PHYSICAL LAYER SECURITY IN UNDERLAY COGNITIVE RADIO NETWORK WITH IMPERFECT RAYLEIGH CHANNEL INFORMATION

Abstract

This article investigates and evaluates the physical layer security (PLS) performance of an Underlay Cognitive Radio Network (UCRN) with imperfect Rayleigh fading channel information. First, the author examines the impact of important operational parameters such as maximum transmit power, interference power threshold, and predetermined security capacity on the system's secrecy outage probability (SOP). Next, the author studies the influence of the distance between network nodes on the SOP. Finally, the author utilizes the survey results to assess the PLS of the system. The findings indicate that increasing the maximum transmit power or the interference power threshold improves the physical layer security capability. However, imperfect channel information negatively affects the PLS performance. Moreover, increasing the predetermined security capacity reduces the PLS capability. Additionally, the survey results reveal that the distance between the secondary receiver and the primary transmitter significantly impacts the PLS performance, with a larger distance leading to lower PLS performance. Furthermore, the results demonstrate that achieving good PLS performance in UCRN is challenging due to relatively high SOP values, especially when the distance between the secondary receiver and the primary transmitter is small or when the distance between the secondary transmitter and the primary receiver is large, making it nearly impossible to achieve security.