On-Chip 5&6-GHz RF Energy Harvesting System for Implantable Medical Devices

This paper presents a fully integrated CMOS front end for Radio frequency energy harvesting as a practical solution to power implanted medical devices within the human body. The system incorporates an on-chip tunable impedance matching network and a cross-coupled differential drive (CCDD) rectifier featuring a body biasing technique to enhance input sensitivity. The rectifiers are interconnected in a cross-coupled configuration, leading to reduced ON resistance and minimal reverse leakage current during forward and reverse-biased states, respectively. Also the rectifier output is regulated using Power on Reset, Bandgap Voltage Reference and Low Dropout Regulator blocks, which are designed to consume low power. These utilizing TSMC 0.18 μm CMOS technology, the RFEH front end is tailored for operation in the Wi-Fi 6 (5 GHz) and Wi-Fi 6E (6 GHz) frequency bands, achieving an enhanced sensitivity of -20 dBm at the 1.2-V output voltage. Overall this compact system finds potential applications in implantable medical devices.