Power efficiency and optimum load formulas on RF rectifiers featuring flow-angle equations

This paper considers three pairs of circuit schemes for RF rectification. Given finite available power from RF source and load resistance, we formulate DC output power and efficiency of each scheme. Resultant formulas find that load-to-source resistance ratio R/r dominates the circuit performance. Maximum efficiency reaches 81.1% at R/r = 1 for single-diode half wave rectifiers. It also reaches 92.3% for multiple-diode full wave ones at R/r = 1.347 in bridge with capacitor, 0.742 in bridge with inductor, 5.389 in double-voltage, and 0.1854 in double-current topologies.