This paper investigates the impact of opportunistic user scheduling scheme on the secure transmission for the integrated satellite terrestrial relay systems (ISTRS), where multiple legitimate terrestrial users and multiple eavesdroppers are concerned in the system. In order to obtain the best secrecy performance, the terrestrial user with the optimal signal-to-noise ratio (SNR) is selected by employing opportunistic scheduling scheme to receive the signal. In addition, this paper considers two representative eavesdropping cases, i.e., Case I which is shown as the colluding case; the eavesdroppers work together and overhear the main channel, and Case II, which is called by non-colluding case: the eavesdropper with the largest SNR will be selected to overhear the legitimate users' channel. Furthermore, we obtain the closed-form expression for the secrecy outage probability (SOP) relied on the given scheduling scheme between two representative wiretapping cases. In order to obtain further results in high SNR regime, approximate SOP expressions under both cases are also derived. At last, some meaningful Monte Carlo (MC) simulation results are given to show the correctness of the theoretical results.
This paper investigates the impact of opportunistic user scheduling scheme on the secure transmission for the integrated satellite terrestrial relay systems (ISTRS), where multiple legitimate terrestrial users and multiple eavesdroppers are concerned in the system. In order to obtain the best secrecy performance, the terrestrial user with the optimal signal-to-noise ratio (SNR) is selected by employing opportunistic scheduling scheme to receive the signal. In addition, this paper considers two representative eavesdropping cases, i.e., Case I which is shown as the colluding case; the eavesdroppers work together and overhear the main channel, and Case II, which is called by non-colluding case: the eavesdropper with the largest SNR will be selected to overhear the legitimate users' channel. Furthermore, we obtain the closed-form expression for the secrecy outage probability (SOP) relied on the given scheduling scheme between two representative wiretapping cases. In order to obtain further results in high SNR regime, approximate SOP expressions under both cases are also derived. At last, some meaningful Monte Carlo (MC) simulation results are given to show the correctness of the theoretical results.
In this paper, we investigate the impacts of joint relay selection and user scheduling scheme on the physical layer security for hybrid satellite-terrestrial relay systems, where multiple terrestrial relays, multiple terrestrial users, and multiple illegitimate eavesdroppers are considered in the network. To strengthen the system security against wiretapping attack, we present a joint opportunistic relay selection and the threshold based user scheduling scheme to balance the system performance and implementation complexity. Furthermore, two representative eavesdropping cases are considered, i.e., the Case I, colluding case: the eavesdroppers cooperate with each other and wiretap the information together, and the Case II, non-colluding case: the best eavesdropper will be chosen to wiretap the information channel. Besides, we derive the closed-form expressions for the average secrecy capacity based on the proposed relay selection and user scheduling scheme in the presence of two eavesdropping cases. To get more insights at high signal-to-noise ratios, the asymptotic expressions for the average secrecy capacity are also derived under two cases, from which we can get the effect of different parameters on the system performance conveniently. At last, analytical results are validated through comparison with the Monte Carlo simulations.
In this paper, we study the secrecy performance for an integrated satellite multiple two-way terrestrial relay network, where the non-ideal hardware, multiple vehicle eavesdroppers and multiple legitimate vehicle users are applied in the considered networks. To derive better secrecy performance, opportunistic terrestrial selection scheme is considered for the networks. Besides, the colluding eavesdropping scheme is also considered, where all the vehicle eaves work together to overhear the information. On these foundations, the closed-form expression for the secrecy outage probability is gotten. To obtain the further insights of system parameters and channel parameters in high signal-to-noise ratio regime, the asymptotic investigations for the secrecy outage probability is also investigated. At last, Monte Carlo results are given to show the efficiency and correctness of the analytical results.
