Measurement-based analysis of the throughput-power level trade-off with modulated multisine signals in a SWIPT system

Abstract

Simultaneous wireless information and power transfer (SWIPT) has gained interest, especially due to its applicability in the world of Internet of Things. For pure wireless power transfer (WPT), multisine signals have already been shown to increase RF-to-DC power conversion efficiency (PCE) at the receiver which is key in WPT research. In a SWIPT system where the waveforms are modulated for information transfer, however, we expect the modulation scheme to impact both data transmission quality and WPT subsystem efficiency. This paper quantifies by means of an experimental study the impact of QAM and PSK modulated multisine signals, on the power and data transfer efficiency of a SWIPT system, taking into account the often neglected transmitter distortion. Error vector magnitude (EVM) is used as figure of merit for the impact of data transfer efficiency, output voltage ripple for the modulation's impact on WPT.