PAPR-Aware Waveform Design for Energy-Efficient MIMO-OFDM SWIPT

TL;DR

This paper develops a unified framework for PAPR-aware waveform design in MIMO-OFDM SWIPT systems, optimizing energy transfer and data throughput by balancing PAPR effects on power amplifiers and rectifiers.

Contribution

It introduces a novel analytical framework linking PAPR characteristics to energy harvesting and proposes a frequency-domain resource allocation strategy for MIMO-OFDM SWIPT.

Findings

Enhanced power amplifier efficiency and rectifier output.

Effective waveform adaptation improves energy transfer.

Validates approach through simulation results.

Abstract

Simultaneous wireless information and power transfer (SWIPT) critically depends on waveform design, which governs both reliable data delivery and efficient energy harvesting. Among waveform characteristics, the peak-to-average power ratio (PAPR) plays a pivotal role: low-PAPR signals improve power amplifier (PA) efficiency, while high-PAPR signals exploit rectifier nonlinearities to boost harvested energy. This duality makes PAPR a fundamental design challenge in SWIPT systems. To tackle this issue, we establish a unified analytical framework that characterizes the PAPR-dependent behaviors of both the PA and the rectifier, thereby revealing how waveform statistics determine end-to-end energy transfer efficiency. Building on this insight, we propose a frequency-domain resource allocation strategy for power-splitting SWIPT, where spectral segments are adaptively assigned to balance communication throughput with energy harvesting performance. Here, a key contribution is to extend SWIPT to MIMO-OFDM architectures. Despite concerns over excessive PAPR in large-scale antenna-subcarrier configurations, we demonstrate that appropriate waveform adaptation and resource optimization can transform MIMO-OFDM into an energy-efficient platform for joint data and power transfer. Finally, simulation results confirm significant improvements in PA efficiency, rectifier output, and overall energy transfer, thereby validating the practical benefits of the proposed approach.