摘要
Intelligent reflecting surface(IRS),with its unique capability of smartly reconfiguring wireless channels,provides a new solution to improving spectrum efficiency,reducing energy consumption and saving deployment/hardware cost for future wireless networks.In this paper,IRS-enabled spectrum sharing is investigated,from the perspectives of interference modeling,efficient channel estimation and robust passive beamforming design.Specifically,we first characterize the interference in a spectrum sharing system consisting of a single primary user(PU)pair and a single secondary user(SU)pair,and extend it to the large-scale network by leveraging the Poisson point process(PPP).Then,we propose an efficient channel estimation framework based on decoupling the cascaded IRS channels.Moreover,the tradeoff between spectrum efficiency and energy efficiency is derived from the view of channel estimation accuracy.Finally,we discuss the robust passive beamforming design in presence of imperfect channel estimation and nonideal/discrete phase shifts.It is hoped that this paper provides useful guidance for unlocking the full potential of IRS for achieving efficient spectrum sharing for future wireless networks.
基金
supported by the National Natural Science Foundation of China under Grant No. 62171461
Natural Science Foundation on Frontier Leading Technology Basic Research Project of Jiangsu under Grant No. BK20212001
supported by the Macao Science and Technology Development Fund,Macao SAR,under Grant Nos. 0119/2020/A3, SKL-IOTSC-2021-2023 and 0108/2020/A
the Guangdong NSF under Grant No. 2021A1515011900
the Open Research Fund of National Mobile Communications Research Laboratory,Southeast University,under Grant No. 2021D15
