Companding and Predistortion Techniques for Improved Efficiency and Performance in SWIPT

TL;DR

This paper explores how combining companding and digital predistortion techniques can enhance efficiency and performance in SWIPT systems by mitigating non-linear effects and improving energy harvesting without compromising data transfer.

Contribution

It introduces a novel combined approach using companding and DPD to optimize PA operation and energy harvesting in SWIPT systems, with established design criteria.

Findings

Significant increase in power transfer efficiency with combined techniques

Enhanced energy harvesting performance without affecting data transfer

Effective mitigation of non-linear effects in SWIPT systems

Abstract

In this work, we analyze how the use of companding techniques, together with digital predistortion (DPD), can be leveraged to improve system efficiency and performance in simultaneous wireless information and power transfer (SWIPT) systems based on power splitting. By taking advantage of the benefits of each of these well-known techniques to mitigate non-linear effects due to power amplifier (PA) and energy harvesting (EH) operation, we illustrate how DPD and companding can be effectively combined to improve the EH efficiency while keeping unalterable the information transfer performance. We establish design criteria that allow the PA to operate in a higher efficiency region so that the reduction in peak-to-average power ratio over the transmitted signal is translated into an increase in the average radiated power and EH efficiency. The performance of DPD and companding techniques is evaluated in a number of scenarios, showing that a combination of both techniques allows to significantly increase the power transfer efficiency in SWIPT systems.