协作译码转发中继网络中的安全能效分析

Secure energy-efficiency analysis for collaborative decode-and-forward relay networks

基于物理层安全理论,研究了存在窃听用户情形下协作译码转发中继网络中的安全能效问题。安全能效,即消耗单位能量所能传输的保密信息量。在满足各节点发射功率约束和中继处最小译码速率要求下,通过功率控制实现系统的安全能效最大化。针对目标函数非凸问题,利用分式规划和DC(Difference of Convex functions)规划理论把目标函数分解为子函数通过迭代来进行优化求解。仿真结果表明,能效优化可以显著提升系统的安全能效。

Based on the theory of physical layer security, this research analyzes the secure energy-efficiency in collaborative decode-and-forward relay network with the existence of eavesdropper. Secure energy-efficiency（EE）, which is defined as the secret bits transferred with unit energy, is maximized by power allocation with constrains of maximum transistor power of all nodes and minimum decode rate of relay. To copy with the nonconvexity of objective function, this paper converts the primary problem into simple subproblem to solve through iteration by jointly applying fractional programming and difference of convex functions program- ming. The simulation results show that the power allocation can significantly improve the secure energy-efficiency of system.