A Reconfigurable CMOS Rectifier for 905-MHz RF Energy Harvester with Omnidirectional Monopole Antenna

This article proposes a high-efficiency reconfigurable CMOS rectifier for radio-frequency (RF) energy harvesting. The rectifier has been fabricated in a $180-\mathrm{nm}$ CMOS technology. With the auxiliary transistors and substrate technique, working in 905 MHz, the proposed rectifier finally achieves a peak efficiency of 54% under $24-\mathrm{k} \Omega$ loading resistance with the power dynamic range (PDR) of 9.3 dB. Moreover, a $905-\mathrm{MHz}$ RF energy harvester with the proposed rectifier and a wide-band omnidirectional monopole antenna is designed. The proposed antenna bandwidth with $\left|S_{11}\right|\lt-10 \mathrm{~dB}$ is given by 900 MHz, and under the constant distance from transmit antenna to received antenna of 30 cm, the measured harvester output voltage reaches 1 V with -11.7 dBm received RF power.