Shared wireless link codesign for implantable device with farfield wireless power transfer Implantable devices are nowadays commonly used in medicine. However, these devices run mostly on batteries, leading to a finite lifetime due to the required battery replacement. Since wireless power is almost available everywhere, a suitable way to avoid battery replacement would be to recharge them wirelessly using wireless power transfer. As these implantable devices mostly feature a single antenna, it must be shared to communicate and to receive power. In this way, a circuit that turns off the communication blocks and other circuits while recharging is needed. In this paper, an RF CMOS frontend with farfield wireless powering for implantable devices with a power management module will be presented. This circuit is able to control the frontend circuits when the battery reaches predefined operating voltages.

Design and validation of a sixantenna WPT system with tracking capabilites for biomedical devices Reliable powering of implantable medical devices is a key requirement for the development of eversosmall sensors and actuators. The difficulty of this task becomes even greater when the device is meant to travel inside the human body. This paper presents a 2 GHz RF WPT system capable of tracking an implantable device and maximizing the amount of power transferred to it along its path. Measurements and simulations were performed to validate the system, and the use of tracking increased the amount of available power for the implant along its path in all the studied points comparatively to the scenario where no tracking was used. This technology presents itself as a promising stepping stone towards batteryless implantable medical devices.