دانلود رایگان مقاله انگلیسی پارازیت به کمک هدف برای امنیت لایه فیزیکی در سیستم های رادیو شناختی - IEEE 2018

Abstract

In this paper, we investigate the security for cognitive radio networks with simultaneous wireless information and power transfer (SWIPT). In such a system, an energy-limited secondary user (SU) helps relay the traffic from a primary user (PU) to the primary receiver (PR) and assists PU secure communication using beamforming technology, in return to serve its own secondary receiver in the same spectrum. In order to further enhance the security of PU traffic performance and increase the energy harvested by SU, we propose a destination-assisted scheme in which the PR transmits jamming signal to confuse the eavesdropper, while jamming signal can also be used to power SU. The beamforming vectors and power split ratio are jointly designed to maximize the secrecy rate of PU while satisfying the rate demand of SU. It boils down to a challenging non-convex problem. We resolve this issue by a general two-stage procedure. First, by fixing the power split ratio, we obtain the optimal beamforming vectors by applying the semi-definite relaxation (SDR) technique and the Charnes Cooper transformation. Then, the problem is solved by a one-dimension search to obtain the optimal power split ratio. Extensive simulations are provided and the results demonstrate that our proposed scheme has good performance.

V. CONCLUSION

In this paper, we have considered the physical layer security for cognitive radio systems with SWIPT. We have jointly designed the beamforming vectors and power split ratio to maximize the secrecy rate of primary user while satisfying the rate demand of secondary user. A general two-stage procedure has been presented to solve this non-convex problem. Moreover, extensive simulation results are provided to evaluate our proposed scheme.