Simple Dual Band Rectifier Based on Diplexer for Ambient RF Energy Harvesting Application

In this paper, we present a novel configuration of dual band rectifier for RF energy harvesting application. Unlike traditional dual band rectifiers which employ only one rectifier with the ability to operate at two different frequencies, the proposed design consists of two separated rectifiers, each operates at a distinct frequency, thus simplify the design process significantly. The two rectifiers are connected to the multiband receiving antenna via a microstrip diplexer which carries out the task of distributing the collected power at each frequency to the corresponding rectifier. Numerical simulation and measurement are carried out to evaluate the design, showing a simulated AC - DC conversion efficiency of 52% at 1.8 GHz and 46% at 2.6 GHz and a measured efficiency around 40% for both frequencies under -10 dBm low input power.