A Comprehensive Analysis of Wi-Fi Energy Harvesting Rectenna System

This work presents the design and simulation of a 2.45 GHz full-wave bridge rectifier for RF (radio frequency) energy harvesting at low-power input conditions and preliminary work on defining an associated Figure of Merit (FOM). The performance of two Schottky diodes, HSMS2850 and SMS7630, is evaluated at -5 dBm and -15 dBm, achieving maximum Power Conversion Efficiencies (PCE) of 57% and 33%, respectively, and reflection coefficient S11 values below -30 dB. A theoretical analysis was conducted to calculate rectifier efficiency, which aligned with simulation results, providing a deeper understanding of system performance. A layout was developed, considering microstrip line and SMA connector effects, to prepare for future laboratory measurements offering insights into real-world performance. Additionally, a double-voltage rectifier was simulated, achieving PCE values of 41% and 66% at similar input power levels, furthermore various CMOS-based rectifier topologies reached PCE values of 69% at -5 dBm and 43.6% at -26 dBm. These findings provide a promising result and a comparison across different topologies and technologies. Finally, preparatory work on defining Figure of Merit FOM for RF energy harvester rectennas is introduced, using data analysis techniques, expert knowledge, and Principal Component Analysis (PCA) to establish a standardized framework for evaluating and benchmarking RF energy harvesters.