A Comparative Study of Conventional Rectifier Topologies for Low Power RF Energy Harvesting

A comparative study among the four commonly used rectifier topologies in literature was presented with the aim of indicating which one yields the maximum RF-to-DC power conversion efficiency for low power RF energy harvesting. For a fair comparison, source-pull simulations were conducted to extract the optimal diode input impedance and to further provide the maximized efficiency for a given RF input power, frequency, and load value. It was shown that, independently of frequency, a single diode topology leads to a better efficiency at low RF powers (< −15 dBm), whereas, a doubler topology provides a larger power dynamics.