中文摘要：

针对802.15.4 MAC层数据包平均服务时间优化问题,提出了一个基于超帧结构的节点状态转换机制,并分析了数据包服务时间定义;然后通过对节点状态的马尔可夫链建模,推导出网络主要状态的稳态概率和数据包服务时间的分析式;最后研究了参数NB、BE、SO对节点稳态概率数据包服务时间的影响。研究结果表明,与其他具有休眠的节点模型相比,数据包平均服务时间平均降低了2.3%。模型较好地描述了802.15.4网络节点的工作特点,且均衡的协议参数配置可以改善数据包的传输性能,为提高网络的实时性提供应用参考。

英文摘要：

Aiming at the optimization problems of the data packet average service time of 802. 15. 4 MAC layer,this paper proposed a conversion mechanism of node state based on super frame structure,and analyzed the definition of the data packet average service time. After that,it derived the steady-state probability of the main state and the formula of the data packet average service time by establishing the model of Markov chain on the state of the node. At last,this paper researched the influence of the protocol parameters such as NB,BE,SO to the data packet service time of the steady-state probability. The research results show that,the data packet average service time is reduced by 2. 3%,compared with other dormant node models. The model describes the working characteristics of 802. 15. 4 network nodes very well. The balanced configuration of protocol parameters can improve the packet transmission performance. And the model can provide the reference for raising the real-time performance of the network.