Enhancing Wireless Information and Power Transfer by Exploiting Multi-Antenna Techniques

TL;DR

This paper reviews how multi-antenna techniques can improve wireless information and power transfer by addressing challenges like channel fading, security, and efficiency tradeoffs, through parameter optimization and protocol design.

Contribution

It provides a comprehensive tutorial on multi-antenna based WIPT techniques, focusing on optimizing tradeoffs for short- and long-distance transfer using specific multi-antenna methods.

Findings

Multi-antenna techniques enhance WIPT performance.

Parameter optimization improves energy and spectral efficiency.

Simulation validates the effectiveness of proposed schemes.

Abstract

This paper reviews emerging wireless information and power transfer (WIPT) technique with an emphasis on its performance enhancement employing multi-antenna techniques. Compared to traditional wireless information transmission, WIPT faces numerous challenges. First, it is more susceptible to channel fading and path loss, resulting in a much shorter power transfer distance. Second, it gives rise to the issue on how to balance spectral efficiency for information transmission and energy efficiency for power transfer in order to obtain an optimal tradeoff. Third, there exists a security issue for information transmission in order to improve power transfer efficiency. In this context, multi-antenna techniques, e.g., energy beamforming, are introduced to solve these problems by exploiting spatial degree of freedom. This article provides a tutorial on various aspects of multi-antenna based WIPT techniques, with a focus on tackling the challenges by parameter optimization and protocol design. In particular, we investigate the WIPT tradeoffs based on two typical multi-antenna techniques, namely limited feedback multi-antenna technique for short-distance transfer and large-scale multiple-input multiple-output (LS-MIMO, also known as massive MIMO) technique for long-distance transfer. Finally, simulation results validate the effectiveness of the proposed schemes.