Robust resource allocation for NOMA-assisted heterogeneous networks  

作　　者：Hao Xie Yongjun Xu 

机构地区：[1]School of Communication and Information Engineering,Chongqing University of Posts and Telecommunications,Chongqing,400065,China

出　　处：《Digital Communications and Networks》2022年第2期208-214,共7页数字通信与网络（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(No.61601071,62071078);the National Key Research and Development Program of China(No.2019YFC1511300);the Natural Science Foundation of Chongqing(No.cstc2019jcyj-xfkxX0002);the Chongqing Entrepreneurship and Innovation Program for the Returned Overseas Chinese Scholars(No.cx2020095);the Graduate Scientific Research Innovation Project of Chongqing(No.CYS20251,CYS20253).

摘　　要：As a promising technology to improve spectrum efficiency and transmission coverage,Heterogeneous Network(HetNet)has attracted the attention of many scholars in recent years.Additionally,with the introduction of the Non-Orthogonal Multiple Access(NOMA)technology,the NOMA-assisted HetNet cannot only improve the system capacity but also allow more users to utilize the same frequency band resource,which makes the NOMA-assisted HetNet a hot topic.However,traditional resource allocation schemes assume that base stations can exactly estimate direct link gains and cross-tier link gains,which is impractical for practical HetNets due to the impact of channel delays and random perturbation.To further improve energy utilization and system robustness,in this paper,we investigate a robust resource allocation problem to maximize the total Energy Efficiency(EE)of Small-Cell Users(SCUs)in NOMA-assisted HetNets under imperfect channel state information.By considering bounded channel uncertainties,the robust resource optimization problem is formulated as a mixed-integer and nonlinear programming problem under the constraints of the cross-tier interference power of macrocell users,the maximum transmit power of small base station,the Resource Block(RB)assignment,and the quality of service requirement of each SCU.The original problem is converted into an equivalent convex optimization problem by using Dinkelbach's method and the successive convex approximation method.A robust Dinkelbach-based iteration algorithm is designed by jointly optimizing the transmit power and the RB allocation.Simulation results verify that the proposed algorithm has better EE and robustness than the existing algorithms.

关 键 词：Heterogeneous network Imperfect channel state information Non-orthogonal multiple access Robust resource allocation Energy efficiency maximization 

分 类 号：TN92[电子电信—通信与信息系统]