This paper addresses the secure transmission problem of an integrated satellite-terrestrial relay networks (ISTRN), where multiple malicious eavesdroppers attempt to overhear the confidential signals from the satellite to a terrestrial user. Here, the relay is employed with multiple antenna and the decode-and-forward protocol is used. By supposing that the perfect instantaneous channel state information (CSI) of satellite-relay link and the statistical CSI of relay-user and relay-eavesdropper links are available at the relay, an optimization problem is first formulated to maximize the secrecy rate of the ISTRN. Then, the secure transmission scheme is designed to solve the optimization problem and obtain the closed-form beamforming weight vector. To further insight the secrecy performance of the proposed scheme, we derive the analytical expressions of the secrecy outage probability (SOP) of the considered ISTRN, where the satellite-relay link undergoes the shadowed-Rician fading, and the links of relay to user as well as eavesdroppers undergo the correlated Rayleigh fading. Finally, numerical results are given to confirm the superiority of the proposed scheme and the validity of the SOP analysis.
In this paper, we investigate the secrecy performance of multiuser dual-hop relay networks where a base station (BS) communicates with multiple legitimate users via the assistance of a trustful regenerative relay in the presence of multiple eavesdroppers. In particular, the maximal ratio transmission (MRT) scheme is exploited at the BS and a threshold-based multiuser scheduling scheme is employed over the legitimate users, while concerning the imperfect decoding at the regenerative relay. Furthermore, we consider the passive eavesdropper scenario and non-colluding eavesdropping mode. In order to quantify the secrecy performance of the considered system, the new exact closed-form expression for the secrecy outage probability is derived. In addition, conducive and simple high SNR approximation for the secrecy outage probability is also presented, which capacitates further insights into the impact of key system parameters on secrecy performance. Numerical results are provided to verify our theoretical analyses and illustrate the impact of key system parameters on the secrecy outage performance.
Satellite communication (SatCom) has attracted much attention due to its inherent characteristics. Security issues have gained severe concerns in SatCom since it is susceptible to be illegally eavesdropped by malicious ground stations within large-scale wireless coverage. In this paper, we investigate the physical layer security of a multiuser SatCom system in the presence of multiple eavesdroppers. Particularly, we propose a threshold-based scheduling scheme, where the geographically clustered eavesdroppers with both the colluded and collaborated eavesdropping scenarios are assumed. Specifically, closed-form expression for the secrecy outage probability (SOP) is derived for the passive eavesdropping scenario when the channel state information (CSI) of the eavesdroppers is unavailable. Moreover, we obtain a closed-form expression for the average secrecy capacity (ASC) of the considered system under the proposed user scheduling scheme. In order to get further insights of the proposed scheduling scheme at high signal-to-noise ratios (SNRs), the asymptotic analysis for the SOP and ASC is also demonstrated. Moreover, the reduced percentage with respect to number of user examination is also given, which validates the simplicity and efficiency of our proposed scheme compared to the traditional approaches. Numerical results deduce that with the proposed scheme, a comparable system performance with regard to the maximal selection (MS) scheme can be achieved.
This work investigates the physical layer secrecy of a multi-antenna hybrid satellite-terrestrial relay networks (HSTRN) with jamming, in which a satellite aims to make communication with a destination user by means of a relay, along with spatially random eavesdroppers.In order to weaken the signals of eavesdroppers, the conventional relay can also generate intentional interference, besides forwarding the received signal.Shadowed-Rician fading is adopted in satellite link, while Rayleigh fading is adopted in terrestrial link, eavesdropper link and jamming link.The analytical and asymptotic formulas for the system secrecy outage probability (SOP) are characterized.Practical insights on the diversity order of the network are revealed according to the asymptotic behavior of SOP at high signal-to-noise ratio (SNR) regime.Then, analysis of the system throughput is examined to assess the secrecy performance.In the end, numerical simulation results are presented to validate the theoretical analysis and point out: (1) The secrecy performance of the considered network is affected by the channel fading scenario, the system configuration; (2) Decrease of the relay coverage airspace can provide better SOP performance; (3) Jamming from the relay can improve secrecy performance without additional network resources.