In this paper, we investigate the physical layer security technique of a cooperative communication network with a source node having multiple transmitting antennas, in which these antennas provide the most optimal antenna to increase security performance to a destination node via a relay node in the presence of an eavesdropper node. Here, we propose and analyze a transmission antenna selection (TAS) solution to enhance security performance in the eavesdropping channel, the cooperative communication model between the source node including multiple transmitting antennas and a destination node through a relay node and the influence of the eavesdropping node. The secrecy performance is exactly evaluated based on the secrecy outage probability (SOP) of the main channel compared to the eavesdropping channel in the Rayleigh fading channels. Monte-Carlo simulation method is applied to verify simulations and theoretical analysis results in the proposed model. The results show that when using such multiple transmit antennas significantly enhanced the system's security performance.
In this paper, we investigate the physical layer security technique of a cooperative communication network with a source node having multiple transmitting antennas, in which these antennas provide the most optimal antenna to increase security performance to a destination node via a relay node in the presence of an eavesdropper node. Here, we propose and analyze a transmission antenna selection (TAS) solution to enhance security performance in the eavesdropping channel, the cooperative communication model between the source node including multiple transmitting antennas and a destination node through a relay node and the influence of the eavesdropping node. The secrecy performance is exactly evaluated based on the secrecy outage probability (SOP) of the main channel compared to the eavesdropping channel in the Rayleigh fading channels. Monte-Carlo simulation method is applied to verify simulations and theoretical analysis results in the proposed model. The results show that when using such multiple transmit antennas significantly enhanced the system's security performance.
Physical layer security offers an efficient means to decrease the risk of confidential information leakage through wiretap links. In this paper, we address the physical-layer security in a cooperative wireless subnetwork that includes a source-destination pair and multiple relays, exchanging information in the presence of a malevolent eavesdropper. Specifically, the eavesdropper is active in the network and transmits artificial noise (AN) with a multiple-antenna transmitter to confound both the relays and the destination. We first analyse the secrecy capacity of the direct source-to-destination transmission in terms of intercept probability (IP) and secrecy outage probability (SOP). A decode-and-forward incremental relaying (IR) protocol is then introduced to improve security of communications in the presence of the active eavesdropper. Within this context, and depending on the availability of channel state information, three different schemes (one optimal and two sub-optimal) are proposed to select a trusted relay and improve the achievable secrecy rate. For each one of these schemes, and for both selection and maximum ratio combining at the destination and eavesdropper, we derive new and exact closed-form expressions for the IP and SOP. Our analysis and simulation results demonstrate the superior performance of the proposed IR-based selection schemes for secure communication. They also confirm the existence of a floor phenomenon for the SOP in the absence of AN.
We propose and analyze transmit antenna selection (TAS) to enhance physical layer security in a wiretap channel with multiple antennas at the transmitter, the receiver, and the eavesdropper. We consider the practical scenario of passive eavesdropping, where the transmitter does not have any channel state information (CSI) of the eavesdropper's channel. In the main channel between the transmitter and the receiver, we select a single antenna at the transmitter that maximizes the instantaneous signal-to-noise ratio (SNR) at the receiver. At the receiver and the eavesdropper, we consider two combining techniques: 1) maximal-ratio combining (MRC) and 2) selection combining (SC). For non-identical Rayleigh fading between the main channel and the eavesdropper's channel, we first derive new closed-form expressions for the exact and asymptotic secrecy outage probabilities. The asymptotic results accurately reveal the secrecy diversity order and the secrecy array gain. Next, we derive new closed-form expressions for the probability of positive secrecy and characterize the ε-outage secrecy capacity. We show that, under TAS/MRC and TAS/SC protocols, the secrecy outage probability approaches zero and the ε-outage secrecy capacity increases with increasing number of transmitter antennas.
In this paper, physical layer security (PLS) analysis of a cooperative wireless communication system in which the source and destination nodes communicate via a relay employing decode-and-forward protocol is performed for double Rayleigh fading channel model. For the system where the source, relay and target have single antenna, an eavesdropper with multiantenna listens the source and relay together by using maximum-ratio-combining, secrecy outage and positive secrecy capacity possibilities are obtained in closed-form. The theoretical results are verified by Monte-Carlo simulations. From the results, it is observed that as the number of antennas of the eavesdropper is increased, the PLS performance of the system worsens.
Abstract Cooperative communication has emerged as a pivotal innovation in wireless networks, allowing multiple sites with single antennas to collaborate in signal transmission, thereby improving power efficiency, enhancing spatial diversity, and increasing the reliability of signal reception. This paper introduces a cooperative communication system comprising two communicating nodes, multiple relays, and an eavesdropper. The eavesdropper attempts to intercept the signals transmitted between the two nodes. To mitigate this threat, a jamming signal is employed as artificial interference, degrading the quality of the wiretap channel and preventing the eavesdropper from successfully acquiring the transmitted data, thereby enhancing system security. The α−μ α - μ fading distribution is utilized as a generalized model for wireless channel fading. The system model is analyzed, and closed-form expressions for secrecy outage probability are derived for single-relay and the asymptotic secrecy outage probability is derived for multiple-relay scenarios, and finally the probability of the correct computation of the secrecy packets is evaluated. Analytical results are provided to substantiate the theoretical outcomes.
Wireless communication is vulnerable to eavesdropping attack due to the broadcast nature of radio propagation. In recent years, physical-layer security is emerging as a promising paradigm to prevent an eavesdropper from interception. In this paper, we consider a wireless network consisting of one source, one destination and one eavesdropper, and exploit multiple antennas at all the network nodes to improve wireless security against eavesdropping attack. Considering multiple transmit antennas at source node, we propose the optimal antenna selection (OAS) scheme to enhance the physical-layer security. We also examine the conventional single-input single-output (SISO) and space-time-coded transmission (STT) for the comparison purpose. We analyze the intercept probability performance of SISO, STT and OAS schemes in Rayleigh fading channels and theoretically prove that the proposed OAS scheme strictly outperforms conventional STT scheme in terms of the intercept probability. In addition, numerical results illustrate that with an increasing number of antennas at source and destination, the intercept probabilities of both OAS and STT schemes significantly decrease, implying the advantage of exploiting multiple antennas for wireless security against eavesdropping attack.
Physical layer security (PLS) based on cooperative communication has been regarded as a promising technique to enhance the system security. In this paper, considering the statistical information of multiple eavesdropping channels, we investigate the security performance of cooperative relay and jammer selection scheme based on maximizing secrecy capacity (SC), where an optimal relay is selected to assist the source transmission, and the selected jammer is used to transmit the interference signal to suppress the eavesdroppers. Furthermore, the asymptotic expression of secrecy outage probability (SOP), a fundamental metric in the research of physical layer security, is derived. Finally, simulation results validate the security performance of the proposed scheme, and give some significant insights into the network security.