400 research outputs found
A Survey of Physical Layer Security Techniques for 5G Wireless Networks and Challenges Ahead
Physical layer security which safeguards data confidentiality based on the
information-theoretic approaches has received significant research interest
recently. The key idea behind physical layer security is to utilize the
intrinsic randomness of the transmission channel to guarantee the security in
physical layer. The evolution towards 5G wireless communications poses new
challenges for physical layer security research. This paper provides a latest
survey of the physical layer security research on various promising 5G
technologies, including physical layer security coding, massive multiple-input
multiple-output, millimeter wave communications, heterogeneous networks,
non-orthogonal multiple access, full duplex technology, etc. Technical
challenges which remain unresolved at the time of writing are summarized and
the future trends of physical layer security in 5G and beyond are discussed.Comment: To appear in IEEE Journal on Selected Areas in Communication
An Overview of Physical Layer Security with Finite-Alphabet Signaling
Providing secure communications over the physical layer with the objective of
achieving perfect secrecy without requiring a secret key has been receiving
growing attention within the past decade. The vast majority of the existing
studies in the area of physical layer security focus exclusively on the
scenarios where the channel inputs are Gaussian distributed. However, in
practice, the signals employed for transmission are drawn from discrete signal
constellations such as phase shift keying and quadrature amplitude modulation.
Hence, understanding the impact of the finite-alphabet input constraints and
designing secure transmission schemes under this assumption is a mandatory step
towards a practical implementation of physical layer security. With this
motivation, this article reviews recent developments on physical layer security
with finite-alphabet inputs. We explore transmit signal design algorithms for
single-antenna as well as multi-antenna wiretap channels under different
assumptions on the channel state information at the transmitter. Moreover, we
present a review of the recent results on secure transmission with discrete
signaling for various scenarios including multi-carrier transmission systems,
broadcast channels with confidential messages, cognitive multiple access and
relay networks. Throughout the article, we stress the important behavioral
differences of discrete versus Gaussian inputs in the context of the physical
layer security. We also present an overview of practical code construction over
Gaussian and fading wiretap channels, and we discuss some open problems and
directions for future research.Comment: Submitted to IEEE Communications Surveys & Tutorials (1st Revision
Interference Leakage Neutralization in Two-Hop Wiretap Channels with Partial CSI
In this paper, we analyze the four-node relay wiretap channel, where the relay performs amplify-and-forward. There is no direct link between transmitter and receiver available. The transmitter has multiple antennas, which assist in securing the transmission over both phases. In case of full channel state information (CSI), the transmitter can apply information leakage neutralization in order to prevent the eavesdropper from obtaining any information about the signal sent. This gets more challenging, if the transmitter has only an outdated estimate of the channel from the relay to the eavesdropper. For this case, we optimize the worst case secrecy rate by choosing intelligently the beamforming vectors and the power allocation at the transmitter and the relay
Secure Transmission in Linear Multihop Relaying Networks
This paper studies the design and secrecy performance
of linear multihop networks, in the presence of randomly
distributed eavesdroppers in a large-scale two-dimensional space.
Depending on whether there is feedback from the receiver
to the transmitter, we study two transmission schemes: on-off
transmission (OFT) and non-on-off transmission (NOFT). In
the OFT scheme, transmission is suspended if the instantaneous
received signal-to-noise ratio (SNR) falls below a given threshold,
whereas there is no suspension of transmission in the NOFT
scheme. We investigate the optimal design of the linear multiple
network in terms of the optimal rate parameters of the wiretap
code as well as the optimal number of hops. These design
parameters are highly interrelated since more hops reduces the
distance of per-hop communication which completely changes the
optimal design of the wiretap coding rates. Despite the analytical
difficulty, we are able to characterize the optimal designs and
the resulting secure transmission throughput in mathematically
tractable forms in the high SNR regime. Our numerical results
demonstrate that our analytical results obtained in the high SNR
regime are accurate at practical SNR values. Hence, these results
provide useful guidelines for designing linear multihop networks
with targeted physical layer security performance.This work was supported in part by the Natural
Science Foundation of China under Grant 61401159 and Grant 61771203,
in part by the Pearl River Science and Technology Nova Program of
Guangzhou under Grant 201710010111, and in part by the Guangdong Science
and Technology Plan under Grant 2016A010101009. The work of X. Zhou
was supported by the Australian Research Council Discovery Projects under
Grant DP150103905ARC Discovery Projects Grant DP150103905
- …