Dependability in Sensor, Cloud, and Big Data Systems and Applications: 5th International Conference, DependSys 2019, Guangzhou, China, November 12–15, 2019, Proceedings

In this paper, we consider a secrecy wireless-powered cognitive radio network, where an energy harvesting secondary system can share the spectrum of the primary system by assisting its transmission. In particular, we focus on the secure information transmission for the secondary system when an eavesdropper is existed to intercept the secondary user’s confidential information. Closed-form analytical expressions of primary outage probability, secondary secrecy outage probability (SOP) and the probability of non-zero secrecy capacity (PNSC) are derived. We also aim to joint design optimal time-switching ratio and power-splitting coefficient for maximizing the secondary secrecy outage probability under primary requirement constraint. To solve this nonconvex problem, we prove the biconvexity of optimization problem and then develop a corresponding algorithm to solve that optimization problem. Numerical results show that our proposed transmission scheme can provide greater secure information transmission for secondary system and guarantee the outage performance for primary system.