Far‐field Wireless Power Transmission for Biomedical Application

Chapter 8 embarks on an exploration of far‐field wireless power transmission (WPT) specific to biomedical applications. Starting with an introduction, the chapter elucidates the principles of far‐field EM coupling, including its power transfer efficiency, link design methodologies, and the challenges faced, alongside potential solutions. A pivotal section follows, detailing the development of enhanced far‐field WPT links for implantable devices, with emphasis on safety, implantable rectenna designs, and methods to amplify received power. Furthermore, solutions to common issues such as WPT antenna misalignment are presented, introducing a novel antenna alignment method leveraging intermodulation. The underlying operation mechanisms, miniaturized IMD rectenna designs, and NRIC link establishment are thoroughly discussed. The chapter provides practical insights through extensive measurements and discussions, including rectifier circuit designs and integration solutions. Concluding with experimental validation of the methods presented, the chapter offers a comprehensive view of advancements in far‐field WPT for biomedical applications.