基于780MHz频段的温室无线传感器网络的设计及试验  

Design and experiment based on wireless sensor network with 780 MHz in greenhouse

作　　者：陈晓栋[1] 郭平毅[1] 兰艳亭[2] 

机构地区：[1]山西农业大学农学院,太谷030801 [2]中北大学信息与通信工程学院,太原030051

出　　处：《农业工程学报》2014年第1期113-120,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：山西省研究生优秀创新项目(20133062)

摘　　要：针对以往农用无线传感器网络（wireless sensor network，WSN）能耗与成本较高、传输性能不理想等问题，该文选用无线射频芯片AT86RF212、单片机C8051F920等，设计了一种工作在780 MHz中国专用频段且与IEEE802.15.4c 标准兼容的无线传感器网络。该文简述了无线传感器网络节点结构，重点介绍了780 MHz 无线传感器网络的硬件设计，并选择北方典型的日光温室作为试验研究环境，通过改变无线收发距离，对780、433和2400 MHz频段的无线传感器网络节点的接收信号强度值（RSSI，received signal strength index）和平均丢包率（PLR， packet loss rate）进行了测试与分析。试验结果表明，3种不同频段的无线收发模块的接收信号强度值RSSI都随着收发距离的增大而减小。在温室内测试，收发距离小于20 m时，3种无线模块的RSSI值相近；收发距离为40～90 m时，7803 MHz模块比433 MHz模块的RSSI值略大，2.4 GHz的RSSI值最小。在温室内收发距离小于90 m的范围内，780 MHz模块和433 MHz模块的丢包率均为0，2.4 GHz模块的最高丢包率不超过5%。在温室间测试，收发距离为50～90 m时，780 MHz模块和433 MHz模块的RSSI值相近；收发距离大于90 m时，780 MHz模块比433 MHz模块的RSSI值大；2.4 GHz模块在温室间收发距离为50～140 m时的RSSI值均小于433、780 MHz。2.4 GHz模块在收发距离大于70 m时出现丢包现象，收发距离大于135 m时丢包率达到100%；温室间收发距离为140 m时，433 MHz模块的最大丢包率为11%，780 MHz的最大丢包率不超过6%。因此，在温室环境监测的应用中，780 MHz频段的无线传感器网络的传输性能表现最佳，且与433 MHz都明显优于2.4 GHz。In recent years, a wireless sensor network （WSN） technique was widely applied in the field of agriculture, which detects, senses, and collects information of various environments or objectives in the network area, and at the same time sends and receives data through wireless and self-organizing multi-hop routing links. Due to the complexity of the agricultural environment and various factors like barriers, weather condition, structure, materials, and the layout of facility agriculture that all affect the WSN communication quality, wireless sensor networks adapt dissimilarly to agricultural environment. Therefore, how to achieve the best networking to different agricultural environment conditions, minimize the cost and energy consumption, and improve the performance of the network transmission turn out to be the key issue in the studying of agricultural wireless sensor networks. Aiming at the problems of previous agricultural wireless sensor networks, such as high cost, high-energy consumption, and non-ideal transmission performance, this paper designed, with chips of AT86RF212 and C8051F920 a new type of wireless sensor network which works on a Chinese dedicated band of 780MHz and is compatible with the IEEE802.15.4c standard for a greenhouse. This paper briefly described the structure of wireless sensor network node, mainly introduced the hardware design of a 780MHz wireless sensor network, and also tested and analyzed the received signal strength index （RSSI） and the average packet loss rate （PLR） of the wireless sensor network node in 433 MHz, 780 MHz, and 2.4 GHz bands by changing the wireless communication distance in a typical northern solar greenhouses working as the experimental environment. The experimental results showed that RSSI of wireless transceiver modules in the three different bands decreased with the increasing of the communication distance. The RSSI values of the three wireless transceiver modules were similar to each other when the communication distance in a greenhouse was less t

关 键 词：无线传感器网络 丢包报失 数据传输 780MHz频段 接收信号强度 

分 类 号：TP274.5[自动化与计算机技术—检测技术与自动化装置] S625.51[自动化与计算机技术—控制科学与工程]