基于无线传感器网络的温室大棚环境监测系统设计

摘要

According to the problems of difficult wiring, low flexibility and high cost in greenhouse environment monitoring system at present, we constructed the greenhouse environment monitoring system based on wireless sensor network ( WSN) .The sensing node and gateway node were designed.The sensor node in this system is used to collect environmental parameter.Data were sent to gateway node through wireless sensor network.The gateway node transmit data to remote monitoring platform.The microprocessor modules of node hardware used MSP430F149 Single Chip Microcomputer to process and control data.Wireless communication module is composed by nRF905 radio frequency chip and its peripheral circuit, which were used to transmit and receive the data.Sensor module used AM2301 sensor to measure data.Circuit of power module was composed of LT1129-3.3, LT1129-5 and Max660, so as to provide 3.3 and ±5 V power supply.Wireless routing proto-col in the node was developed by C language, and realized the node data acquisition and treatment, rules retransmission and Tele transmission and so on.Remote monitoring software used NET.ASP, HTML and C# for development, which provided visual and intuitionistic WEB mode remote data management platform.Networking testing of this system was carried out in greenhouse in Xining City of Qinghai Province.Results showed that the system was stable and reliable.The average packet loss rate was 2.4%, which effectively solve the problems in greenhouse environment monitoring system, and met the requirements for application of greenhouse cultivation environment monitoring.%针对目前温室大棚环境监测系统存在布线困难、灵活性低和成本高等问题，构建了基于无线传感器网络（WSN）的温室大棚环境监测系统，并重点对传感节点和网关节点进行了设计。该系统的传感器节点负责对环境参数进行采集，并通过无线传感器网络将数据发送到网关节点，网关节点再向远程监测平台传输数据。节点硬件的微处理器模块采用MSP430F149单片机进行数据处理和控制；无线通信模块由nRF905射频芯片及其外围电路组成，负责对数据进行传输和接收；传感器模块采用AM2301传感器进行数据测量；电源模块以LT1129－3．3、LT1129－5和Max660组成的电路提供3．3和±5．0 V电源。节点的无线路由协议和时间同步算法均采用C语言开发，实现节点数据采集与处理、规则转发和远程传输等功能。远程监测软件采用NET．ASP、HTML和C＃开发，为用户提供形象直观的Web模式远程数据管理平台。该系统在青海省西宁市温室大棚进行了组网测试，结果表明系统运行稳定可靠，网络平均丢包率为2．4％，有效解决了温室环境监测系统中存在的问题，满足温室大棚栽培环境监测的应用要求。