基于NB-IOT随机接入的评估建模与仿真  

Evaluation modeling and simulation based on NB-IOT random access

作　　者：杨磊 龙伟 YANG Lei;LONG Wei(College of Information Engineering,Chengdu Aeronautic Polytechnic,Chengdu 610100,China;College of Computer Science and Engineering,University of Electronic Science and Technology of China,Chengdu 610031,China)

机构地区：[1]成都航空职业技术学院信息工程学院,四川成都610100 [2]电子科技大学计算机科学与工程学院,四川成都610031

出　　处：《计算机工程与设计》2024年第4期1025-1031,共7页Computer Engineering and Design

基　　金：四川省重点实验室开放基金项目(14YYZC0001-210);四川省教育信息化与大数据中心基金项目(DSJ2022081)。

摘　　要：由于NB-IoT传输大部分发生在上行链路,随机接入信道容易成为系统瓶颈。针对此问题,对NB-IoT随机接入信道进行建模,推导出RACH成功概率的精确表达式,量化评估每个覆盖等级中网络配置对系统性能的影响。仿真分析结果表明,利用评估模型对最大前导重传次数、退避窗口大小、子载波数量等参数进行周期性优化,能够有效提高设备接入成功率,降低接入时延。Since most of the NB-IoT transmission occurs in the uplink,the random access channel is easy to become a system bottleneck.Aiming at this problem,the NB-IoT random access channel was modeled,the exact expression of RACH success probability was derived,and the influence of network configuration on system performance in each coverage level was quantitatively evaluated.Simulation analysis shows that using the evaluation model to periodically optimize the parameters such as the maximum number of preamble retransmissions,the size of the backoff window,and the number of subcarriers can effectively improve the device access success rate and reduce the access delay.

关 键 词：窄带物联网 随机接入信道 上行信道 前导重传 覆盖等级 退避窗口 子载波 

分 类 号：TN929.5[电子电信—通信与信息系统]