Enhanced Compact RF Energy Harvesting System Using Two-Port Network of Antenna

This letter presents a method to enhance a compact RF energy harvesting (RFEH) system using a two-port network of an antenna. Typically, RFEH rectennas, comprising an antenna and a rectifier, are assembled after designing independently, making performance evaluation challenging due to the antenna’s one-port configuration. By adapting the antenna to a two-port network, direct measurements of $S_{11}$ and conversion efficiency were enabled. A compact RFEH system operating at 0.9 GHz was implemented, and experimental results demonstrated that the proposed method improved efficiency through optimized matching circuit adjustments.