Title :
Robust Secure Transmission in MISO Channels Based on Worst-Case Optimization
Author :
Huang, Jing ; Swindlehurst, A. Lee
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Univ. of California, Irvine, CA, USA
fDate :
4/1/2012 12:00:00 AM
Abstract :
This paper studies robust transmission schemes for multiple-input single-output (MISO) wiretap channels. Both the cases of direct transmission and cooperative jamming with a helper are investigated with imperfect channel state information (CSI) for the eavesdropper links. Robust transmit covariance matrices are obtained based on worst-case secrecy rate maximization, under both individual and global power constraints. For the case of an individual power constraint, we show that the nonconvex maximin optimization problem can be transformed into a quasi-convex problem that can be efficiently solved with existing methods. For a global power constraint, the joint optimization of the transmit covariance matrices and power allocation between the source and the helper is studied. We also investigate the robust wiretap transmission problem for the case with a quality-of-service constraint at the legitimate receiver. Numerical results show the advantage of the proposed robust design. In particular, for the global power constraint scenario, although cooperative jamming is not necessary for optimal transmission with perfect eavesdropper´s CSI, we show that robust jamming support can increase the worst-case secrecy rate and lower the signal to interference-plus-noise ratio at the eavesdropper in the presence of channel mismatches between the transmitters and the eavesdropper.
Keywords :
concave programming; cooperative communication; covariance matrices; minimax techniques; quality of service; radio receivers; MISO wiretap channel; cooperative jamming; direct transmission; eavesdropper link; global power constraint scenario; imperfect channel state information; individual power constraint; joint optimization; legitimate receiver; multiple-input single-output wiretap channel; nonconvex maximin optimization problem; optimal transmission; power allocation; quality-of-service constraint; quasiconvex problem; robust design; robust secure transmission; robust wiretap transmission problem; signal to interference-plus-noise ratio; transmit covariance matrix; transmitter; worst-case optimization; worst-case secrecy rate maximization; Covariance matrix; Interference; Jamming; Optimization; Quality of service; Resource management; Robustness; Convex optimization; cooperative jamming; physical layer security; robust beamforming;
Journal_Title :
Signal Processing, IEEE Transactions on
DOI :
10.1109/TSP.2011.2182344