energy storage. This study is application-oriented and conducted in test beds based on commercial off-the-shelf (COTS) components containing an LED driver module, NIR LED (810 nm wavelength), a tiny photovoltaic (PV) cell (~6 cm² area), a photodetector amplifier (PDA), and a power management integrated circuit (PMIC). The PDA and a PV cell are used for data and power reception, respectively, forming a receiver to stimulate IEDs. The communication performance, as well as charging and discharging capabilities, are evaluated through experiments. Joint data and power transmission were also demonstrated by sending a high-definition image to the PDA while energy was harvested through the PV cell. This study contributes to innovating healthcare, opening avenues for future enhancements in the context of telemetry and wireless recharging applications across biological tissue. It is expected that IEDs can be improved not only in functionality and security but also in longevity with the help of an energy harvesting system at the receiver end.