Secure Energy Efficient Resource Allocation for OFDM Full-Duplex Relay Cooperative Networks

In this paper, we investigate the issue of resource allocation for secure communications in an orthogonal frequency division multiplexing (OFDM) based full- duplex (FD) relaying network, for maximizing the overall secure energy efficiency. Under the power constraint and minimum secrecy requirement, the resource allocation problem involves the subcarrier pairing and power allocation. The considered optimization problem is nonconvex, which is consequently transformed into a convex optimization problem by exploiting a series of mathematical tools, such as fractional programming, dual decomposition, alternative convex search, and DC programming, resulting in an efficient iterative resource allocation algorithm. Simulation results illustrate the suboptimal secure energy efficiency can be guaranteed by our proposed algorithm.