摘要
随着物联网(IoT,internet of things)的快速发展,机器类型通信(MTC,machine type communication)在生活中的应用大幅增长,机器类设备(MTD,machine type device)的部署也越来越密集。在这种情况下,如果发生断电断网等突发情况,在设备通电的瞬间将会有大规模的MTD同时向基站发起接入,设备接入基站需要完成下行同步、接收系统消息和随机接入(RA,random access)等过程。然而基站所能分配的前导资源是有限的,无法满足如此庞大的接入需求,从而造成网络阻塞,影响设备的接入概率和接入时延。为了减轻RA的接入冲突,提出了一种基于上下行子帧和物理随机接入信道(PRACH,physical random access channel)配置的动态随机接入时机(RO,random access occasion)调整方案,以及针对时延要求高的部分MTD分配特定的前导资源,仿真结果表明该方案能够有效提高系统的吞吐量,降低设备的接入时延。
With the rapid development of the internet of things(IoT),the application of machine type communication(MTC)in life has grown substantially,and the deployment of machine type devices(MTD)has become more and more intensive.In this case,if there is an unexpected situation such as a power outage and a network failure,a large-scale MTD will initiate access to the base station at the same time when the device is powered on.When the device accesses the base station,it needs to complete the downlink synchronization,system message receiving,random access(RA)and other processes.However,the preamble resources that can be allocated by the base station are limited and cannot meet such a huge access demand,which causes network congestion and affects the access probability and access delay of the device.In order to alleviate the access conflict of RA,a dynamic random access occasion(RO)adjustment scheme was proposed based on the uplink and downlink subframes and physical random access channel(PRACH)configuration,and time-based part of the MTD with high delay requirements allocates specific preamble resources.The simulation results show that this scheme can effectively improve the throughput of the system and reduce the access delay of the device.
作者
景少雄
袁悦
熊家炜
王军选
JING Shaoxiong;YUAN Yue;XIONG Jiawei;WANG Junxuan(School of Communications and Information Engineering,Xi'an University of Posts&Telecommunications,Xi’an 710121,China)
出处
《物联网学报》
2022年第2期88-94,共7页
Chinese Journal on Internet of Things
