Input Power Range Extension Using Duty-Cycling and Granularity Reduction in a 5.8GHz RF Energy Harvester Dynamic Matching Circuit

Abstract

Using a continuous dynamic matching circuit in an RF energy harvester ensures the desired output voltage is achieved over the input power range. However, the minimum harvestable power level is limited by the power overhead of the continuous dynamic matching circuit. In order to reduce this power overhead, the processing and actuating block of the control system are duty-cycled. In addition, reducing the granularity or the number of the matching circuit sets lessens the power overhead needed for sensing, processing, and actuating. The RF energy harvester was implemented using an intermittent dynamic matching circuit to improve its input power sensitivity. By reducing the power overhead of the dynamic matching circuit, the RF energy harvester’s lower input power limit was extended from -7dBm to -20dBm.