针对林区局地环境监测实时性差、长期监测困难等不足,设计并实现了一种基于ZigBee无线传感器网络的林区局地环境监测系统。系统运用无线网络协议ZigBee搭建无线传感器网络,结合GPRS通讯技术将获取的数据发送至监控中心,实现数据的实时显示、存储、分析与可视化。系统主要由传感节点、路由器、网关与监控中心组成,结构简单实用,节点放置位置灵活,不受地理环境限制,能够较好的监测空气中温湿度、大气压强、光照强度、二氧化碳浓度、土壤含水率等林区关键环境因子。通过太阳能供电系统,采用CC2530和CC2591无线通信模块,并将多传感器集成到传感节点,较好解决了无线传感器网络在林区应用过程中的节点能量不足、通信距离短以及监测参数不全等问题,实现了对林区局地环境的实时监测。试验表明,节点在空旷地方有效通信距离最大可达510.6m,在树林中有效通信距离最大可达177.5m;在太阳能与锂电池共同供电下,节点能量能够自给自足;在组网测试中,整个网络收包率为96.7%,能够满足林区环境监测要求。
In view of lacking real-time and long-term monitoring on local environment of forest region, this study designed and realized a local environmental monitoring system for forest region based on ZigBee wireless sensor network. This system built WSN using wireless network protocol ZigBee, and then, sent the obtained data to monitoring center combining with GPRS communication technology, so as to realize real-time data display, storage, analysis and visualization. This system was mainly composed of sensor nodes, touters, gateways and monitoring center. Its structure was simple and practical. The nodes location was flexible, and free of any geographical environment. The system could better monitor the air temperature and humidity, atmospheric pressure, light intensity, carbon dioxide concentration and soil moisture content, etc. key environmental factors in forest region. Through solar power supply system, it could integrate the multi-sensor into sensor node by CC2530 and CC2591 wireless communication module, and better solve node energy shortage, short communication distance and incomplete monitoring parameters in the process of applying wireless sensor network in forest region so as to realize the real-time monitoring of local environment. This experiment indicated that node effective communication distance in open space could reach 510.6 m, and the effective communication distance in woodland could reach 177.5 m. Under the joint power supply of solar energy and lithium battery, the node energy could be self-sufficient. In the network test, packet reception rate of the whole network was 96.7%, and capable to meet the requirements of environment monitoring in forest region.