On Secure Wireless Sensor Networks With Cooperative Energy Harvesting Relaying

Abstract

In this paper, we investigate the physical layer security (PLS) of a wireless sensor network (WSN) that consists of a base station (BS), multiple sensor nodes (SNs), and multiple energy-limited relays (ERs) in the presence of a passive eavesdropper (EAV). We adopt a time-switching/power-splitting (TSPS) mechanism for information transmission. The communication protocol is divided into two phases. The purpose of the first phase is to decode information, and energy harvesting (EH) is performed in accordance with the TSPS protocol. The purpose of the second phase is to transmit information to multiple destinations using the amplify-and-forward (AF) technique. In this study, we introduce a multirelay cooperative scheme (MRCS) to improve the secrecy performance. We derive analytical expressions for the secrecy outage probability (SOP) of the MRCS and that of the noncooperative relay scheme (NCRS) by using the statistical characteristics of the signal-to-noise ratio (SNR). Specifically, we propose an optimal relay selection scheme to guarantee the security of the system for the MRCS. In addition, Monte Carlo simulation results are presented to confirm the accuracy of our analysis based on simulations of the secrecy performance under various system parameters, such as the positions and number of ERs, the EH time, and the EH efficiency coefficients. Finally, the simulation results show that the secrecy performance of our MRCS is higher than that of the NCRS and the traditional cooperative relay scheme (TCRS).INDEX TERMS Energy harvesting, cooperative relay, time-switching/power-splitting, physical layer security.

System Performance Analysis for an Energy Harvesting IoT System Using a DF/AF UAV-Enabled Relay with Downlink NOMA under Nakagami-m Fading

“…As described in [ 47 ], at , the received power is divided into two streams, with for information processing and for EH (the APS ratio in Section III.C). Thus, the signal received at is written as follows: where , is the transmit power of B , and is additive white Gaussian noise (AWGN) [ 21 , 48 ]. Thus, the energy harvested at can be expressed as follows [ 49 , 50 , 51 ]: where is the EH efficiency coefficient, which depends on the rectification .…”

“…As described in [ 47 ], at , the received power is divided into two streams, with for information processing and for EH (the APS ratio in Section III.C). Thus, the signal received at is written as follows: where , is the transmit power of B , and is additive white Gaussian noise (AWGN) [ 21 , 48 ].…”

“…In this subsection, the throughput for each ID in the delay-limited mode is investigated. Suppose that the source transmits signals to the IDs at a fixed rate; thus, the throughput is mainly determined by the OP [ 20 , 48 ]. The throughput for each ID is given by …”

“…where g BU n =ĝ BU n + e BU n , P B is the transmit power of B, and n U n ∼ CN (0, N 0 ) is additive white Gaussian noise (AWGN) [21,48].…”

Optimal Multi-User Computation Offloading Strategy for Wireless Powered Sensor Networks

“…From the aspect of the way to harvest energy from wireless signals, it can be also divided into two categories. Generally speaking, there are two representative protocols for simultaneous wireless information and power transfer systems: 1) time switching protocol [11]; and 2) power splitting protocol [12]- [15]. For power splitting, the received signal at each antenna is splited into two separate streams with difference power levels for energy harvester and information decoder.…”