In this paper, by taking into account the requirements of information secrecy and transmission resiliency, we present a comprehensive scheme enabling secure device-to-device (D2D) networks, where a single-antenna transmitter communicates with a half-duplex single-antenna receiver in the presence of a passive eavesdropper and an adversary jammer. Motivated by physical layer security techniques, artificial noise injection scheme is proposed to ensure communication secrecy. To improve the resiliency against jamming attack, the D2D nodes utilize the frequency hopping technique. Under this system model, we examine the achievable ergodic secrecy rate (ESR) by deriving a new closed-form expression. Furthermore, the optimal power allocation between the artificial noise and data signal is studied for maximizing the ESR. Numerical examples and discussions are provided to depict the efficiency of our proposed scheme compared with the state-of-the-arts.
In this paper, by taking into account the requirements of information secrecy and transmission resiliency, we present a comprehensive scheme enabling secure device-to-device (D2D) networks, where a single-antenna transmitter communicates with a half-duplex single-antenna receiver in the presence of a passive eavesdropper and an adversary jammer. Motivated by physical layer security techniques, artificial noise injection scheme is proposed to ensure communication secrecy. To improve the resiliency against jamming attack, the D2D nodes utilize the frequency hopping technique. Under this system model, we examine the achievable ergodic secrecy rate (ESR) by deriving a new closed-form expression. Furthermore, the optimal power allocation between the artificial noise and data signal is studied for maximizing the ESR. Numerical examples and discussions are provided to depict the efficiency of our proposed scheme compared with the state-of-the-arts.
In this article, we propose a lightweight security scheme for ensuring both information confidentiality and transmission resiliency in the Internet-of-Things (IoT) communication. A single-antenna transmitter communicates with a half-duplex single-antenna receiver in the presence of a sophisticated multiple-antenna-aided passive eavesdropper and a multiple-antenna-assisted hostile jammer (HJ). A low-complexity artificial noise (AN) injection scheme is proposed for drowning out the eavesdropper. Furthermore, for enhancing the resilience against HJ attacks, the legitimate nodes exploit their own local observations of the wireless channel as the source of randomness to agree on shared secret keys. The secret key is utilized for the frequency hopping (FH) sequence of the proposed communication system. We then proceed to derive a new closed-form expression for the achievable secret key rate (SKR) and the ergodic secrecy rate (ESR) for characterizing the secrecy benefits of our proposed scheme, in terms of both information secrecy and transmission resiliency. Moreover, the optimal power sharing between the AN and the message signal is investigated with the objective of enhancing the secrecy rate. Finally, through extensive simulations, we demonstrate that our proposed system model outperforms the state-of-the-art transmission schemes in terms of secrecy and resiliency. Several numerical examples and discussions are also provided to offer further engineering insights.
Device-to-device (D2D) communication raises new transmission secrecy protection challenges, since conventional physical layer security approaches, such as multiple antennas and cooperation techniques, are invalid due to its resource/size constraints. The full-duplex (FD) jamming receiver, which radiates jamming signals to confuse eavesdroppers when receiving the desired signal simultaneously, is a promising candidate. Unlike existing endeavors that assume the FD jamming receiver always improves the secrecy performance compared with the half-duplex (HD) receiver, we show that this assumption highly depends on the instantaneous residual self-interference cancellation level and may be invalid. We propose an adaptive jamming receiver operating in a switched FD/HD mode for a D2D link in random networks. Subject to the secrecy outage probability constraint, we optimize the transceiver parameters, such as signal/jamming powers, secrecy rates, and mode switch criteria, to maximize the secrecy throughput. Most of the optimization operations are taken off-line and only very limited on-line calculations are required to make the scheme with low complexity. Furthermore, some interesting insights are provided, such as the secrecy throughput is a quasi-concave function. Numerical results are demonstrated to verify our theoretical findings, and to show its superiority compared with the receiver operating in the FD or HD mode only.
This letter examines the physical layer security of a cellular network with inband underlay relay-aided Device-to-Device (D2D) communication, considering the scenario where the channel state information is outdated. The relay node, which operates in a full-duplex mode, can concurrently serve as a friendly jammer to enhance the cellular network secrecy performance while increasing the D2D communication data transmission. A passive eavesdropper utilizes combining approaches to combine the eavesdropping signals. Closed-form expressions for the D2D outage probability and the secrecy outage probability are derived. Furthermore, the asymptotic results are also provided.
