Experimental Study of the Impact of Waveforms on the Efficiency of RF-to-DC Conversion Using a Classical Voltage Doubler Circuit

The present work is devoted to the study of the impact of various waveforms on the efficiency of RF-to-DC conversion in a classical voltage doubler circuit used in wireless power transfer (WPT) systems. The analysis of RF-to-DC conversion efficiency is based on the results of experiments in laboratory conditions. Unlicensed sub-gigahertz ISM bands are used for power transmission. Five different waveforms are examined: single carrier, multi-tone with a high PAPR level, multi-tone with a low PAPR level, chaotic signal and band-limited noise. The impact of the PAPR level, bandwidth and average input power levels on the efficiency of RF-to-DC conversion and the output voltage is analyzed. Moreover, this analysis is done for different load conditions of the voltage doubler circuit.