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.
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.
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.
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 physical layer security of a satellite network, whose downlink spectral resource is shared with a terrestrial cellular network. We propose to employ a multi-antenna base station (BS) as a source of green interference to enhance secure transmission in the satellite network. By taking the mutual interference between these two networks into account, we first formulate a constrained optimization problem to maximize the instantaneous rate of the terrestrial user while satisfying the interference probability constraint of the satellite user. Then, with the assumption that imperfect channel state information (CSI) and statistical CSI of the link between the BS and satellite user are available at the BS, we present two beamforming (BF) schemes, namely, hybrid zero-forcing and partial zero-forcing to solve the optimization problem and obtain the BF weight vectors in a closed form. Moreover, we analyze the secrecy performance of primary satellite network by considering two practical scenarios, namely: Scenario I, the eavesdroppers CSI is unknown at the satellite and Scenario II, the eavesdroppers CSI is known at the satellite. Specifically, we derive the analytical expressions for the secrecy outage probability for Scenario I and the average secrecy rate for Scenario II. Finally, numerical results are provided to confirm the superiority of the proposed BF schemes and the validity of the performance analysis, as well as demonstrate the impacts of various parameters on the secrecy performance of the satellite network.
In this paper, the secrecy performance of a mixed free space optical (FSO)/radio frequency (RF) integrated satellite-high altitude platform (HAP) relaying networks for terrestrial multiusers with the existence of an eavesdropper is investigated. In this network, FSO is adopted to establish the link between the satellite and HAP for which it experiences Gamma-Gamma distributions under different detection schemes (i.e., heterodyne and intensity modulation direct detection). The transmission between the amplify-and-forward (AF) relaying HAP and terrestrial multiusers is through the RF and is modeled as shadowed-Rician fading distribution. Owning to broadcasting nature of RF link, it is assumed that an eavesdropper attempts to intercept the users’ confidential message, and the eavesdropper link is subjected to Rician distributions. Specifically, the closed-form expression for the system equivalent end-to-end cumulative distribution function is derived by exploiting the Meijer’s G and Fox’s H functions. Based on this expression, the exact closed-form expressions of the system connection outage probability, secrecy outage probability, and strictly positive secrecy capacity are obtained under the different detection schemes at HAP. Moreover, the asymptotic analyze of the system secrecy outage probability is provided to obtain more physical insights. Furthermore, the accuracy of all the derived analytical closed-form expressions is verified through the Monte-Carlo simulations. In addition, the impact of atmospheric turbulence, pointing errors, shadowing severity parameters, and Rician factor are thoroughly evaluated. Under the same system conditions, the results depict that heterodyne detection outperforms the intensity modulation direct detection.
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 constructs a radio frequency (RF)/free space optical (FSO) system for the hybrid satellite-terrestrial relay network (HSTRN), which applies the decode and forward protocol. The shadowed Rician (SR) and Gamma-Gamma (GG) distribution are used to portray the fading of RF and FSO links. The secrecy outage probability (SOP) of the HSTRN system is calculated in this paper. We deduce the closed-form expression of SOP. Moreover, we investigate the influence of atmospheric turbulence, the signal-to-noise ratio (SNR) of eavesdropping links, and shadowing conditions on the considered system.