针对新空口车联网(new radio vehicle to everything,NR-V2X)系统中半持续调度在非周期业务下效率低、不稳定的问题,提出一种基于流量整形的增强型半持续调度机制.以时隙作为调度单位,应对业务的可变分组长度;在传输中预留连续资源,解决业务到达间隔较大导致半持续调度出现的预留中断问题;针对业务到达间隔较小的情况,以动态组包方式和单次资源调度方式,充分利用预留资源并避免不必要的资源更换.仿真结果表明,提出的方案在200 vehicle/km的交通流量下,数据包接收率较半持续调度机制提升约9百分点,较动态调度机制提升约16百分点,有利于提升资源管理的有效性和保证传输的可靠性.
Enhanced semi-persistent scheduling mechanism based on traffic shaping for aperiodic traffic in NR-V2X
Aiming at the inefficiency and instability of semi-persistent scheduling for aperiodic traffic in NR-V2X,we pro-pose an enhanced semi-persistent scheduling mechanism based on traffic shaping.Firstly,the slot is proposed as the sched-uling unit to cope with the variable packet size of the traffic.Secondly,it is proposed to reserve multiple contiguous re-sources in one transmission to solve the reservation break due to long packet arrival interval in semi-persistent scheduling.Finally,in the case of short packet arrival interval,dynamic packet combination and single resource scheduling are pro-posed to fully utilize the reserved resources and avoid unnecessary reselection.Simulation results demonstrate that the pro-posed scheme improves packet reception ratio by about 9%compared with semi-persistent scheduling and about 16%com-pared with dynamic scheduling at a traffic flow of 200 vehicles/km,which contributes to improving the effectiveness of re-source management and ensuring the reliability of transmission.