Home > Research > Publications & Outputs > Improving Secrecy Performance of a Wirelessly P...

Electronic data

  • czc_lucie_edits with eqns

    Accepted author manuscript, 406 KB, PDF document

    Available under license: CC BY: Creative Commons Attribution 4.0 International License

Links

Text available via DOI:

View graph of relations

Improving Secrecy Performance of a Wirelessly Powered network

Research output: Contribution to journalJournal article

Published
<mark>Journal publication date</mark>1/11/2017
<mark>Journal</mark>IEEE Transactions on Communications
Issue number11
Volume65
Number of pages13
Pages (from-to)4996-5008
Publication statusPublished
Early online date27/07/17
Original languageEnglish

Abstract

This paper considers the secrecy communication of a wirelessly powered network,
where an energy constrained legitimate transmitter (Alice) sends message to a legitimate receiver (Bob) with the energy harvested from a dedicated power beacon (PB), while an eavesdropper (Eve) intends to intercept the information. A simple time-switching protocol with a time-switching ratio $\alpha$ is used to supply power for the energy constrained legitimate transmitter. To improve the physical layer security,
we firstly propose a protocol that combines maximum ratio transmission (MRT) with zero-forcing (ZF) jamming for the case where Eve is passive in the network, so that Alice only has access to the channel state information (CSI) of Bob. Then we propose a protocol that uses a ZF transmitting strategy to minimize the signal-to-noise ratio (SNR) at Eve for the case where Eve is active in the network, so that Alice only has access to the partial CSI of Eve. Closed-form expressions and simple approximations of the connection outage probability and secrecy outage probability are derived for both protocols. Furthermore, the secrecy throughput as well as the diversity orders achieved by our proposed protocols are characterized and the optimal time-switching ratio $\alpha$ and power allocation coefficient $\beta$ for secrecy throughput maximization are derived in the high SNR regime. Finally, numerical results validate the effectiveness of the proposed schemes.