基于不完美CSI的异构NOMA网络能效优化算法

Energy efficiency optimization algorithm for heterogeneous NOMA network based on imperfect CSI

为了提高异构网络的能量效率和参数摄动抑制能力,减小跨层干扰,提出了一种基于能量效率最大的异构非正交多址接入网络稳健资源分配算法。首先,考虑宏用户干扰功率约束、小蜂窝基站功率约束、资源块分配约束及小蜂窝用户服务质量约束,将资源优化问题建模为混合整数非线性分式规划问题。其次,考虑椭球有界信道不确定模型,利用凸松弛法、Dinkelbach法和连续凸近似法,将原问题转化为等价的凸优化形式,并利用拉格朗日对偶方法获得解析解。仿真结果表明,与完美CSI算法相比,所提算法具有较好的能效和稳健性。

In order to improve the suppression capability of parametric perturbation and energy efficiency(EE)of heterogeneous networks(HetNets),a robust resource allocation algorithm was proposed to maximize system EE for reducing cross-tier interference power in non-orthogonal multiple access(NOMA)based HetNets.Firstly,the resource optimization problem was formulated as a mixed integer and nonlinear programming one under the constraints of the interference power of macrocell users,maximum transmit power of small cell base station(BS),resource block assignment and the quality of service(QoS)requirement of each small cell user.Then,based on ellipsoid bounded channel uncertainty models,the original problem was converted into the equivalent convex optimization problem by using the convex relaxation method,Dinkelbach method and the successive convex approximation(SCA)method.The analytical solutions were obtained by using the Lagrangian dual approach.Simulation results verifiy that the proposed algorithm had better EE and robustness by comparing it with the existing algorithm under perfect channel state information.