崔立尉++杨申浩

摘 要 无线传感反应器网络（WSANs）中现有的报文投递方案可靠性不足，不适用于数据率互不相同的网络场景.为此，提出一种基于可靠性最大化的报文实时投递方案.报文投递问题被分解为两个子问题：基于子周期的时隙分配问题和基于时隙的传输调度问题.第1个子问题被转化为一个线性整数规划问题，并给出一种具有多项式时间复杂度的求解方法.对于第2个子问题，文中证明是否存在最优可行调度取决于求解前一子问题时获得的时隙分配向量中的元素次序，然后给出一种可行时隙分配方案求解算法.仿真结果表明，本文算法可保证每个设备即使在不同的报告周期内也可实现基本相同的报文投递率，这一特性对于维持控制系统的稳定性具有重要作用.

关键词 无线传感反应器网络；流量；非线性整数规划；可靠性；时隙；报文投递率；稳定性

中图分类号 TP393 文献标识码 A 文章编号 10002537（2016）010085010

A RealTime Delivery Scheme of Packet Based on Reliability

Maximization in Wireless SensorActuator Networks

CUI Liwei1，2， YANG Shenhao3*

（1. School of Information Management and Computer Technology， Inner Mongolia Agricultural University， Baotou 014109， China；

2. School of Information Engineering， Inner Mongolia University of Science and Technology， Baotou 014010， China；

3. School of Computer Science and Technology， Tsinghua University， Beijing 100083， China）

Abstract The existing packet delivery schemes have a low reliability in wireless sensoractuator networks （WSANs）. Hence， these schemes are not suitable for networks with heterogeneous traffic rates. To solve this problem， a realtime delivery scheme of packet based on reliability maximization is proposed. The packet delivery problem is decomposed into two subproblems： subperiodbased slot allocation and slotbased transmission scheduling. The former subproblem is formulated as a linear integer programming problem， and we present a solution with polynomialtime complexity. For the latter subproblem， we demonstrate that the existence of a feasible optimal schedule depends on the order of the elements in the slot allocation vector produced by solving the former subproblem， and then an algorithm is designed to compute a feasible slot allocation that sustains a realizable schedule. Simulation results demonstrate that our scheme ensures each device has almost the same packet delivery rate in different report periods， which is important for maintaining the stability of control systems.

Key words wireless sensoractuator networks； traffic； nonlinear integer programming； reliability； slot； packet delivery rate； stability

基于无线传感反应器网络[1]（WSANs）的工业自动化技术在降低部署成本和提高系统灵活性方面具有巨大优势，因此在近些年引起了研究和工业领域的大量关注.为了促进WSANs在工业领域的应用，人们已经提出了3套国际标准[23]：WirelessHART，ISA 100.11a和IEEE 802.15.4e.这些标准均采用基于IEEE 802.15.42006标准且支持2.4 GHz ISM频段16个信道的低功率无线电技术.然而，采用这些低功率无线电技术的设备非常不可靠，且链路质量往往具有时变特性，尤其是恶劣环境下更是如此，比如存在大量噪声且对象……