Secrecy Cognitive Gain of Cognitive Radio Sensor Networks with Primary Outage Constraint

摘要

This paper studies the physical layer security issue for cognitive radio sensor networks (CRSNs) with primaryoutage constraint, for which a tractable framework is developed to analyze the secrecy performancefor CRSNs related to the random channel characteristics, the spatial distributions of nodes, the nearestneighbour routing protocol, and the aggregate interference. Based on stochastic geometry technique, anovel random analysis method is proposed to derive the closed-form expression of secrecy transmissioncapacity and analyze the connection outage probability (COP) and secrecy outage probability (SOP) forboth secondary (SR) and primary (PR) systems. Then, the concept of secrecy cognitive gain is producedto highlight the effect of SR systems with secrecy on the whole networks security. Comparing with asingle PR system, the SR system is beneficial to enhance the secrecy level for overlaid CRSNs. In addition,the maximum achievable secrecy capacity is achieved through optimizing the density of SR systemssatisfying outage constraints of PR and SR systems. Analytical results provide insights into regimes inwhich the SR system with secrecy is beneficial for the overlaid network secrecy.