西红柿温室内无线传感器网络2.4GHz信道传播特性  

Signal Transmission Characteristics of 2.4 GHz Wireless Sensor Network in Tomato Greenhouse

作　　者：韩文霆[1,2] 王毅[1,2] 

机构地区：[1]西北农林科技大学机械与电子工程学院,陕西杨凌712100 [2]西北农林科技大学中国旱区节水农业研究院,陕西杨凌712100

出　　处：《农业机械学报》2014年第10期264-271,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：新世纪优秀人才支持计划资助项目(NCET-12-0473);'十二五'国家科技支撑计划资助项目(2011BAD29B08)

摘　　要：针对西红柿温室环境中无线传感器网络节点部署的要求及其应用环境的特性,以2.4 GHz为载波频率,研究了无线射频信号传播特性和通信距离、天线高度、传输路径等影响因素间的关系。结果表明,无线传感器网络信号在西红柿温室中的衰减符合对数模型;当天线高度固定时,接收信号强度随通信距离的增加总体呈递减趋势,丢包率随通信距离的增加总体呈递增趋势;西红柿温室中天线最宜部署在日光温室中央一列的位置,且西红柿顶部略高于它的位置为放置天线高度的首选,其次为西红柿顶部距地面1.5 m以上的部分,越接近西红柿顶部越好;在上述试验研究的基础上,建立了天线高度、通信距离和接收信号强度之间的关系模型,模型参数A与天线高度、衰减系数n与天线高度之间均呈二次多项式关系。验证试验结果表明:该模型可以较好地预测不同天线高度不同通信距离的接收信号强度,为西红柿温室无线传感器网络的部署提供技术支持。For deploying a wireless sensor network system and studying the channel characteristics in tomato greenhouse,relationships among radio frequency signal propagation characteristics and communication distances,antenna heights,transmission paths were studied with a 2.4 GHz carrier frequency for configuring wireless sensor network in a tomato greenhouse.The results showed that the attenuation of the received signal strength caused by communication distance accorded with a logarithmic model.When the height was fixed,the strength index of received signal tended to decrease and the packet loss rate fluctuated as the distance of transmitter to receiver increased,which was an overall increasing trend.It was the best to place the antennas at a column of central location in greenhouse,in the top of the tomato or above of it,followed at higher place above 1.5 m.The regression analysis results demonstrated that there was a quadratic relationship between the regression parameter A and the antenna height,and there was also a quadratic regression equation between the environmental factor n and antenna height.Besides,a model used for calculating the received signal strength of 2.4 GHz transmitting through tomato greenhouse was constructed.Validation results showed that the model could better predict the received signal strength at different distance point at different height.This research can provide a reference for WSNs application.

关 键 词：无线传感器网络 西红柿 温室 2.4GHz无线通信 信号衰减 

分 类 号：S126[农业科学—农业基础科学]