22 research outputs found
Joint Power Splitting and Secure Beamforming Design in the Wireless-powered Untrusted Relay Networks
In this work, we maximize the secrecy rate of the wireless-powered untrusted
relay network by jointly designing power splitting (PS) ratio and relay
beamforming with the proposed global optimal algorithm (GOA) and local optimal
algorithm (LOA). Different from the literature, artificial noise (AN) sent by
the destination not only degrades the channel condition of the eavesdropper to
improve the secrecy rate, but also becomes a new source of energy powering the
untrusted relay based on PS. Hence, it is of high economic benefits and
efficiency to take advantage of AN compared with the literature. Simulation
results show that LOA can achieve satisfactory secrecy rate performance
compared with that of GOA, but with less computation time.Comment: Submitted to GlobeCom201
Optimization of secure wireless communications for IoT networks in the presence of eavesdroppers
The problem motivates this paper is that securing the critical data of 5G based wireless IoT network is of significant importance. Wireless 5G IoT systems consist of a large number of devices (low-cost legitimate users), which are of low complexity and under strict energy constraints. Physical layer security (PLS) schemes, along with energy harvesting, have emerged as a potential candidate that provides an effective solution to address this issue. During the data collection process of IoT, PHY security techniques can exploit the characteristics of the wireless channel to ensure secure communication. This paper focuses on optimizing the secrecy rate for simultaneous wireless information and power transfer (SWIPT) IoT system, considering that the malicious eavesdroppers can intercept the data. In particular, the main aim is to optimize the secrecy rate of the system under signal to interference noise ratio (SINR), energy harvesting (EH), and total transmits power constraints. We model our design as an optimization problem that advocates the use of additional noise to ensure secure communication and guarantees efficient wireless energy transfer. The primary problem is non-convex due to complex objective functions in terms of transmit beamforming matrix and power splitting ratios. We have considered both the perfect channel state information (CSI) and the imperfect CSI scenarios. To circumvent the non-convexity of the primary problem in perfect CSI case, we proposed a solution based on the concave-convex procedure (CCCP) iterative algorithm, which results in a maximum local solution for the secrecy rate. In the imperfect CSI scenario, we facilitate the use of S-procedure and present a solution based on the iterative successive convex approximation (SCA) approach. Simulation results present the validations of the proposed algorithms. The results provide an insightful view that the proposed iterative method based on the CCCP algorithm achieves higher secrecy rates and lower computational complexity in comparison to the other algorithms
Physical security with power beacon assisted in half-duplex relaying networks over Rayleigh fading channel: performance analysis
In this research, we proposed and investigated physical security with power beacon assisted in half-duplex relaying networks over a Rayleigh fading channel. In this model, the source (S) node communicates with the destination (D) node via the helping of the intermediate relay (R) node. The D and R nodes harvest energy from the power beacon (PB) node in the presence of a passive eavesdropper (E) node. Then we derived the integral form of the system outage probability (OP) and closed form of the intercept probability (IP). The correctness of the analytical of the OP and IP is verified by the Monte Carlo simulation. The influence of the main system parameters on the OP and IP also is investigated. The research results indicated that the analytical results are the same as the simulation ones
Wireless Information and Energy Transfer for Two-Hop Non-Regenerative MIMO-OFDM Relay Networks
This paper investigates the simultaneous wireless information and energy
transfer for the non-regenerative multipleinput multiple-output orthogonal
frequency-division multiplexing (MIMO-OFDM) relaying system. By considering two
practical receiver architectures, we present two protocols, time switchingbased
relaying (TSR) and power splitting-based relaying (PSR). To explore the system
performance limit, we formulate two optimization problems to maximize the
end-to-end achievable information rate with the full channel state information
(CSI) assumption. Since both problems are non-convex and have no known solution
method, we firstly derive some explicit results by theoretical analysis and
then design effective algorithms for them. Numerical results show that the
performances of both protocols are greatly affected by the relay position.
Specifically, PSR and TSR show very different behaviors to the variation of
relay position. The achievable information rate of PSR monotonically decreases
when the relay moves from the source towards the destination, but for TSR, the
performance is relatively worse when the relay is placed in the middle of the
source and the destination. This is the first time to observe such a
phenomenon. In addition, it is also shown that PSR always outperforms TSR in
such a MIMO-OFDM relaying system. Moreover, the effect of the number of
antennas and the number of subcarriers are also discussed.Comment: 16 pages, 12 figures, to appear in IEEE Selected Areas in
Communication