Ambient Backscatter Communications over NOMA Downlink Channels  

作　　者：Weiyu Chen Haiyang Ding Shilian Wang Daniel Benevides daCosta Fengkui Gong Pedro Henrique Juliano Nardelli 

机构地区：[1]College of Electronic Science and Technology,National University of Defense Technology,Changsha 410073,China [2]College of Information and Communication,National University of Defense Technology,Xi’an 710106,China [3]Department of Computer Engineering,Federal University of Ceará,Sobral 62010-560,Brazil [4]State Key Laboratory of Integrated Service Networks,Xidian University,Xi’an 710071,China [5]School of Energy Systems,Lappeenranta University of Technology,Lappeenranta 53850,Finland

出　　处：《China Communications》2020年第6期80-100,共21页中国通信（英文版）

基　　金：supported in part by the National Key R&D Program of China under Grant 2018YFE0100500;the National Natural Science Foundation of China under Grant 61871387,Grant 61861041,and Grant 61871471;the Natural Science Basic Research Program of Shaanxi under Grant 2019JM-019;Academy of Finland via:(a)ee-Io T project n.319009,(b)FIREMAN consortium CHIST-ERA/n.326270,and(c)Energy Net Research Fellowship n.321265/n.328869;the NUDT Research Fund under Grant ZK17-03-08。

摘　　要：In this paper,we investigate the performance of commensal ambient backscatter communications(AmBC)that ride on a non-ortho go nal multiple access(NOMA)downlink transmission,in which a backscatter device(BD)splits part of its received signals from the base station(BS)for energy harvesting,and backscatters the remaining received signals to transmit information to a cellular user.Specifically,under the power consumption constraint at BD and the peak transmit power constraint at BS,we derive the optimal reflection coefficient at BD,the optimal total transmit power at BS,and the optimal power allocation at BS for each transmission block to maximize the ergodic capacity of the ambient backscatter transmission on the premise of preserving the outage performance of the NOMA downlink transmission.Furthermore,we consider a scenario where the BS is restricted by a maximum allowed average transmit power and the reflection coefficient at BD is fixed due to BD’s low-complexity nature.An algorithm is developed to determine the optimal total transmit power and power allocation at BS for this scenario.Also,a low-complexity algorithm is proposed for this scenario to reduce the computational complexity and the signaling overheads.Finally,the performance of the derived solutions are studied and compared via numerical simulations.

关 键 词：power-domain NOMA ambient backscatter communications IOT wireless-powered devices optimization 

分 类 号：TN929.5[电子电信—通信与信息系统]