Robust Beamforming and Jamming for Enhancing the Physical Layer Security of Full Duplex Radios

Abstract

In this paper, we investigate the physical layer security of a full-duplex base station (BS) aided system in the worst case, where an uplink transmitter (UT) and a downlink receiver (DR) are both equipped with a single antenna, while a powerful eavesdropper is equipped with multiple antennas. For securing the confidentiality of signals transmitted from the BS and UT, an artificial noise (AN) aided secrecy beamforming scheme is proposed, which is robust to the realistic imperfect state information of both the eavesdropping channel and the residual self-interference channel. Our objective function is that of maximizing the worst-case sum secrecy rate achieved by the BS and UT, through jointly optimizing the beamforming vector of the confidential signals and the transmit covariance matrix of the AN. However, the resultant optimization problem is nonconvex and non-linear. In order to efficiently obtain the solution, we transform the non-convex problem into a sequence of convex problems by adopting the block coordinate descent algorithm. We invoke a linear matrix inequality for finding its Karush-Kuhn-Tucker (KKT) solution. In order to evaluate the achievable performance, the worst-case secrecy rate is derived analytically. Furthermore, we construct another secrecy transmission scheme using the projection matrix theory for performance comparison. Our simulation results show that the proposed robust secrecy transmission scheme achieves substantial secrecy performance gains, which verifies the efficiency of the proposed method.

A New Frontier for IoT Security Emerging From Three Decades of Key Generation Relying on Wireless Channels

“…Wyner's seminal work has inspired significant research efforts, dedicated to ensuring that the quality of the legitimate channel remains better than that of the eavesdropping channel (see [15]- [20] and references therein). This can be achieved for example by using artificial noise [21]- [24], beamforming [25]- [28] and on-off secure transmission [29]. However, keyless secure transmission usually requires complex code design and accurate channel state information (CSI) that may not be available.…”

Physical-Layer Secret Key Generation via CQI-Mapped Spatial Modulation in Multi-Hop Wiretap Ad-Hoc Networks

“…By substituting (11) and (14) into (10), the instantaneous data rate for the transmission of confidential SM messages in the l th hop over the legitimate link, i.e. from Node l − 1 to Node l, is accomplished.…”

Robust Downlink Transmit Optimization Under Quantized Channel Feedback via the Strong Duality for QCQP

“…Therefore, robust beamforming optimization (based on the worstcase scenario) in different systems of communications has been widely studied in the past two decades (see e.g. [5], [6], [7], [8], [9], [10], [11], [12], [13], [14]). In the references, an uncertainty set of the actual channel is modeled as a ball or an ellipsoid around the channel estimate at the transmitter, and common robust optimization tools, like traditional S-lemmas [15], are employed to solve the robust beamforming design problems.…”