摘要
以智能反射面(intelligent reflecting surface,IRS)辅助的无线携能通信(simultaneous wireless information and power transfer,SWIPT)系统为背景,研究了该系统中基于能效优先的多天线发送端有源波束成形与IRS无源波束成形联合设计与优化方法。以最大化接收端的最小能效为优化目标,构造在发送端功率、接收端能量阈值、IRS相移等多约束下的非线性优化问题,用交替方向乘子法(alternating direction method of multipliers,ADMM)求解。采用Dinkelbach算法转化目标函数,通过奇异值分解(singular value decomposition,SVD)和半定松弛(semi-definite relaxation,SDR)得到发送端有源波束成形向量。采用SDR得到IRS相移矩阵与反射波束成形向量。结果表明,该系统显著降低了系统能量收集(energy harvesting,EH)接收端的能量阈值。当系统总电路功耗为−15 dBm时,所提方案的用户能效为300 KB/J。当IRS反射阵源数与发送天线数均为最大值时,系统可达最大能效。
Intelligent reflecting surface(IRS)-assisted simultaneous wireless information and power transfer(SWIPT)system is set as research background.Joint design and optimization of energy-efficiency priority based active beam-forming at multi-antenna transmitter and passive beamforming at IRS were investigated.The optimization objective was to maximize minimum energy-efficiency,which was subject to transmitter power control,energy constraint at energy harvesting(EH)receiver and IRS phase shift constraint.Alternating direction method of multipliers(ADMM)was implemented to solve this non-linear non-convex optimization problem.Firstly,the fraction objective function was transformed via Dinkelbach’s approach.Singular value decomposition(SVD)and semi-definite relaxation(SDR)were applied to obtain active beam forming vector at transmitter.Simulation results indicate that,IRS assisted SWIPT could significantly reduce energy threshold at EH receiver.The achievable energy-efficiency of the proposed strategy is 300 KB/J when total circuit power consumption is−15 dBm.Maximum energy-efficiency can be achieved with the maximum numbers of passive reflecting elements and transmitter antennas.
作者
许晓荣
朱薇薇
包建荣
朱卫平
冯维
姚英彪
XU Xiaorong;ZHU Weiwei;BAO Jianrong;ZHU Weiping;FENG Wei;YAO Yingbiao(School of Communication Engineering,Hangzhou Dianzi University,Hangzhou 310018,China;Department of Electrical and Computer Engineering,Concordia University,Montreal H3G1M8,Canada)
出处
《电信科学》
2022年第1期36-46,共11页
Telecommunications Science
基金
国家自然科学基金资助项目(No.U1809201)
国家留学基金委公派访问学者资助项目(No.202108330152)
浙江省自然科学基金一般项目(No.LY19F010011)
浙江省教育厅科研项目(No.Y202044430)
杭州电子科技大学“优秀骨干教师支持计划”人才项目。
关键词
智能反射面
无线携能通信
能效优先
波束成形
交替方向乘子法
intelligent reflecting surface
simultaneous wireless information and power transfer
energy-efficiency priority
beamforming
alternating direction method of multipliers
