A QUANTUM MIMO ARCHITECTURE FOR ANTENNA WIRELESS DIGITAL COMMUNICATIONS

Mohamed Nafea, Aylin Yener

This chapter considers securing wireless communications at the physical layer using multiple antennas. In particular, the multiple antenna (MIMO) wiretap channel is presented and its secrecy capacity is provided. Further investigation of the high-SNR characterization of the secrecy capacity, i.e., secure degrees of freedom, reveals that the secrecy capacity of the MIMO wiretap channel does not scale with the transmit power when the eavesdropper has an advantage over the legitimate transmitter in the number of antennas. An external multi-antenna cooperative jammer terminal is introduced to the channel model in order to improve its secrecy capacity scaling with power. The secure degrees of freedom for this new multi-terminal multi-antenna channel is characterized. While for these models the eavesdropper channel state information is known at the legitimate terminals, the chapter next removes this assumption and presents results that utilize multiple antennas in order to provide secure communications irrespective of the eavesdropper channel state. An achievable strong secrecy rate and the secure degrees of freedom characterization for the MIMO wiretap channel when the eavesdropper channel is arbitrary, varying, and unknown at the legitimate terminals are presented. Finally, the extension of this model to the two-user multiple access MIMO wiretap channel is considered and its secure degrees of freedom region is characterized. Introduction The wiretap channel and the notion of secrecy capacity, introduced in [1] and generalized by [2], have provided the framework for physical layer design for wireless channels with information theoretic guarantees against eavesdropping. A natural model in wireless communications is one which utilizes multiple antennas for transmission and reception at each node. The improvement in secrecy rate that can be obtained using multiple antennas in a point-to-point channel with an eavesdropper has been studied extensively in several references, including [3, 4]. Specifically, the secrecy capacity of the Gaussian model consisting of a multiple antenna legitimate transmitter, a multiple antenna legitimate receiver, and a multiple antenna eavesdropper, termed the multiple-input multiple-output (MIMO) wiretap channel, has been identified in full generality in [5, 6].

Mohammed Rabeea Almasaoodi, Abdulbasit M. A. Sabaawi, Sara El Gaily +1 more

Xiao Chen, Liang Pang, Yuhuan Tang +2 more

Security is an important issue in the field of wireless channel. In this paper, the security problem of Gaussian MIMO wireless hybrid channel is considered where a transmitter with multiple antennas sends information to an intended receiver with one antenna in the presence of an eavesdropper with multiple antennas. Through utilizing some of the power to produce `artificial noise', the transmitter can only degrade the eavesdropper's channel to ensure the security of the communication. But there is an inherent weakness in this scheme. Then a Hybrid Blind Space Elimination (HBSE) scheme is proposed and proved to fix the design flaw in order to strengthen the original scheme.

Jeong-Hoon Park, Jun Heo

H.S. Wang, G.H. Zeng

Security has been one of the most significant problems surrounding wireless communications, in large part due to the openness of wireless medium where eavesdropping can be easily accomplished. In this work, the prior results on secrecy capacity is extended to the Gaussian MIMO wire-tap channel, where the transmitter, the receiver and illegal wire-tapper all employ multiple antenna technique. A reasonable security criterion is firstly defined for the MIMO wire-tap channel in this paper. Next the secrecy capacity and the achievable rate-equivocation (R, d) region in this multiple antenna scenario are derived. Finally, the analyzed results are validated by the numerical simulations.

Kayako Yuda, Mitoshi Fujimoto, Ryo Yamaguchi +2 more