基于优先级分类的工业无线网络确定性调度算法

确定性调度技术对于工业无线网络数据的实时性和确定性传输有着重要意义.本文针对工业无线网络数据流本身存在优先级分类属性的情况,基于多信道时分多址接入(TDMA)技术,在分析高优先级数据流对低优先级数据流造成的链路冲突延时和信道竞争延时基础上,对网络进行调度预处理,进而排除参数不合理的网络,并向网络管理者反馈.对于通过预处理的网络,调度算法优先为高优先级数据流的链路分配时隙和信道资源,而对属于同一类优先级的数据流,提出一种基于比例冲突空余时间的调度方案,在满足可调度性条件的前提下,根据各链路的比例冲突空余时间值从小到大依次分配时隙和信道资源.实验结果表明,所提出的调度算法可以取得较高的网络调度成功率.

Deterministic Scheduling Algorithm With Priority Classification for Industrial Wireless Networks

Deterministic scheduling technology has a significant impact on the real-time and deterministic data transmission in industrial wireless networks. This paper considers the case that end-to-end flows in industrial wireless networks have a property of priority classification, and adopt multi-channel time division multiple access (TDMA) technology. On the basis of analyzing the delays of lower priority flows due to both link conflict and channel contention caused by higher priority flows, there is a pre-processing scheduling for testing networks firstly. Therefore, some networks with unreasonable parameters can be excluded, and this will inform network administrator for further processing. For networks passing the test of pre-processing scheduling, the scheduling algorithm gives preference to allocate time slots and channels to link with higher priority flows. For the flows with the same priority, a scheduling scheme based on proportional deadline and conflict is also presented, which allocates the time slots and channels according to the values of proportional deadline and conflict in ascending order for flows that meet the schedulability condition. Results show that the proposed scheduling method can achieve a higher schedulable ratio.