3 research outputs found
Multi-Antenna Relay Aided Wireless Physical Layer Security
With growing popularity of mobile Internet, providing secure wireless
services has become a critical issue. Physical layer security (PHY-security)
has been recognized as an effective means to enhance wireless security by
exploiting wireless medium characteristics, e.g., fading, noise, and
interference. A particularly interesting PHY-security technology is cooperative
relay due to the fact that it helps to provide distributed diversity and
shorten access distance. This article offers a tutorial on various
multi-antenna relaying technologies to improve security at physical layer. The
state of the art research results on multi-antenna relay aided PHY-security as
well as some secrecy performance optimization schemes are presented. In
particular, we focus on large-scale MIMO (LS-MIMO) relaying technology, which
is effective to tackle various challenging issues for implementing wireless
PHY-security, such as short-distance interception without eavesdropper channel
state information (CSI) and with imperfect legitimate CSI. Moreover, the future
directions are identified for further enhancement of secrecy performance.Comment: 17 pages, 4 figures, IEEE Communications Magazine, 201
Exploiting Interference for Secrecy Wireless Information and Power Transfer
Radio-frequency (RF) signals enabled wireless information and power transfer
(WIPT) is a cost-effective technique to achieve two-way communications and at
the same time provide energy supplies for low-power wireless devices. However,
the information transmission in WIPT is vulnerable to the eavesdropping by the
energy receivers (ERs). To achieve secrecy communications with information
nodes (INs) while satisfying the energy transfer requirement of ERs, an
efficient solution is to exploit a dual use of the energy signals also as
useful interference or artificial noise (AN) to interfere with the ERs, thus
preventing against their potential information eavesdropping. Towards this end,
this article provides an overview on the joint design of energy and information
signals to achieve energy-efficient and secure WIPT under various practical
setups, including simultaneous wireless information and power transfer (SWIPT),
wireless powered cooperative relaying and jamming, and wireless powered
communication networks (WPCN). We also present some research directions that
are worth pursuing in the future.Comment: Submitted for possible publicatio
Secure Communication Via a Wireless Energy Harvesting Untrusted Relay
The broadcast nature of the wireless medium allows unintended users to
eavesdrop the confidential information transmission. In this regard, we
investigate the problem of secure communication between a source and a
destination via a wireless energy harvesting untrusted node which acts as a
helper to relay the information; however, the source and destination nodes wish
to keep the information confidential from the relay node. To realize the
positive secrecy rate, we use destination-assisted jamming. Being an
energy-starved node, the untrusted relay harvests energy from the received
radio frequency signals, which include the source's information signal and the
destination's jamming signal. Thus, we utilize the jamming signal efficiently
by leveraging it as a useful energy source. At the relay, to enable energy
harvesting and information processing, we adopt power splitting (PS) and time
switching (TS) policies. To evaluate the secrecy performance of this proposed
scenario, we derive analytical expressions for two important metrics, viz., the
secrecy outage probability and the ergodic secrecy rate. The numerical analysis
reveals the design insights into the effects of different system parameters
like power splitting ratio, energy harvesting time, target secrecy rate,
transmit signal-to-noise ratio (SNR), relay location, and energy conversion
efficiency factor, on the secrecy performance. Specifically, the PS policy
achieves better optimal secrecy outage probability and optimal ergodic secrecy
rate than that of the TS policy at higher target secrecy rate and transmit SNR,
respectively.Comment: The paper has been submitted for possible journal publication.
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