Computing, Communications and IoT Applications (ComComAp)

Secure Transmit Beamforming in the RF Powered Untrusted Relay networks

Xiaochen Liu, Yuanyuan Gao, Nan Sha, Sheng Hua Huang

Published Oct 1, 2019• 0 citations

Abstract

This paper investigates secure transmission in the radio-frequency (RF) powered untrusted relay networks. The relay conducts amplify-and-forward (AF) protocol and may intercept information passively. Based on the physical-layer security technique, a two-phase communication protocol is proposed for transmit security. We aim to minimize the average total transmit power by jointly designing the transmit parameters of the networks under the security quality of service (QoS). The power minimization problem is non-convex, hence an alternative optimization (AO) based algorithm is proposed. The simulation results show that the proposed transmit scheme can significantly increase the power efficiency.

DOI: 10.1109/comcomap46287.2019.9018687

Related papers

Secrecy Rate Optimization for RF Powered Two-Hop Untrusted Relay Networks with Non-Linear EH Model

Xiaochen LIU, Yuanyuan Gao, Nan Sha +2 more

In this letter, we investigate the secure transmission in radio frequency (RF) powered two-hop untrusted relay networks, where the source node and untrusted relay are both wireless powered by an RF power supplier. Specifically, considering the non-linear energy-harvesting (EH) model, the two-process communication protocol is proposed. The secrecy rate is maximized by jointly designing the beamforming vector at source and beamforming matrix at relay, under the constraints of transmit power at RF power supplier and destination. The secrecy rate maximization (SRM) is non-convex, hence we propose an alternative optimization (AO) based iterative algorithm. Numerical results demonstrate that the proposed scheme can significantly increase the secrecy rate compared to the baseline schemes.

IEICE Transactions on Fundamentals of Electronics Communications and Computer SciencesDec 31, 20190 citations

Distributed beamforming designs to improve physical layer security in wireless relay networks

Mujun Qian, Chen Liu, Youhua Fu

Abstract This paper investigates security-oriented beamforming designs in a relay network composed of a source-destination pair, multiple relays, and a passive eavesdropper. Unlike most of the earlier works, we assume that only statistical information of the relay-eavesdropper channels is known to the relays. We propose beamforming solutions for amplify-and-forward (AF) and decode-and-forward (DF) relay networks to improve secrecy capacity. In an AF network, the beamforming design is obtained by approximating a product of two correlated Rayleigh quotients to a single Rayleigh quotient using the Taylor series expansion. Our study reveals that in an AF network, the secrecy capacity does not always grow as the eavesdropper moves away from the relays or as total relay transmit power increases. Moreover, if the destination is nearer to the relays than the eavesdropper is, a suboptimal power is derived in closed form through monotonicity analysis of secrecy capacity. While in a DF network, secrecy capacity is a single Rayleigh quotient problem which can be easily solved. We also found that if the relay-eavesdropper distances are about the same, it is unnecessary to consider the eavesdropper in a DF network. Numerical results show that for either AF or DF relaying protocol, the proposed beamforming scheme provides higher secrecy capacity than traditional approaches.

EURASIP Journal on Advances in Signal ProcessingApr 28, 20147 citations

Secure Beamforming for MIMO Two-Way Communications With an Untrusted Relay

Jianhua Mo, Meixia Tao, Yuan Liu +1 more

This paper studies the secure beamforming design in a multiple-antenna three-node system where two source nodes exchange messages with the help of an untrusted relay node. The relay acts as both an essential signal forwarder and a potential eavesdropper. Both two-phase and three-phase two-way relay strategies are considered. Our goal is to jointly optimize the source and relay beamformers for maximizing the secrecy sum rate of the two-way communications. We first derive the optimal relay beamformer structures. Then, iterative algorithms are proposed to find source and relay beamformers jointly based on alternating optimization. Furthermore, we conduct asymptotic analysis on the maximum secrecy sum-rate. Our analysis shows that when all transmit powers approach infinity, the two-phase two-way relay scheme achieves the maximum secrecy sum rate if the source beamformers are designed such that the received signals at the relay align in the same direction. This reveals an important advantage of signal alignment technique in against eavesdropping. It is also shown that if the source powers approach zero, the three-phase scheme performs the best while the two-phase scheme is even worse than direct transmission. Simulation results have verified the efficiency of the proposed secure beamforming algorithms as well as the analytical findings.

