IRS辅助的NOMA无人机网络安全速率最大化算法

Secrecy Rate Maximization Algorithm for IRS Assisted NOMA-UAV Networks

该文研究了智能反射面(IRS)辅助基于非正交多址接入(NOMA)技术的无人机(UAV)网络中的安全传输。为了使系统安全速率最大化,该文提出联合优化无人机位置、串行干扰消除解码顺序、IRS反射矩阵和UAV发射功率的资源优化问题。由于优化问题是一个混合整数非凸优化问题,该文提出一种基于块坐标下降的迭代算法,将原问题分解为3个子问题,采用基于惩罚、半正定松弛和连续凸逼近的方法求解子问题。仿真表明,所提算法的系统安全速率优于没有IRS辅助的NOMA方案和没有IRS辅助的正交多址方案。

In this paper,secure transmission in Intelligent Reflecting Surface(IRS)assisted Unmanned Aerial Vehicle(UAV)networks based on Non-Orthogonal Multiple Access(NOMA)is investigated.A joint placement and transmit power of UAV,successive interference cancellation decoding orders,and reflecting matrix of IRS optimization problem is formulated to maximize the secrecy rate.Since the problem is mixed-integer nonconvex and challenging to solve,a block coordinate descent based iterative algorithm is developed.The original problem is decomposed into three subproblems,which are solved by exploiting the penalty-based method,the semidefinite relaxation technique,and the successive convex approximation technique.Simulation results demonstrate that the security rate of the proposed scheme is better than the scheme without IRS assisted NOMA network and the scheme without IRS assisted orthogonal multiple access network.