| Continuous, real-time, accurate monitoring on soil water content is significance tofine irrigation and rational utilization of water resources research, especiallyin the agricultural production in the western arid and semi-arid regions. For finding a way toretrieve, transmit and store data in large-scale, full-coverage soil water content monitoring, awireless sensor network system was developed and tested. Zigbee-based monitoring system inthe field of information data collection, transmission and other issues of convergence wereresearched. Main contents and conclusions are as follows:(1) A Zigbee wireless sensor network with a tree-like topology was designed. It consistsof coordinator, outers and sensor nodes. Field information is collected by sensor nodesdirectly or transmitted through a router to the coordinator. Coordinator sends the informationthrough the RS-232serial port to the PC, and the information are displayed and stored. Thewireless sensor network implements the data acquisition and collection in the close range offield for remote monitoring system. All its proceedings are carried out by wirelesstransmission.(2) Considering the system's low power consumption and reliability, CC2430RF chipwas used as the core processor in sensor node and FDS-100low-power and low-cost soilmoisture sensor was applied.(3) Zigbee2006Z-Stack protocol was researched, and applications were also developed,including network formation, the system binding, data acquisition, data transmission, datareception and so on. Meanwhile the software system implements data acquisition,transmission and collection. The low-power sleep mode of RF chip CC2430and the selectivemeasures for sending data were used to reduce node energy consumption, which extendsbattery's life and replacement cycle.(4) The development of the host computer interface design, which shows farmland soilwater content data and data storage, is based on VC++6.0. Host computer softwaredevelopment includes interface design and incident response program design. Incidentresponse procedures includes serial connection, data received, file creation and data retention.(5) Experimental results show that the field monitoring system can monitor real-timesoil water content information, and sensor node has a good energy saving effect, Which cansatisfy the requirements of multi-point measurement, mobility, convenience in the field information monitoring process. It also solves inconvenience wiring problem caused bycomplex environmental factors in monitoring system. |
