面向农田复杂时变环境的无线传感器网络高效传输与虚拟化关键技术研究

In time-varying agricultural wireless sensor network (WSN) monitoring application, there are many characteristics, such as wide monitoring area, large scale network, random distribution, heterogeneous nodes, complex time-varying signal environment and varying network topology, which has a tremendous impact on coverage and network connectivity. Since the nodes around of sink have many data to transmit, energy hot spots have been formed. There are some overlap between nodes in both time and space, which causes data redundancy. In the current study, there are some problems including optimization complexity and limited computing ability of nodes .In order to resolve these problems, network topology control mechanism based on prediction and feedback scheduling will be studied. In this study, data transmission and control method based on mobile node would be researched, which could improve efficiency of data communication and network coverage. We will propose a new farmland wireless sensor network architecture based on software defined networking (SDN). In one word, our study will benefit the efficiently communication of WSN for complex time-varying environment of farmland.

在农田复杂时变环境下无线传感器网络监测中，存在监测面积广、网络规模大、节点分布不均、多级异构以及作物生长引进的信道环境复杂多变等特点，网络节点间拓扑连接关系动态变化，对网络连通覆盖性影响巨大。由于汇聚节点周边的节点需承担大量数据转发任务，形成能耗热点，存在数据冗余。现有垂直网络协议架构，不同角度的优化方案难以实现有机整合，且规模化网络控制算法的复杂度受限于节点计算资源。针对以上问题，研究农田复杂时变环境网络拓扑预测反馈调度机制，为网络连通覆盖与可靠高效地数据传输提供保证；考虑结合移动节点的数据传输控制策略，有助于提高网络连通覆盖性能与数据传输效率；研究动态环境下的感知融合策略，减少数据传输量，提高传输有效性；建立基于软件定义网络的农田无线传感器新型网络架构，实现传感网络的控制与转发解藕合，建立虚拟平台层为农田多源环境因子监测与自动化生产控制提供服务和参考，为实现农业数字化生产提供有力支撑。

按照研究计划书完成了研究任务，针对农田复杂时变环境无线传感器网络的网络拓扑控制方面，基于概率感知建立了节点空间拓扑模型，提出一种基于时空域复用的网络频谱交错接入拓扑控制方法；针对农田复杂环境，引入移动节点，建立基于移动节点的抗干扰模型，提出了一种能耗与时延的移动节点路径优化算法和数据传输覆盖控制策略；提出了移动sink路径规划与子网路由方法、面向大规模农田紧时延约束的移动sink节点接入方法、基于多视角技术的农田WSN数据融合方法以及基于作物生长环境关联的压缩感知方法等； 提出了基于能量传输的中继网络模型优化算法，对能耗与时延的进行联合优化；提出了一种基于SDN的无线传感网络架构，并设计了北向接口和南向接口模块以及控制器。研究成果可应用于农业物联网、智慧农业以及农业无人机等领域。