An Advanced Intelligent Control System Used In Greenhouse Based On WSN

Since China is a great agricultural country with long history, the basic national condition dicides that issues concerning agriculture, countryside and farmers to become a serious problem in economic and social development process. Agricultural production efficiency will become an important subject in modern agricultural development. At the same time, as a important form of farming, greenhouse develops rapitly in our country, and up to now, we have the world's largest greenhouse area. Growth in production efficiency depends on advanced agricultural equipment and automatic technology, which help collecting real-time imformation and controlling to keep a best growing environment for the plants in the greenhouse. Extensive application based on PLC, MCU or field bus technique in the market which are all wired control system, have limitations in wiring or price or scalability.Having the disadvantages of the systems above in mind, another control system based on wireless communication is brought out without considering of the precision farming method using GIS and GPS in western countries, which using WSN based on ZigBee technology. This control system uses WSN to collect real-time farming imformation and uses ZigBee to form the network and do data communication, while routers choose best communication ways according to target address and send the information to PCcontrol terminal. Then PC will give control command according to expert database and send the commands to base station in the greenhouse to operate peripheral equipments. The intelligent control system based on WSN is introduced in detail in this article, which is consist of three parts. One part is sensor nodes (also called terminal instruments) distributing in the greenhouse which are used to collect argricultural information such as temperature, humidity, photometric quantity and so on. The second part is the greenhouse base-station (also called router nodes), which is used to gather the information, transmit them and to operate electrical equipment. The last part is terminal (also called pan coordinator), which is used to gather the information and communicate with virtual control platform in PC.In terms of adaptive network forming and data communication routing algorithms choosing, an adaptive routing choice algorithms based on tree topology used in ZigBee network in this system is analyzed. This algorithm is based on LEACH algorithm, and the disadvantage of which is analyzed and improved in this article. Simulating results show that, after improving, energy consumption of the whole network is reduced and becomes more balanced, thus the lifecycle of the network is greatly lengthened.After testing, the architecture of the control system designed in this paper is quite reasonable and each module circuit works well. The whole system is stable and of good properties and low price, which reaches every expected standards in advance.