90 research outputs found
TAS-Based Incremental Hybrid Decode–Amplify–Forward Relaying for Physical Layer Security Enhancement
In this paper, a transmit antenna selection (TAS)-
based incremental hybrid decode-amplify-forward (IHDAF)
scheme is proposed to enhance physical layer security in cooperative
relay networks. Specifically, TAS is adopted at the
source in order to reduce the feedback overhead. In the proposed
TAS-based IHDAF scheme, the network transmits signals to the
destination adaptive select direction transmission mode, AF mode
or DF mode depending on the capacity of the source-relay link
and source-relay link. In order to fully examine the benefits
of the proposed TAS-based IHDAF scheme, we first derive its
secrecy outage probability (SOP) in a closed-form expression. We
then conduct asymptotic analysis on the SOP, which reveals the
secrecy performance floor of the proposed TAS-based IHDAF
scheme when no channel state information is available at the
source. Theoretical analysis and simulation results demonstrate
that the proposed TAS-based IHDAF scheme outperforms the
selective decode-and-forward (SDF), the incremental decodeand-forward
(IDF), and the noncooperative direction transmission
(DT) schemes in terms of the SOP and effective secrecy
throughout, especially when the relay is close to the destination.
Furthermore, the proposed TAS-based IHDAF scheme offer a
good trade-off between complexity and performance compare
with using all antennas at the source.ARC Discovery Projects Grant DP150103905
A New Secure Transmission Scheme With Outdated Antenna Selection
We propose a new secure transmission scheme in
the multi-input multi-output multi-eavesdropper wiretap channel.
In this channel, the NA-antenna transmitter adopts transmit
antenna selection (TAS) to choose the antenna that maximizes
the instantaneous signal-to-noise ratio (SNR) at the receiver to
transmit, while the NB-antenna receiver and the NE-antenna
eavesdropper adopt maximal-ratio combining (MRC) to combine
the received signals. We focus on the practical scenario where
the channel state information (CSI) during the TAS process is
outdated. In this scenario, we propose a new transmission scheme
to prevent the detrimental effect of the outdated CSI on the
wiretap codes design at the transmitter. To thoroughly assess
the secrecy performance achieved by the proposed scheme, we
derive new closed-form expressions for the exact secrecy outage
probability and the probability of non-zero secrecy capacity for
arbitrary SNRs. We also derive new compact expressions for the
asymptotic secrecy outage probability at high SNRs. Notably,
in the analysis we take spatial correlation at the receiver into
consideration. Apart from the advantage of our scheme over
the conventional TAS/MRC scheme, we demonstrate that the
outdated TAS reduces the secrecy diversity order from NANB
to NB. We also demonstrate that antenna correlation improves
the secrecy performance at low SNR but deteriorates the secrecy
performance at medium and high SNRs, by affecting the secrecy
array gain only.ARC Discovery Projects Grant DP150103905
Secure Multiuser Communications in Wireless Sensor Networks with TAS and Cooperative Jamming
In this paper, we investigate the secure transmission in wireless sensor networks (WSNs) consisting of one multiple-antenna base station (BS), multiple single-antenna legitimate users, one single-antenna eavesdropper and one multiple-antenna cooperative jammer. In an effort to reduce the scheduling complexity and extend the battery lifetime of the sensor nodes, the switch-and-stay combining (SSC) scheduling scheme is exploited over the sensor nodes. Meanwhile, transmit antenna selection (TAS) is employed at the BS and cooperative jamming (CJ) is adopted at the jammer node, aiming at achieving a satisfactory secrecy performance. Moreover, depending on whether the jammer node has the global channel state information (CSI) of both the legitimate channel and the eavesdropper's channel, it explores a zero-forcing beamforming (ZFB) scheme or a null-space artificial noise (NAN) scheme to confound the eavesdropper while avoiding the interference to the legitimate user. Building on this, we propose two novel hybrid secure transmission schemes, termed TAS-SSC-ZFB and TAS-SSC-NAN, for WSNs. We then derive the exact closed-form expressions for the secrecy outage probability and the effective secrecy throughput of both schemes to characterize the secrecy performance. Using these closed-form expressions, we further determine the optimal switching threshold and obtain the optimal power allocation factor between the BS and jammer node for both schemes to minimize the secrecy outage probability, while the optimal secrecy rate is decided to maximize the effective secrecy throughput for both schemes. Numerical results are provided to verify the theoretical analysis and illustrate the impact of key system parameters on the secrecy performance.This work was supported by the National Science Foundation of China (No. 61501507), and the Jiangsu Provincial Natural Science Foundation of China (No. BK20150719). The work of Nan Yang is supported by the Australian Research Council Discovery Project (DP150103905)
Optimal Number of Transmit Antennas for Secrecy Enhancement in Massive MIMOME Channels
This paper studies the impact of transmit antenna selection on the secrecy
performance of massive MIMO wiretap channels. We consider a scenario in which a
multi-antenna transmitter selects a subset of transmit antennas with the
strongest channel gains. Confidential messages are then transmitted to a
multi-antenna legitimate receiver while the channel is being overheard by a
multi-antenna eavesdropper. For this setup, we approximate the distribution of
the instantaneous secrecy rate in the large-system limit. The approximation
enables us to investigate the optimal number of selected antennas which
maximizes the asymptotic secrecy throughput of the system. We show that
increasing the number of selected antennas enhances the secrecy performance of
the system up to some optimal value, and that further growth in the number of
selected antennas has a destructive effect. Using the large-system
approximation, we obtain the optimal number of selected antennas analytically
for various scenarios. Our numerical investigations show an accurate match
between simulations and the analytic results even for not so large dimensions.Comment: 6 pages, 4 figures, IEEE GLOBECOM 201
On Secrecy Performance for Energy-Harvesting Multi-Antenna Relaying Networks with a Dual-Use Source
This paper studies the secrecy performance of an energy-harvesting relaying system in the presence of a dual-use source node and an eavesdropper. Specifically, the source has dual roles in the dual-hop communication: 1) to transmit confidential information in the first hop; 2) to generate jamming signal to interfere the eavesdropper in the second hop. Moreover, the multi-antenna relay deploys a power-splitting harvesting scheme to coordinate the information receiving and energy harvesting, and adopts maximal ratio combining technique to process the multiple copies of signals. Considering decode-and-forward protocol and transmit antenna selection scheme, we derive an analytical expression for secrecy outage probability, and perform Monte Carlo simulation to validate the analysis. Analytical results show that the SOP performance with the dual-use source node can be effectively improved when the relay-destination channel does not have absolute advantage over the relay-eavesdropper channel
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