基于PDMA的5G NR低功耗大连接免调度算法

PDMA-based grant-free strategy of resource allocation for 5G NR low power and massive connectivity

在5G低功耗大连接场景下,一个小区内存在着数量非常多的UE,并且每个UE传输速率、每次传输的传输块并不大,所以PDCCH信道能够承载的DCI数量就成为增加UE连接数的主要瓶颈,为了降低对PDCCH的DCI数量需求,基于上行的基于PDMA的非正交多址接入技术和免授权调度结合的传输方案,提出此资源分配方案,通过初步系统仿真,相同参数情况下频谱效率可提高到LTE的200%~300%,上行调度过程占用控制信道资源至少降低30%。此外,对于发生碰撞的UE,初传均为免授权,重传时采用授权调度,通过优化PDCCH搜索空间,UE能耗至少降低14%。

Low Power And Massive Connectivity,one of a typical scenario of the fifth generation of wireless communication,means million-level connection numbers of UE,captured by lower transmission rate and smaller size of transport block.These requirements are limited by quantities of DCI.So we proposed Pattern Division Multiple Access along with Grant-free in uplink.By preliminary systematic simulation,comparing to LTE with same enviromental parameter,overhead of PDCCH DCI could cut down 30% at lowest.What＇s more,by optimizing the PDCCH search space,for UEs collision with other UEs,whose retransmission is scheduled by grant-based,the power consumption of UE could cut down more than 14%.