arXiv:1312.3695IEEE Transactions on Signal ProcessingFeb 20, 2014134 citations

Robust secure transmission for wireless relay networks with direct links and bounded channel uncertainties

Nanmiao Wu, Shaodan Ma

This paper investigates the problem of joint design of cooperative beamforming and artificial noise to achieve robust secure transmission in an amplify and forward (AF) relay network in the presence of multiple eavesdroppers. Specifically, the joint design is targeting to minimize the total relay transmission power while guaranteeing the quality of service at the legitimate receiver and preventing the eavesdroppers from interception. Different from prior designs, direct links between the source and the legitimate receiver/eavesdroppers are considered and no perfect channel state information is assumed. Considering bounded channel uncertainties in all links, the worst cases of the total relay transmission power, quality of service (i.e., the received signal-to-noise ratio) and security are first identified. Then an iterative algorithm is proposed to jointly design the relay beamforming and artificial noises for robust secure transmission. It is demonstrated by computer simulations that the proposed robust secure design is effective and practical when compared with the prior designs.

IEEE/CIC International Conference on Communications in China (ICCC)Jul 1, 20160 citations

Secure beamforming design of SWIPT relay network with multiple users and eavesdroppers

Lu He, Taoshen Li, Baber +4 more

Abstract This paper studies the secure beamforming design for simultaneous wireless information and power transfer (SWIPT) in a amplify-and-forward (AF) relay networks with multiple users and eavesdroppers. Each user node adopts the power splitting (PS) scheme to decode information and harvest energy simultaneously. Our objective is to minimize the total relay transmit power under the constraints of secure transmission rate and energy harvesting requirements by jointly optimizing the beamforming matrix, artificial noise covariance matrix and PS ratios. For this non-convex problem, we propose a two-stage optimization approach to convert the original problem into two sub-problems. The first subproblem uses semidefinite relaxation (SDR) technique to transform the original problem into a convex problem, and then finds the optimal solution of the second subproblem through k-dimensional exhaustive search algorithm. Furthermore, we also propose a low complexity suboptimal solution scheme based on particle swarm optimization (PSO) algorithm. Simulation results show that the proposed scheme saves transmitting power and achieves better performance than other schemes.

Journal of Physics Conference SeriesAug 1, 20202 citations

Secure Transmission in SWIPT-Powered Two-Way Untrusted Relay Networks

Jiazhen Zhang, Xiaofeng Tao, Huici Wu +1 more

In this paper, we investigate the secure transmission in two-way untrusted amplify-and-forward relay networks with simultaneous wireless information and power transfer (SWIPT). Two secure SWIPT relaying strategies, namely, secure power splitting (SPS) and secure time switching (STS), are studied with the objective of secrecy rate (SR) and secure energy efficiency (SEE) maximization. First, the high signal-to-noise ratio approximations of SR and SEE are established, based on which non-convex SPS-based and convex STS-based SR maximization problems are formulated to jointly optimize the source transmit power and resource division ratio. Suboptimal solutions are obtained by employing Dinkelbach's method and Newton's method, respectively. Furthermore, to guarantee both the energy efficiency and secure quality of service (QoS) performance, SEE maximization problems are formulated with the consideration of the energy harvesting activation constraint and the target SR requirement. The intractable non-convex SEE maximization problems are reformulated as parameter programming, transformed to Lagrange dual problems, and finally solved by two SEE resource allocation algorithms with low complexity. Numerical results verify the convergence and effectiveness of the proposed algorithms and provide new insights into relaying strategy design and secure relay placement.

IEEE AccessJan 1, 201845 citations