In this paper, we study the physical layer security for simultaneous wireless information and power transfer (SWIPT)-based half-duplex (HD) decode-and-forward relaying system. We consider a system model including one transmitter that tries to transmit information to one receiver under the help of multiple relay users and in the presence of one eavesdropper that attempts to overhear the confidential information. More specifically, to investigate the secrecy performance, we derive closed-form expressions of outage probability (OP) and secrecy outage probability for dynamic power splitting-based relaying (DPSBR) and static power splitting-based relaying (SPSBR) schemes. Moreover, the lower bound of secrecy outage probability is obtained when the source's transmit power goes to infinity. The Monte Carlo simulations are given to corroborate the correctness of our mathematical analysis. It is observed from simulation results that the proposed DPSBR scheme outperforms the SPSBR-based schemes in terms of OP and SOP under the impact of different parameters on system performance.
In this paper, we study the physical layer security for simultaneous wireless information and power transfer (SWIPT)-based half-duplex (HD) decode-and-forward relaying system. We consider a system model including one transmitter that tries to transmit information to one receiver under the help of multiple relay users and in the presence of one eavesdropper that attempts to overhear the confidential information. More specifically, to investigate the secrecy performance, we derive closed-form expressions of outage probability (OP) and secrecy outage probability for dynamic power splitting-based relaying (DPSBR) and static power splitting-based relaying (SPSBR) schemes. Moreover, the lower bound of secrecy outage probability is obtained when the source's transmit power goes to infinity. The Monte Carlo simulations are given to corroborate the correctness of our mathematical analysis. It is observed from simulation results that the proposed DPSBR scheme outperforms the SPSBR-based schemes in terms of OP and SOP under the impact of different parameters on system performance.
Radio-frequency (RF) energy harvesting (EH) in wireless relaying networks has attracted considerable recent interest, especially for supplying energy to relay nodes in the Internet of Things (IoT) systems to assist the information exchange between a source and a destination. Moreover, limited hardware, computational resources, and energy availability of IoT devices have raised various security challenges. To this end, physical-layer security (PLS) has been proposed as an effective alternative to cryptographic methods for providing information security. In this study, we propose a PLS approach for simultaneous wireless information and power transfer (SWIPT)-based half-duplex (HD) amplify-and-forward (AF) relaying systems in the presence of an eavesdropper. Furthermore, we take into account both static power splitting relaying (SPSR) and dynamic power splitting relaying (DPSR) to thoroughly investigate the benefits of each one. To further enhance secure communication, we consider multiple friendly jammers to help prevent wiretapping attacks from the eavesdropper. More specifically, we provide a reliability and security analysis by deriving closed-form expressions of outage probability (OP) and intercept probability (IP), respectively, for both the SPSR and DPSR schemes. Then, simulations are also performed to validate our analysis and the effectiveness of the proposed schemes. Specifically, numerical results illustrate the nontrivial tradeoff between reliability and security of the proposed system. In addition, we conclude from the simulation results that the proposed DPSR scheme outperforms the SPSR-based scheme in terms of OP and IP under the influences of different parameters on system performance.
Simultaneous wireless information and power transfer (SWIPT) is a major breakthrough in the field of low-power wireless information transmissions. In this paper, the secrecy performance of the SWIPT-enabled relay network with full-duplex destination-aided jamming is assessed, where both the power-splitting (PS) and time-switching (TS) schemes at the relay are considered with the linear and nonlinear energy harvesting models. The relay harvests energy from the confidential signal and artificial noise sent by the source and destination, respectively, and forwards the amplified signal to the destination, in the presence of an eavesdropper. The analytical closed-form expressions of the connection outage probability (COP), secrecy outage probability (SOP), and transmission outage probability (TOP) for PS- and TS-based schemes are derived, and the closed-form expression of the lower bound of ergodic secrecy capacity (ESC) is calculated. The asymptotic-form expressions of the COP, SOP, TOP, and ESC are further analyzed to capture the valuable information in the high SNR regime. Numerical results verify the correctness of analytical results, reveal the effects of the PS/TS ratio, and transmit the signal-to-noise ratio on secrecy performance.
