A novel dual-band RF energy harvesting circuit with power management unit for low power applications

In this letter, a novel dual-band RF energy harvesting circuit (EHC) with power management unit (PMU) for low power applications is proposed, that can operate BQ25504 PMU of Texas Instruments for low input power applications. The proposed RF EHC has been investigated by mathematical analysis and optimization of variable conditions, such as the number of stages and load resistance for the low input power operation. Additionally, BQ25504 is used to boost the output voltage of RF EHC and battery charging. To verify the analysis, a novel dual-band RF EHC is designed and fabricated at 0.88 and 2.44 GHz. The measurement results show RF-DC conversion efficiency and output voltage of only dual-band RF EHC of 15% and 285 mV at -20 dBm/tone, respectively. Finally, the dual-band RF EHC connected BQ25504 achieves 3.2 V output voltage and 11% efficiency at -13 dBm/tone.