In this paper, we consider a low earth orbit satellite communication system with a legitimate user and an eavesdropper and investigate its secrecy performance. Considering the beam coverage of the satellites, we propose a system where a friendly jammer satellite transmits artificial noise signals only to eavesdroppers. We obtain the cumulative distribution functions (CDFs) of the signal-to-interference-plus-noise ratios taking into account the Nakagami-𝑚 fading and the positions of ground users and satellites. The CDFs are used to derive the analytical forms of the probability of non-zero secrecy capacity, secrecy capacity outage probability, and average secrecy capacity. In addition, for tractability and insight, asymptotic forms are also investigated at a high-power regime. Finally, we present the numerical results to validate the obtained expressions and show the diversity order of the secrecy capacity.
In this paper, we consider a low earth orbit satellite communication system with a legitimate user and an eavesdropper and investigate its secrecy performance. Considering the beam coverage of the satellites, we propose a system where a friendly jammer satellite transmits artificial noise signals only to eavesdroppers. We obtain the cumulative distribution functions (CDFs) of the signal-to-interference-plus-noise ratios taking into account the Nakagami-𝑚 fading and the positions of ground users and satellites. The CDFs are used to derive the analytical forms of the probability of non-zero secrecy capacity, secrecy capacity outage probability, and average secrecy capacity. In addition, for tractability and insight, asymptotic forms are also investigated at a high-power regime. Finally, we present the numerical results to validate the obtained expressions and show the diversity order of the secrecy capacity.
This paper investigates the physical layer security (PLS) for the transmission of confidential information over satellite communication systems under unified framework. The generalized shadowed-Rician (SR) fading is utilized to model the satellite channel, and multiple legitimate users are served to cooperatively receive the broadcast signal with a cluster of unauthorized eavesdroppers. In particular, the channel estimation error (CEE) is considered for both the legitimate user and eavesdropping links. Based on the practical channel modeling, we derive the closed-form expressions for the probability of strictly positive secrecy capacity (PSPSC), secrecy outage probability (SOP), and average secrecy capacity (ASC) of the considered satellite communication system in the presence of imperfect channel estimation (ICE), which can provide efficient methods to evaluate the impacts of various propagation parameters on the secrecy performance. In order to obtain further insights into the key parameters on the secrecy performance at high signal-to-noise ratios (SNRs), the asymptotic expressions of the SOP and ASC are also derived. Monte Carlo simulation results are provided to verify the correctness of our performance analysis.
Low Earth Orbit (LEO) satellite communications are vulnerable to eavesdropping due to open wireless links. To address this issue, a simplified artificial noise (AN)-aided physical layer security scheme is proposed. A practical system model including a multi-antenna LEO satellite, a single-antenna ground user, and multiple eavesdroppers is established, considering shadowed Rician fading and imperfect channel state information (CSI). The AN is projected into the null space of the legitimate user’s channel to avoid interference, while suppressing eavesdroppers. A fixed power allocation strategy is adopted for easy implementation. Simulation results show that the proposed scheme outperforms traditional methods in secrecy rate and secrecy outage probability (SOP) with low computational complexity, making it suitable for resource-constrained LEO satellite systems.
In this paper, we investigate the physical layer security of land mobile satellite (LMS) communication networks, where the multiple legitimate users and eavesdroppers are considered in the system. In order to obtain the best system performance, we propose the cooperating scheme for legitimate users to receive the main signal. Besides, we design two representative eavesdropping scenes for the eavesdroppers, namely, Scene I, colluding scene: the eavesdroppers cooperate with each other and wiretap the information of the main channel together, and the Scene II, non-colluding scene which is the best eavesdropping scene, namely, the most harmful eavesdropper will be selected to overhear the information channel. Furthermore, we obtain the closed-form expressions for the non-zero probability of secrecy capacity, the secrecy outage probability (SOP), and average secrecy capacity (ASC) based on the proposed user cooperation scheme in the presence of two eavesdropping scenes. In order to obtain more insights at the high signal-to-noise-ratios, the asymptotic expressions for the SOP and ASC are also derived under two scenes, from which we can derive the effect of different parameters on the system performance conveniently. Finally, some representative Monte Carlo simulation results are provided to verify the correctness of the obtained analytical results.
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 study examines physical layer security in a cognitive satellite-terrestrial network where a ground user (GU) transmits confidential data to a Geostationary Earth Orbit (GEO) satellite via an untrusted Low Earth Orbit (LEO) relay adopting the Amplify-and-Forward (AF) relay strategy. To counter eavesdropping risks from the relaying LEO satellite, a friendly LEO jammer emits artificial noise. The secrecy rate is analyzed under cognitive radio constraints, considering interference thresholds, relay gain, and GU-LEO link shadowing. Numerical results show that increasing the interference threshold initially improves the secrecy rate but saturates when the maximum transmit power constraint at the GU is reached. When this maximum power constraint is removed, the interference threshold can be adjusted to optimize the secrecy rate. Additionally, we observe that lighter shadowing conditions generally enhance the secrecy rate, even though they improve the untrusted relay's channel. These findings offer valuable insights into optimizing security in cognitive satellite-terrestrial networks.
Low Earth Orbit (LEO) satellite communications are vulnerable to eavesdropping over open wireless links. This paper proposes a simplified artificial noise (AN)-aided physical layer security scheme. A system model with a multi-antenna LEO satellite, a single-antenna ground user, and multiple eavesdroppers is built under shadowed-Rician fading and imperfect channel state information. AN is projected into the null space of the legitimate channel to avoid interference, and fixed power allocation is adopted for low complexity. Simulations show the scheme achieves better secrecy rate and secrecy outage probability than traditional methods, suitable for resource-constrained LEO satellite systems.