Waveform Optimization for Wireless Power Transfer with Nonlinear Energy Harvester Modeling

TL;DR

This paper introduces adaptive multisine waveforms optimized for nonlinear energy harvesters in wireless power transfer, significantly improving harvested power by integrating RF design with channel information.

Contribution

It develops novel waveform design methods based on posynomial maximization that account for non-linear energy harvester characteristics, advancing the state-of-the-art in waveform optimization.

Findings

Waveforms significantly increase harvested DC power.

Adaptive waveforms outperform fixed ones in simulations.

Design method effectively incorporates channel state information.

Abstract

Far-field Wireless Power Transfer (WPT) and Simultaneous Wireless Information and Power Transfer (SWIPT) have attracted significant attention in the RF and communication communities. Despite the rapid progress, the problem of waveform design to enhance the output DC power of wireless energy harvester has received limited attention so far. In this paper, we bridge communication and RF design and derive novel multisine waveforms for multi-antenna wireless power transfer. The waveforms are adaptive to the channel state information and result from a posynomial maximization problem that originates from the non-linearity of the energy harvester. They are shown through realistic simulations to provide significant gains (in terms of harvested DC power) over state-of-the-art waveforms under a fixed transmit power constraint.