Wireless Physical Layer Security with Imperfect Channel State Information: A Survey

TL;DR

This survey reviews recent advances in wireless physical layer security considering imperfect channel state information, highlighting theoretical measures, transmission techniques, and challenges in practical scenarios.

Contribution

It provides a comprehensive overview of recent research on physical layer security with imperfect CSI, including theoretical measures and practical transmission strategies.

Findings

Overview of secrecy performance measures with imperfect CSI

Description of secure transmission techniques like beamforming and relay-assisted methods

Discussion of open problems and future research directions

Abstract

Physical layer security is an emerging technique to improve the wireless communication security, which is widely regarded as a complement to cryptographic technologies. To design physical layer security techniques under practical scenarios, the uncertainty and imperfections in the channel knowledge need to be taken into consideration. This paper provides a survey of recent research and development in physical layer security considering the imperfect channel state information (CSI) at communication nodes. We first present an overview of the main information-theoretic measures of the secrecy performance with imperfect CSI. Then, we describe several signal processing enhancements in secure transmission designs, such as secure on-off transmission, beamforming with artificial noise, and secure communication assisted by relay nodes or in cognitive radio systems. The recent studies of physical layer security in large-scale decentralized wireless networks are also summarized. Finally, the open problems for the on-going and future research are discussed.