Enhancing the physical layer security of wireless communication networks with wireless power transfer

Abstract

In recent years, the main focus for wireless networks has been shifted from spectral efficiency and quality of service (QoS) constraints to energy efficiency and green communication, especially in the fifth generation (5G) and sixth generation (6G) networks as well as IoT networks, to reduce the power consumption of low-power mobile devices and sensor. On the other hand, security has become more and more important in contemporary communication. In that situation, physical layer security has been considered as an effective method to enhance the information security beside the cryptography techniques that are used in upper layers.

Motivated by the above issue, in this dissertation I aim to propose strategies to integrate energy harvesting technology and physical layer security in the context of wireless relay networks. Specifically, I focus on studying the security and reliability performance of energy harvesting enabled relaying networks in the presence of eavesdroppers or wiretap channels. To do this, I investigate the performance of different energy harvesting strategies or protocols and various security techniques at physical layer, such as cooperative jamming, relay selection, etc. to recommend specific models that can improve the overall system performance. For performance analysis, the following performance factors are considered: outage probability (OP), intercept probability, secrecy capacity, secrecy outage probability (SOP). The closed-forms expressions of these performance factors are derived for each newly-proposed scheme.

On the other hand, the effect of different undesired condition, such as channel estimation error and hardware impairment, on the performance of the proposed energy harvesting schemes and security strategies at physical layer for wireless relay networks is also investigated. Furthermore, advanced communication techniques, including multi-hop communication, full-duplex communications, multiple-input multiple output (MIMO) communications with diversity techniques, and non-orthogonal multiple-access (NOMA), are also applied to enhance the system performance. In order to test and verify the mathematical analysis, a Monte Carlo simulation is set up and run for each analysis result.