Data Transmission Technology In Greenhouse Wireless Sensor Network Based On Data Compression

Applying the burgeoning technology of wireless sensor network(WSN) into data transmission of greenhouse,not only can solve the problem of difficult installation and maintenance in traditional wired communication,but also can solve the problem of complicated technology and high cost in traditional wireless communication. However,since it is not easy to replace batteries of the sensor node,wireless sensor networks must minimize energy consumption of sensor nodes to extend the network life cycle.To improve the performance of the wireless sensor network system,this paper has done the two aspects as following in mainly:first,according to the characteristics of the WSN in the measurement and control system of the greenhouse,starting from the design of the network architecture,a divisional management data transmission scheme is proposed that the greenhouse network is divided into multiple subnets: many parallel rails are installed in greenhouse's ceiling,and divided them into some pieces,one circularly movable sink node is installed on each piece;Sink nodes are organizing a small stelliform network automatically in the motion process,and establish a data communication link between sink node and underside sensor nodes periodically;The data link between sink node to base station is directional multi-hop routing are established by every sink nodes on the same rail.Second,according to the data characteristics of the greenhouse,put forward a data compressing method which is suitable for greenhouse application,and applied it to the data transmission in greenhouse WSN.The sink nodes' dynamic topology covering and cooperative divisional management way,on the one hand making the network has the characteristic of variable structure and the capability of self-organization,on the other hand greatly reduced the burden of the sensors' communication task by shorten the communication distance between point to point.The application of data compression technology into this network model can further reduce the sensor's energy consumption.Results indicate that more data acquired more energy can be saved.When the data number are more than sixty,the application of data compression technology can save close to half part of the energy.In addition,on the base of data can be fully transmitted,the application of data compression technology can improve the sensors' data collection frequency over three times,can perfectly improve the constraints of sensor' collection frequency because of the sink nodes can not transmit data timely.