Destination-based Jamming Research Articles

Optimal Secure Channel Access in Distributed Cooperative Networks With Untrusted Relay

This paper investigates optimal channel access strategies to improve secure communications over a distributed cooperative wireless network with multiple user pairs and an untrusted amplify-and-forward (AF) relay. The user pairs communicate directly or via the relay. To enable secure communication, we formulate a channel access problem to maximize the average secrecy system throughput with destination-based jamming. Using optimal sequential planned decision theory, we propose an optimal channel access strategy where the winning user pair uses direct transmission, cooperative AF relaying, or cooperative jamming in an adaptive manner. We rigorously prove the optimality of the solution and provide a distributed channel access algorithm based on the pure threshold structure, which is easy to implement. Numerical results demonstrate effectiveness and efficiency of the proposed strategy compared to alternatives.

Impact of Wireless Energy Transfer Strategies on the Secrecy Performance of Untrustworthy Relay Networks

This work investigates the secrecy outage performance of a dual-hop relaying network with an untrustworthy energy-constrained amplify-and-forward relay. A destination-based jamming technique is adopted in order to prevent the relay from decoding confidential messages from the source. Additionally, three time switching-based wireless energy transfer strategies are investigated for supplying power to the relay. For these three strategies, we derive simple closed-form asymptotic expressions for the secrecy outage probability at high signal-to-noise ratio. Moreover, we provide analytical expressions for the optimum power allocation factor for the information transmission phase. Finally, Monte Carlo simulations are carried out to verify the theoretical results through different illustrative cases.

Secure Multiuser Scheduling for Hybrid Relay-Assisted Wireless Powered Cooperative Communication Networks With Full-Duplex Destination-Based Jamming

In this paper, we investigate secure communication in a hybrid relay (HR)-assisted wireless powered cooperative communication network (WPCCN), where an eavesdropper tries to intercept the data transmitted by a source user and the HR simultaneously. The HR has the ability to wireless powered the energy-constrained multiple users in the downlink and to relay the received confidential information in the uplink. In particular, the full-duplex destination-based jamming (FD-DBJ) strategy is exploited to improve the secrecy performance. Moreover, in order to conduct effective secure communications, we design two multiuser scheduling schemes, i.e., random user selection (RUS), and best user selection (BUS) based on the main channel quality. In order to evaluate the secrecy performance, we analytically derive the energy outage probability (EOP), the secrecy outage probability (SOP), and the hybrid outage probability (HOP), respectively. As such, we formulate the secrecy throughput (ST) maximization problem to optimize the predetermined transmission rate. Our analysis and numerical results reveal that: 1) The BUS scheme has better security performance. 2) Both of the energy conversion efficiency and the number of users have a positive effect on secrecy performance. 3) The FD-DBJ scheme is an effective method to achieve secure communications. 4) The time-switching factor and predetermined transmission rate have a crucial influence on the secrecy performance, which should be considered carefully in system design.

On the Secrecy Performance and Power Allocation in Relaying Networks With Untrusted Relay in the Partial Secrecy Regime

Recently, three useful secrecy metrics based on the partial secrecy regime were proposed to analyze secure transmissions on wireless systems over quasi-static fading channels, namely: generalized secrecy outage probability, average fractional equivocation, and average information leakage. These metrics were devised from the concept of fractional equivocation, which is related to the decoding error probability at the eavesdropper, so as to provide a comprehensive insight on the practical implementation of wireless systems with different levels of secrecy requirements. Considering the partial secrecy regime, in this paper we examine the secrecy performance of an amplify-and-forward relaying network with an untrusted relay node, where a destination-based jamming is employed to enable secure transmissions. In this regard, a closed-form approximation is derived for the generalized secrecy outage probability, and integral-form expressions are obtained for the average fractional equivocation and the average information leakage rate. Additionally, equal and optimal power allocation schemes are investigated and compared for the three metrics. From this analysis, we show that different power allocation approaches lead to different system design criteria. The obtained expressions are validated via Monte Carlo simulations.

