Resistance Compression Dual-Band Differential CMOS RF Energy Harvester Under Modulated Signal Excitation

This paper proposes a resistance compression dual-band differential CMOS RF energy harvester for harvesting power at dual frequencies. The use of resistance compression dual-band matching network minimizes the sensitivity of the RF-DC converter for the variation in the input power and the rectifier load. The proposed system can work at 914 MHz and 2.4 GHz for arbitrary complex impedance simultaneously. The design is fabricated in a standard CMOS 0.18 μm technology and provides a regulated output voltage of 1 V. The cumulative efficiency in the presence of two frequencies shows an improvement of 14.2% with concern to single frequency (914 MHz at -14 dBm). Also maintains the efficiency of >20% for the input power range of -16 ~0 dBm. Also studied and analysed the implication of Wi-Fi bandwidth (72 MHz), OFDM modulation, and 64-QAM modulation on the efficiency and sensitivity of the system concerning continuous input signal. Observed the improvement in the efficiency with the peak-to-average power ratio.