Recently, physical layer security (PHY-SEC) has been investigated for wireless communications to prevent eavesdropping without upper layer data encryption. This paper addresses multibeam satellite secure communication using PHY-SEC. We propose a novel system design that minimizes the satellite transmit power subject to the individual secrecy rate requested per user constraints. An iterative algorithm is proposed to update the transmission power of each beam and to achieve the optimal power allocation strategy. The convergence property of the algorithm is proved under justifiable assumptions. The performance is evaluated taking into account the impact of the channel condition with given individual secrecy rate requirement.
Recently, physical layer security (PHY-SEC) has been investigated for wireless communications to prevent eavesdropping without upper layer data encryption. This paper addresses multibeam satellite secure communication using PHY-SEC. We propose a novel system design that minimizes the satellite transmit power subject to the individual secrecy rate requested per user constraints. An iterative algorithm is proposed to update the transmission power of each beam and to achieve the optimal power allocation strategy. The convergence property of the algorithm is proved under justifiable assumptions. The performance is evaluated taking into account the impact of the channel condition with given individual secrecy rate requirement.
In this paper, we study multibeam satellite secure communication through physical (PHY) layer security techniques, i.e., joint power control and beamforming. By first assuming that the channel state information (CSI) is available and the beamforming weights are fixed, a novel secure satellite system design is investigated to minimize the transmit power with individual secrecy rate constraints. An iterative algorithm is proposed to obtain an optimized power allocation strategy. Moreover, suboptimal beamforming weights are obtained by completely eliminating the cochannel interference and nulling the eavesdroppers' signal simultaneously. In order to obtain jointly optimized power allocation and a beamforming strategy in some practical cases, e.g., with certain estimation errors of the CSI, we further evaluate the impact of the eavesdropper's CSI on the secure multibeam satellite system design. The convergence of the iterative algorithm is proven under justifiable assumptions. The performance is evaluated by taking into account the impact of the number of antenna elements, number of beams, individual secrecy rate requirement, and CSI. The proposed novel secure multibeam satellite system design can achieve optimized power allocation to ensure the minimum individual secrecy rate requirement. The results show that the joint beamforming scheme is more favorable than the fixed beamforming scheme, especially in the cases of a larger number of satellite antenna elements and higher secrecy rate requirement. Finally, we compare the results under the current satellite air-interface in DVB-S2 and the results under Gaussian inputs.
In this paper, we study multibeam satellite secure communication through physical (PHY) layer secu-rity techniques, i.e., joint power control and beamforming. By first assuming that the Channel State Infor-mation (CSI) is available and the beamforming weights are fixed, a novel secure satellite system design is investigated to minimize the transmit power with individual secrecy rate constraints. An iterative algorithm is proposed to obtain an optimized power allocation strategy. Moreover, sub-optimal beamforming weights are obtained by completely eliminating the co-channel interference and nulling the eavesdroppers ’ signal simultaneously. In order to obtain jointly optimized power allocation and beamforming strategy in some practical cases, e.g., with certain estimation errors of the CSI, we further evaluate the impact of the eavesdropper’s CSI on the secure multibeam satellite system design. The convergence of the iterative algorithm is proven under justifiable assumptions. The performance is evaluated by taking into account the impact of the number of antenna elements, number of beams, individual secrecy rate requirement, and CSI. The proposed novel secure multibeam satellite system design can achieve optimized power allocation to ensure the minimum individual secrecy rate requirement. The results show that the joint beamforming scheme is more favorable than fixed beamforming scheme, especially in the cases of a
Security threats introduced due to the vulnerability of the transmission medium may hinder the proliferation of Ka band multibeam satellite systems for civil and military data applications. This paper sets the analytical framework and then studies physical layer security techniques for fixed legitimate receivers dispersed throughout multiple beams, each possibly surrounded by multiple (passive) eavesdroppers. The design objective is to minimize via transmit beamforming the costly total transmit power on board the satellite, while satisfying individual intended users' secrecy rate constraints. Assuming state-of-the-art satellite channel models, when perfect channel state information (CSI) about the eavesdroppers is available at the satellite, a partial zero-forcing approach is proposed for obtaining a low-complexity sub-optimal solution. For the optimal solution, an iterative algorithm combining semi-definite programming relaxation and the gradient-based method is devised by studying the convexity of the problem. Furthermore, the use of artificial noise as an additional degree-of-freedom for protection against eavesdroppers is explored. When only partial CSI about the eavesdroppers is available, we study the problem of minimizing the eavesdroppers' received signal to interference-plus-noise ratios. Simulation results demonstrate substantial performance improvements over existing approaches.
Due to the broadcasting nature, satellite signals are vulnerable to potential eavesdropping attacks, which pose a significant security risk for users. Physical layer security (PLS) and cryptography technologies have been independently developed to address this security risk. However, the independent use of each technology in the power-limited satellite systems results in a trade-off problem between onboard power consumption and security performance due to additional encryption costs and dependence of PLS on the performance of eavesdroppers (Eves). In this paper, we integrate the PLS and cryptography considering the complementary properties of the adaptability to wireless channel characteristics and inherent message confidentiality for secure multibeam satellite networks. To this end, we estimate the eavesdropping risk as a function of the given number of Eves for independent and collaborative attacks. Moreover, we design an onboard power model utilized for transmission and computation, and Gaussian beamforming based on the eavesdropping risk. Then, we derive solutions for onboard power allocation, beam scheduling, and security algorithm selection in the non-orthogonal multiple access (NOMA) systems. Finally, we demonstrate that the secure transmission performance improves even under the increment of the eavesdropping risk, and the trade-off performance between cryptography and PLS is provided through analytical and simulation results.
This paper investigates the physical layer security (PLS) of a multibeam satellite communication system where the satellite transmits the private signal to a legitimate user (LU) which is intercepted by multiple eavesdroppers (Eves). By considering the imperfect channel state information (CSI) of Eve channels, we formulate the constrained problem to maximize the LU achievable secrecy rate (ASR) subject to secrecy rate outage probability constraint, the total satellite transmit power constraint and the LU rate constraint. Firstly, we adopt golden section method to transform the difficult original problem into a series easier sub-problem. Then, considering the nonconvex of sub-problem, we employ Bernstein inequality and semidefinite programming (SDP) to transform the sub-problem into solvable one. Then, we use standard software package to get the optimal beamforming (BF) weight vector through an iterative penalty-based algorithm. Finally, simulation results confirm the superiority and robustness of the designed BF scheme.
This paper investigates the physical layer security in a multibeam satellite communication system, where each legitimate user is surrounded by one eavesdropper. First of all, an optimization problem is formulated to maximize the sum of achievable secrecy rate, while satisfying the on-board satellite transmit power constraint. Then, two transmit beamforming(BF) schemes, namely, the zero-forcing (ZF) and the signal-to-leakage-and-noise ratio (SLNR) BF algorithms are proposed to obtain the BF weight vectors as well as power allocation coefficients. Finally, simulation results are provided to verify the validity of the two proposed methods and demonstrate that the SLNR BF algorithm outperforms the ZF BF algorithm.