基于终端自主侦听的NR Sidelink非授权接入机制  

Terminal Autonomous Sensing Based Access Mechanism for NR Sidelink on Unlicensed Spectrum

作　　者：朱振杰 崔琪楣[1] 张雪菲 陶小峰[1] ZHU Zhenjie;CUI Qimei;ZHANG Xuefei;TAO Xiaofeng(School of Information and Telecommunication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]北京邮电大学信息与通信工程学院,北京100876

出　　处：《无线电通信技术》2023年第2期292-299,共8页Radio Communications Technology

基　　金：国家重点研发计划(2020YFB1806804)。

摘　　要：5G新空口(New Radio, NR)定义了侧行链路(Sidelink, SL)模式2资源分配机制,使用户能自主选择预留资源进行数据传输,以满足基站覆盖范围外终端间直接通信的需求;随着移动通信技术的快速发展,智能终端间直接通信对于速率的要求越来越高,有限的授权频谱成为限制速率的瓶颈,使用非授权频段可以缓解授权频谱资源短缺的问题,进一步提升网络的传输速率;非授权频谱中的NR(NR in the Unlicensed Spectrum, NR-U)采用先听后说(Listen Before Talk, LBT)接入非授权信道,LBT不确定性会引起NR SL用户接入预留资源失败,带来额外的传输时延。针对上述问题,提出一种基于终端自主侦听的非授权接入方法,通过配置候选预留子信道资源,提升了模式2资源分配机制下NR SL用户采用LBT机制接入非授权信道的成功率。仿真结果表明,所提机制能有效提升NR SL系统在非授权频段的性能。5G NR defines Sidelink(SL)mode 2 resource allocation mechanism,enabling users to autonomously select reserved resources for data transmission to meet the needs of direct communication between terminals outside the coverage of the base station.With the rapid development of mobile communication technology,direct communication between intelligent terminals requires higher and higher data rate,and the limited licensed spectrum becomes the bottleneck of data rate.Using unlicensed spectrum can alleviate the shortage of licensed spectrum resources and further improve the transmission rate of the network.NR-U uses Listen Before Talk(LBT)to access unlicensed spectrum.The uncertainty of LBT will cause NR SL failing to access reserved resources,resulting in additional transmission delay.To solve above problems,an access method based on terminal autonomous sensing is proposed in this paper.By con-figuring candidate reserved sub-channel resources,the channel access rate for NR SL users on unlicensed spectrum under the Mode 2 resource allocation mechanism is improved.Simulation results show that the proposed mechanism can effectively improve the perform-ance of NR SL system in the unlicensed frequency band.

关 键 词：新空口侧行链路 非授权频谱 资源分配机制 先听后说 

分 类 号：TN929.5[电子电信—通信与信息系统]