Physical layer security (PLS) with radio frequency (RF) energy harvesting (EH) in wireless sensor networks has received significant interest as a technology for secure information transmission and prolonging the network lifetime, as well as improving energy efficiency. This article investigates PLS for a simultaneous wireless information and power transfer (SWIPT) cooperative network, which consists of multiple sensor sources, one EH relay (R), and one destination (D) in the presence of one eavesdropper (E). Furthermore, a low-complexity, suboptimal, yet efficient sensor source selection scheme is proposed. Specifically, one sensor source is chosen to transmit information to the relay and destination such that it obtains the best channel from sensor sources to the relay. Then, by considering two relaying strategies, termed the direct link plus static power splitting-based relaying (SPSR) and direct link plus optimal dynamic power splitting-based relaying (ODPSR), the performance analysis in terms of intercept probability (IP) and outage probability (OP) is carried out for each one. Notably, the eavesdropper and destination utilize maximal ratio combining (MRC) to incorporate the received signals from the selected sensor source and the relay, which poses new challenges in obtaining the analytical expressions. In this context, we derive analytical expressions for the OP (for SPSR and ODPSR) at the destination and the IP (for SPSR) at the eavesdropper by adopting the series representation of the modified Bessel function. Finally, Monte Carlo simulations are conducted to validate the theoretical analysis and the proposed schemes’ effectiveness. Simulation results show the superiority of our scheme compared to the benchmarks.
In this paper, the physical layer security of full-duplex two-way multiple amplify-and-forward (AF) relaying network in the presence of an eavesdropper is analyzed. The closed-form expression of the approximate secrecy outage probability (SOP) based on the optimal relay selection scheme (ORS) in maximizing the secrecy capacity of proposed network is given out. Furthermore, Monte-Carlo simulation results validate the analytical expressions and show that secrecy performance can be impacted by different parameters, including the number of candidate relay and the average power of residual self-interference. The simulation results also show that the full-duplex relaying systems based on optimal relay selection scheme can significantly outperform the conventional single-relay systems and the traditional half-duplex scheme in secrecy performance.
This paper investigates physical layer security (PLS) in a half duplex (HD) relay network with radio frequency energy harvesting (EH). We consider an amplify and forward (AF) protocol in which both the source and the relay harvest energy from a dedicated power beacon, while a passive eavesdropper attempts to intercept the confidential message. Unlike prior studies that rely on asymptotic analysis or numerical integration, we derive exact closed form expressions for the outage probability (OP) and the intercept probability (IP). The proposed expressions characterize the reliability and secrecy trade-off in energy limited cooperative relaying and enable efficient performance evaluation. Monte Carlo simulations validate the analysis and match the theoretical results. Moreover, the closed form results reveal how channel conditions and harvesting duration jointly shape outage and interception behaviors. We further quantify the impacts of normalized transmit power, the time allocation factor between harvesting and information transmission, and the EH efficiency. The results provide practical guidance for selecting system parameters to meet target reliability and secrecy levels, and they show that the time allocation factor must be carefully chosen to balance harvested energy and transmission time.
The simultaneous wireless information and power transfer (SWIPT) technology is recently used to sustain the lifetime of energy-constrained relay nodes in wireless cooperative networks. An example to achieve this technology is the hybridized power-time splitting-based relaying (HPTSR) protocol. However, the information security aspect of wireless cooperative networks is important and needs adequate attention. In this paper, we perform the secrecy analysis of a SWIPT-enabled cooperative network with source–relay link-based decode-and-forward HPTSR protocol, which can enhance the operational lifetime of the relay nodes and the secrecy performance of the entire cooperative network. Specifically, we examine the secrecy performance of the considered network by deriving the analytical expressions for the near-optimal power splitting factor, secrecy outage probability, and secure energy efficiency of the system. All analytical results are confirmed by numerical simulations. Our results show that the SWIPT-enabled cooperative network outperforms the conventional relaying scheme-based network presented in literature at relatively high signal-to-noise ratios.