Secrecy Transmission for Self-Energy Recycling Untrusted Relay Networks With Imperfect Channel State Information

For the self-energy recycling (SER) untrusted relay network, a two-phase destination-based jamming (DBJ) protocol is proposed, in which the destination transmits the jamming signal to reduce the received SNR of the untrusted relay node in the first phase and the relay node operated in full-duplex (FD) mode for simultaneous energy transfer and information relaying in the second phase. In addition, the loopback interference (LI) generated by FD relay node can be reused as part of energy. To satisfy some practical application scenarios, we consider the imperfect channel estimation error at the destination. Considering the total power constraint and the quality of service (QoS) requirement at the destination, the secrecy rate maximization problem is formulated by optimizing the transmission power of source and destination. However, the formulated problem is non-convex and difficult to solve directly. To cope with this difficulty, an iterative power allocation algorithm is proposed. The key idea of the proposed algorithm first integrates the non-convex constraint into the objective function by the exact penalty method. Then the difference of convex functions (DC) programming can be utilized to convert the non-convex objective function into the approximate convex function and the sub-optimal transmission power of source and destination can be obtained by the traditional convex programming. Simulation results show the superiority security performance of the proposed scheme with the traditional schemes.

Hybrid Destination-Based Jamming and Opportunistic Scheduling with Optimal Power Allocation to Secure Multiuser Untrusted Relay Networks

In this paper, we investigate secure communication for a dual-hop multiuser relay network, where a source communication with N ( N ≥ 1 ) destinations via an untrusted variable gains relay. To exploit multiuser diversity while protecting source’s confidential message, we first propose a joint destination-based jamming and opportunistic scheduling (DJOS) scheme. Then, we derive closed-form approximated and asymptotic expressions of the secrecy outage probability (SOP) for the considered system with DJOS. Furthermore, we determine an asymptotical optimal power allocation (OPA), which minimizes the asymptotic SOP, to further improve the secrecy performance. Our analytical results show that the achievable secrecy diversity order in terms of SOP with fixed power allocation is min ( 1 , N 2 ) , whereas, with OPA, the achievable secrecy diversity order can be improved up to min ( 1 , 2 N N + 2 ) . This interesting result reveals that OPA can improve the secrecy diversity order of the single-user network. This is intuitive since full diversity order of 1 cannot be achieved when N = 1 , thus leaving some space for OPA to improve the diversity order. Nevertheless, for N ≥ 2 , the effect of OPA is to increase the secrecy array gain rather than the secrecy diversity order since full diversity order 1 has been achieved by the OS scheme. Finally, simulation results are presented to validate our analysis.

Antenna Mode Switching for Full-Duplex Destination-Based Jamming Secure Transmission

We investigate the secrecy rate optimization problem in a wiretap channel with a single-antenna source, a single-antenna eavesdropper, and a multiple-antenna full-duplex (FD) destination. To fully utilize the spatial degrees-of-freedom of multiple antennas, the function of antennas at the destination is not predefined, i.e., each antenna can operate in a transmit or receive mode. We propose a low-complexity near-optimal joint optimization scheme by jointly applying the dynamic antenna mode switching (AMS) and optimal power allocation (OPA) techniques, to maximize the secrecy rate of the FD destination-based jamming (DBJ) system. The proposed joint optimization scheme is valid for two different eavesdropping channel state information (ECSI) availability cases, i.e., instantaneous ECSIs and statistical ECSIs. Specifically, closed-form expressions of OPA factors are first derived, and then the optimal transmit and receive antennas sets at the destination are determined by combining the OPA factor and applying a greedy-search-based AMS approach for both ECSIs availabilities, respectively. Moreover, through complexity analysis, the search complexity of the proposed scheme is proven to be significantly reduced compared with the exhaustive searching method. Simulation results verify the secrecy performance superiority of the proposed scheme over the conventional FD-DBJ method.

