Security and Reliability Performance Analysis for URLLC With Randomly Distributed Eavesdroppers.

This paper for the first time investigate the security and reliability performance of ultra-reliable low-latency communication (URLLC) systems in the presence of randomly distributed eavesdroppers, where the impact of short blocklength codes and imperfect channel estimation are jointly considered. Based on the finite-blocklength information theory, we first derive a closed-form approximation of transmission error probability to describe the degree of reliability loss. Then, we also derive an asymptotic expression of intercept probability to characterize the security performance, where the impact of secrecy protected zone is also considered. Simulation and numerical results validate the accuracy of theoretical approximations, and illustrate the tradeoff between security and reliability. That is, the intercept probability of URLLC systems can be suppressed by loosening the reliability requirement. and vice versa. More importantly, the theoretical analysis and methodologies presented in this paper can offer some insights and design guidelines for supporting secure URLLC applications in the future 6G wireless networks.