This paper investigates the physical layer security of frequency-hopping (FH) transmission schemes when the hopping sequence is publicly known. We consider a single-antenna transmitter communicating with a legitimate receiver over a channel estimated with a known error distribution, in the presence of a passive eavesdropper whose channel statistics are available at the transmitter. We show that, when the number of hopping frequencies is sufficiently large, the instantaneous channel fluctuations induced by FH transmissions can be effectively averaged out, and the secrecy performance is accurately predicted by the ergodic secrecy rate (ESR). The ESR is maximized by selecting the optimal modulation order from a set of admissible finite constellations. We derive a closed-form condition on the optimal modulation order, which only depends on the tail probabilities of the legitimate and eavesdropper signal-to-noise ratio (SNR) distributions, and we propose an efficient algorithm for its computation. In particular, we demonstrate that a positive secrecy rate can be achieved even when the eavesdropper has a higher average SNR than the legitimate receiver, provided that the spread of the eavesdropper SNR distribution is sufficiently large. Numerical results validate the proposed framework under a variety of channel models.
An increasing number of devices exchanges data via the wireless medium into large scale, decentralized, and heterogeneous networks, leading to the concept of Internet of Things (IoT). This PhD work proposes a new practical scheme to perform physical layer security (PLS) in this IoT context.Wireless communications in IoT networks are prone to passive eavesdropping. Therefore, this work introduces a scheme that guarantees the reliability of a communication from a transmitter (Alice) towards a legitimate user (Bob), while preventing multiple passive eavesdroppers (Eve) to correctly decode the data in a worst-cases scenario, thereby considering i) Eve to be noiseless, ii) Eve equipped with an arbitrarily large number of antennas, iii) Alice imperfectly estimating Bob's channel state information (CSI). To do so, a frequency domain time-reversal (TR) precoder is proposed using orthogonal frequency-division multiplexing (OFDM) and artificial noise (AN) injection. The scheme exploits the frequency diversity selective behaviour in multipath channels, and can be incorporated into existing standards, such as in LTE or 5G networks. Different configurations are investigated, namely, single-input single-output (SISO), multiple-input single-output (MISO), and single-input multiple-output (SIMO) systems.The handshake procedures between Alice and Bob are described, both in time-division duplexing (TDD) and frequency-division duplexing (FDD) systems, highlighting the amount of CSI acquisition at Eve, which influences the secrecy performances. Depending on the handshake procedures, different decoding structures are investigated at Eve for each system configuration, considering a block-fading environment. Closed-form approximations of the signal-to-noise ratio required at Bob and the maximal CSI error that can be made at Alice, in order to guarantee a communication ergodic secrecy rate (ESR), are derived. Furthermore, the optimal amount of AN energy to inject, as well as the maximal number of eavesdropper's antennas allowed, considering imperfect CSI, are also given as closed-form expressions. A trade-off on the choice of the spreading factor of the TR precoder is established between maximizing the ESR and decreasing the percentage of outage, leading to information leaked to Eve. Finally, thanks to these results, Alice can be a-priori aware of the ESR over which she can establish a secure communication, assuming worst-case assumptions regarding the eavesdroppers. The PLS scheme presented in this PhD work therefore emerges as a promising solution to secure wireless communications in IoT networks.
This paper investigates the physical layer security of non-orthogonal multiple access (NOMA) based cooperative device-to-device (D2D) communications in cellular networks. In the networks, D2D transmitter acts as a relay of cellular networks while transmitting its own information over the spectrum of cellular networks with NOMA technique. The information transmitted by D2D transmitter is overheard by an external eavesdropper. To prevent eavesdropping, a joint design of jamming and beamforming is performed from an aspect of the power control. Particularly, the full-duplex (FD) receiver of cellular networks emits the jamming signals to deteriorate the eavesdropper's channel while receiving the confidential signals from D2D transmitter. Beamforming is designed to protect the legitimate receivers against the jamming signals. Furthermore, the secrecy outage probability of the system (SOPS) is characterized and its closed-form expression is derived. Finally, numerical results are employed to validate the accuracy of the analytical results and the superiority of the proposed scheme in terms of security performance.