Robust transmit design for secure AF relay networks with imperfect CSI

Abstract

This paper studies robust transmit design for secure AF relay networks with imperfect channel state information (CSI). Two CSI error models, deterministically bounded error model and stochastic error model, are considered. In order to use the power at relays more efficiently, a joint cooperative relaying and jamming scheme is considered, where relays cooperate to forward the source signal and simultaneously they cooperate to send jamming signals to confuse the eavesdroppers. In this joint cooperative relaying and jamming framework, we address the robust joint optimization of the relay weights and the input covariance matrix of jamming signals for secrecy rate maximization (SRM), under both total and individual relay power constraints. Specifically, for the case of deterministically bounded error model, where the CSI error can be specified by an uncertainty set, we maximize the worst-case secrecy rate. While for the case of stochastic error model, where the probability distribution of the CSI error is Gaussian, we maximize the outage constrained secrecy rate. The challenge of these considered SRM-based optimizations lies in their non-convexity. This paper shows that such SRM-based optimization can be solved in a convex fashion and via solving a sequence of semidefinite programs (SDPs). Numerical results are presented to show the efficacy of the proposed scheme.

Generalized Beamforming Design for Cooperative MIMO Multirelay Networks with Infinite Constraints and Imperfect CSI

“…In order to circumvent these problems, by taking into account the channel uncertainties, the imperfect CSI scenario has been studied in [7,[14][15][16][17][18][19][20]. The authors in [14] considered robust transceiver design in a multiuser MIMO multirelay cognitive radio network with interference power constraints and individual transmission power constraints.…”

“…By taking the imperfect channel state information into consideration, in [17], the robust AF-MIMO transceiver optimization is developed in order to combat correlated channel uncertainties, where the matrix-form conjugate gradient (MCG) method is used for optimization. Moreover, the robust joint optimization of the relay weights and the input covariance matrix of jamming signals for secrecy rate maximization is addressed in [18]. In [19], the authors investigated the worst-case robust relay precoder optimization for multiantenna AF relaying in the presence of either deterministic additive or multiplicative channel uncertainties.…”

Individual secrecy of fading homogeneous multiple access wiretap channel with successive interference cancellation

“…A great deal of research work addressed how to improve secrecy performance, some from the perspective of precoding and beamforming [7][8][9][10], some via the utilization of artificial noise or jamming [11][12][13][14], and some jointly applying these approaches [15][16][17][18]. Overall, the purpose of exploiting these techniques is to enlarge the capacity difference between main and eavesdropper channels.…”