无线传感器网络中基于服务质量管理的多目标优化控制

摘要

针对基于无线传感器网络构建的测控系统,为减少无线传感器网络固有的时变传输延时、丢包等现象对系统性能的影响,从提高系统整体性能的角度,提出一种基于网络服务质量QoS(Quality of Service)管理的多目标优化控制策略;该优化控制策略以截止期错失率作为网络QoS评价指标,针对传感器节点和汇聚节点之间的数据传输,利用PID控制器计算所有传感器节点的网络带宽需求,在此基础上,通过求解包含多个目标的最优化问题,实现各传感器节点数据包发送周期的动态调整,使得网络带宽分配适应网络QoS的变化,保证网络QoS维持在一定水平,同时满足系统其它性能指标;初步实验表明了该优化控制策略的合理性、有效性和实用性,可以广泛应用于温室、农田、苗圃等区域.%In order to reduce the impact of inherent network time-varying delay, packet loss and other phenomena on performance of the remote monitoring and control system based on wireless sensor network, the multi-objective optimization control strategy based on network quality of service (QoS) management is proposed from the perspective of improving the overall system performance. For the real-time data transmission from the sensor nodes to the sink node, the proposed optimization control strategy uses the deadline miss ratio as the evaluating index of the QoS, and utilizes the PID controller to calculate the network bandwidth demands for all sensor nodes. Subject to the network bandwidth demands, the multi-objective optimization problem is formulated and solved, then the packet sending period of all sensor nodes is adjusted so that the network bandwidth allocation can adapt to the QoS changes, the QoS is maintained at a pre-determined desired level and other performance criteria is achieved. Preliminary experimentations indicate the rationality, effectiveness and practicability of the proposed optimization control strategy. It can be effectively applied to the greenhouse, the cropland, and the nursery garden, etc.