Waveforms and End-to-End Efficiency in RF Wireless Power Transfer Using Digital Radio Transmitter

We study radio frequency (RF) wireless power transfer (WPT) using a digital transmitter for applications where alternative analog transmit circuits are impractical. An important parameter assessing the viability of an RF WPT system is its end-to-end efficiency. In this regard, we present prototype test bed comprising software-defined (SDR) and energy-harvesting receiver with low resistive load; employing SDR makes our research meaningful simultaneous information (SWIPT). analyze effect clipping nonlinear amplification at on multisine waveforms. Our experiments suggest that when direct current (dc) input constant, high peak-to-average ratio (PAPR) multisines unsuitable over flat-fading channel, due to their average radiated power. The results indicate efficiency positively correlated waveform it reduces increasing PAPR. Consequently, modulations, such as phase shift keying (PSK) quadrature amplitude modulation (QAM), yield better than multisines. Moreover, PSK QAM signals invariant transmission bit rate. in-depth analysis reveals lower Furthermore, impact reflecting surface assess quality by evaluating error vector magnitude (EVM) SWIPT. Overall, experimental observations EVM that, while fixed dc power, baseband signal most suitable SWIPT large, among signals.