中文摘要：

对基金会现场总线FF（foundation fieldbus）集中式介质访问控制方式中的周期信号所采用的总线调度算法进行了分析，并提出了改进算法。该算法首先对每个子节点总线占用时间进行分割，通过增加average判断环节使得微周期分配更加均匀；然后，采用最终节点自动调度环节减少了最终节点的调度次数，节省了系统开销，并利用改进算法制定了调度表，提出了调度表验证公式，搭建了实验平台模拟总线调度；最后，通过实际案例对比分析了原算法与改进算法的使用特点。结果表明：改进算法生成的调度表具有更大的调度范围和更高的时间利用率。

英文摘要：

This paper analyzes the dispatching algorithm of periodic signal in the foundation fieldbus and proposes an improved algorithm. The algorithm aims at dividing the time of each node, adding average judgements to make the micro-cycle distribution more uniform and using the last-node-automatic dispatching means to cut down its number of dispatches to save the cost of the system. Finally, real examples are used to contrast the old algorithm and the improved one. The results show that the improved algorithm has a bigger dispatching range and higher time rate of use.