农田土壤含水率监测的无线传感器网络系统设计

为解决传统土壤含水率监测中所存在的监测区域面积小、采样率低等问题，设计和开发了基于无线传感器网络技术的土壤含水率监测系统，包括10个传感器节点，1个簇首和1个基站节点，可按任意时间间隔全自动地采集、处理、传输和存储地表以下4个不同土层土壤含水率变化状况；各类节点采用TinyOS操作系统，节点间通信遵循ZigBee协议；含水率测量采用EC-5传感器；太阳能供电模块的供电能力满足传感器节点及簇首的能耗需求；进行了数据包传输率试验，10个传感器节点中有7个的数据包正确传输率高于90%，1个节点的数据包正确传输率为89.2%，2个节点的传输率低于70%。造成2个节点数据包传输率较低的主要原因是太阳能供电电路制作，通过更换电路板解决了该问题。试验结果表明，系统能够实现稳定的数据传输，适合农田土壤含水率的实时监测。

Design of wireless sensor network system based on in-field soil water content monitoring

For finding a way to retrieve,transmit and store data in large-scale,full-coverage soil water content monitoring,a wireless sensor network system was developed and tested.The system was composed of ten sensor nodes, one central node to collect data from the sensor nodes and one base node connected to a PC to retrieve,store,and present the data.Soil water contents at four depths,i.e.,5.00,15.24,30.48 and 60.96cm below soil surface,were continuously monitored.TinyOS and ZigBee were applied as operation system...