Wireless-powered relays in cooperative communications: Time-switching relaying protocols and throughput analysis

Date

Authors

Nasir, Ali
Kennedy, Rodney
Zhou, Xiangyun
Durrani, Salman

Journal Title

Journal ISSN

Volume Title

Publisher

Institute of Electrical and Electronics Engineers (IEEE)

Abstract

We consider wireless-powered amplify-and-forward and decode-and-forward relaying in cooperative communications, where an energy constrained relay node first harvests energy through the received radio-frequency signal from the source and then uses the harvested energy to forward the source information to the destination node. We propose time-switching based energy harvesting (EH) and information transmission (IT) protocols with two modes of EH at the relay. For continuous time EH, the EH time can be any percentage of the total transmission block time. For discrete time EH, the whole transmission block is either used for EH or IT. The proposed protocols are attractive because they do not require channel state information at the transmitter side and enable relay transmission with preset fixed transmission power. We derive analytical expressions of the achievable throughput for the proposed protocols. The derived expressions are verified by comparison with simulations and allow the system performance to be determined as a function of the system parameters. Finally, we show that the proposed protocols outperform the existing fixed time duration EH protocols in the literature, since they intelligently track the level of the harvested energy to switch between EH and IT in an online fashion, allowing efficient use of resources.

Description

Keywords

Citation

Source

IEEE Transactions on Communications

Type

Journal article

Book Title

Entity type

Access Statement

Open Access

License Rights

Restricted until

Downloads

File
Description
Author/s Accepted Manuscript (AAM) / Post-print