Multi-Hop MIMO Relaying Based on Simultaneous Wireless Information and Power Transfer

Kwadwo Boateng Ofori-Amanfo,Kyoung-Jae Lee,Derek Kwaku Pobi Asiedu,Roger Kwao Ahiadormey

doi:10.1109/access.2021.3122375

Abstract

This paper studies a multiple-input and multiple-output (MIMO) multi-hop decode-and-forward (DF) relaying wireless network. Communication between a source node and a destination node is aided via multi-hop relays with simultaneous wireless information and power transfer (SWIPT). We investigate the separate application of both power splitting (PS) and time splitting (TS) based SWIPT relaying protocols in our system model. The performances of the two are then compared and analyzed. The SWIPT protocol enables the current relay to harvest energy from the immediately preceding relay node, to reliably forward the information signals between the source and the destination. We aim to minimize the transmit power at the source under the end-to-end system throughput constraint by optimizing either PS or TS ratios at each relay node. For that, the global solutions for the ratios of either PS or TS are attained via convex optimization techniques. A closed-form solution was reached for the SWIPT PS approach. However, the SWIPT TS approach is achieved via an iterative algorithm. Also, we propose a simple routing algorithm based on Dijkstra’s algorithm for our proposed DF-SWIPT multi-hop system. Finally, we compare the proposed PS and TS ratio schemes to their corresponding fixed PS and TS ratio schemes, in terms of source power resource consumption, computational complexity, and overhead analysis. It is found that the PS outperforms the TS, owing to the higher computationally demands of the TS.

Highlights

A wireless network consists of several wireless nodes, gateways, and a central system, communicating with each other by routing schemes [1]–[3]
Based on the energy minimization solutions, we propose centralized and distributed methods by which each relay node’s power splitting (PS)/time splitting (TS) ratio can be determined in real-world wireless networks
SIMULATION RESULTS we evaluate the performance of the DF relaying multi-hop wireless network

Summary

Introduction

A wireless network consists of several wireless nodes, gateways, and a central system, communicating with each other by routing schemes [1]–[3]. The main purpose of relays is to facilitate information forwarding and an increase in communication system throughput [4], [5]. In carrying out these tasks they depend on their limited resources to aid communication between two nodes [4], [5]. WPT implementation in a cellular communication system is accomplished through two main approaches , i.e., wireless powered communication networks (WPCN) and simultaneous wireless information and power transfer (SWIPT) [4], [5], [7]. SWIPT involves both wireless information transfer (WIT) and WPT being used concurrently [4], [5]. To implement SWIPT, the two main techniques of time splitting (TS) and power splitting (PS) are utilized in wireless systems [4], [5], [8]

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Results

Conclusion