Performance analysis of secure AF relay networks using cooperative jamming under outdated CSI

This paper studies cooperative transmission for securing a two-hop network where the eavesdropper can wiretap the relay channels. With outdated channel state information (CSI), we propose an opportunistic relaying with destination-based jamming scheme, where one relay is chosen to forward the confidential signal and the destination sends jamming signal to confuse the eavesdropper. To reveal the capability of the proposed scheme in improving the system secrecy, we investigate the two common performance metrics under different assumptions on the eavesdropper CSI. First, lower bound on the ergodic secrecy capacity (ESC) is derived assuming perfect knowledge of the eavesdropper channel gains. We, then, extend our results to the scenario where only the legitimate channel gain is known. Here, lower bound on the secrecy outage probability (SOP) is obtained. To further improve the utility of the destination, under total power constraint, a power allocation between data signal and jamming noise is considered. Both the analysis and simulation results indicate that the system performance is significantly improved in terms of both ESC and SOP when the jamming power at the destination is adjusted according to the selected relay position. We verify that, with outdated CSI, the secrecy performance of opportunistic relaying is severely degraded.

Optimised power allocation to maximise secure rate in energy harvesting relay network

For an energy harvesting relay network, an optimal secure transmission scheme is proposed. In the case of limited harvesting energy and total power, destination-based jamming technique is applied to protect the confidential information from relay's jamming and eavesdropping. Moreover, the penalty function algorithm is utilised to obtain the optimal power allocation factor to maximise secure rate. The impacts of power allocation factor and energy transformation efficiency on the system secure rate are analysed. Simulation results validate the correctness and efficiency of the proposed scheme.

Ergodic Achievable Secrecy Rate of Multiple-Antenna Relay Systems With Cooperative Jamming

This paper investigates the ergodic achievable secrecy rate (EASR) of multiple-antenna amplify-and-forward relay systems, where one eavesdropper can wiretap the relay. To reveal the capability of the multiple-antenna relay in improving the secrecy performance, we derive new tight closed-form expressions of the EASR for three secure transmission schemes: artificial noise aided precoding (ANP), destination based jamming (DBJ) and eigen-beamforming (EB). We also derive the lower bounds of the EASR for ANP and DBJ with a large antenna array at the relay, and investigate their corresponding asymptotic performance in the high SNR and low SNR regimes to show valuable intrinsic insights as well. Based on the asymptotic analysis, we optimally allocate the power to the information signal and the artificial noise. Both the analysis and simulation results indicate that, in the moderate-to-high SNR regime, ANP achieves considerable performance gain over DBJ and EB, while in the low SNR regime, EB outperforms the other two schemes with equal power allocation. As SNR grows large, the EASR of EB approaches a constant independent of the first hop channel. Moreover, in the high SNR regime, it is optimal to allocate around half of total power to artificial noise for ANP and most of the power to artificial noise for DBJ.

Joint Power Allocation at the Base Station and the Relay for Untrusted Relay Cooperation OFDMA Network

The secure communication that multiple OFDMA-based cell-edge mobile stations (MS) can only transmit confidential messages to base station (BS) through an untrusted intermediate relay (UR) is discussed. Specifically, with the destination-based jamming (DBJ) scheme and fixed MS transmission power assumption, our focus is on the joint BS and US power allocation to maximize system sum secrecy rate. We first analyze the challenges in solving this problem. The result indicates that our nonconvex joint power allocation is equivalent to a joint MS access control and power allocation. Then, by problem relaxation and the alternating optimization approach, two suboptimal joint MS access control and power allocation algorithms are proposed. These algorithms alternatively solve the subproblem of joint BS and UR power allocation and the subproblem of MS selection until system sum secrecy rate is nonincreasing. In addition, the convergence and computational complexity of the proposed algorithms are analyzed. Finally, simulations results are presented to demonstrate the performance of our proposed algorithms.

Performance Study of Two-Hop Amplify-and-Forward Systems With Untrustworthy Relay Nodes

This paper investigates the problem of secure communication for amplify-and-forward (AF) systems with untrustworthy relay nodes. To achieve positive secrecy rate, the destination-based jamming (DBJ) technique is applied. We first focus on the single-relay scenario, for which the closed-form expression for the lower bound of the ergodic secrecy capacity (ESC) is derived. Afterward, we extend the DBJ method to the multi-relay scenario and propose a secure relay selection scheme that can maximize the achievable secrecy rate. Based on the extreme-value theory, the approximate ESC is characterized. Our work reveals an interesting result that, when the relay nodes are untrustworthy, the system performance worsens as the number of relays increases.