SWIPT in mMIMO system with non-linear energy-harvesting terminals: protocol design and performance optimization

Kui Xu,Jie Liu,Wei Xie,Ming Zhang,Nan Sha,Lihua Chen

doi:10.1186/s13638-019-1378-4

Abstract

In this paper, we design the simultaneous wireless information and power transfer (SWIPT) protocol for massive multi-input multi-output (mMIMO) system with non-linear energy-harvesting (EH) terminals. In this system, the base station (BS) serves a set of uplink fixed half-duplex (HD) terminals with non-linear energy harvester. Considering the non-linearity of practical energy-harvesting circuits, we adopt the realistic non-linear EH model rather than the idealistic linear EH model. The proposed SWIPT protocol can be divided into two phases. The first phase is designed for terminals EH and downlink training. A beam domain energy beamforming method is employed for the wireless power transmission. In the second phase, the BS forms the two-layer receive beamformers for the reception of signals transmitted by terminals. In order to improve the spectral efficiency (SE) of the system, the BS transmit power- and time-switching ratios are optimized. Simulation results show the superiority of the proposed beam-domain SWIPT protocol on SE performance compared with the conventional mMIMO SWIPT protocols.

Highlights

With the rapid rise of the Internet of Things (IoT) industry [1], massive intelligent devices will be deployed in anywhere to monitor engineering structures, diagnose the physical condition of the patients, report the real-time traffic information, and so on
For the PS simultaneous wireless information and power transfer (SWIPT) receiver, the received radio frequency (RF) signal is split into two parts according to the PS ratio [13]; one portion is sent to the energy harvester, and the remainder is sent to the information decoder
In this paper, we propose a beam-domain SWIPT protocol for massive multiple-input multipleoutput (mMIMO) system with non-linear energy harvesting

Summary

Introduction

With the rapid rise of the Internet of Things (IoT) industry [1], massive intelligent devices will be deployed in anywhere to monitor engineering structures, diagnose the physical condition of the patients, report the real-time traffic information, and so on. The practical SWIPT receiver architecture can be mainly classified as time-switching (TS) and powersplitting (PS) [14] according to the signal partition method for EH and information decoding (ID). The TS SWIPT receiver alternates between EH and ID according to the TS ratio [15], and as a result, the received RF signal is first sent to the energy harvester and to the information decoder. For the PS SWIPT receiver, the received RF signal is split into two parts according to the PS ratio [13]; one portion is sent to the energy harvester, and the remainder is sent to the information decoder

Methods

Results

Conclusion