The Research And Design Of Temperature And Humidity Data Acquisition System Based On Wireless Sensor Network

The Chinese agriculture which is under the social information-based push, is developing quickly toward information-based direction of agriculture in the past ten years. The digital agriculture technologies that are its core have already followed the research development stage.Wireless sensor network is a new short-range, low complexity, low power, low data rate and low price transmission in a wireless personal area network. Apply it in the agriculture produces in order to collect the temperature and humidity of the soil. Then, the wireless temperature and humidity data acquisition system is constituted. It doesn't need to arrange the line and the collection node is vivid establish and large-range. So the system will be a first choice in the future.Firstly the structures of wireless sensor network, protocol stack, characteristics and its correlative key are introduced in the thesis. It includes the IEEE802.15.4 specifications and the ZigBee protocol stacks. Then, it introduces the total system design and the software and hardware research of wireless sensor network agriculture temperature and humidity data acquisition system. The Freescale MC9S08GT60CFB MCU is a low power processor based on S08 core and special for wireless sensor network nodes. The RF chip of MC13192 which is low power, 2.4GHz ISM Frequency includes the IEEE802.15.4 protocol standard, the work in the open 2.4GHz frequency band, supports coordinated, the star and the lattice network architecture. Serial outside supposes the connection with MCU through four (SPI) to connect. The SHT71 chip which is made in Switzerland Sensirion Company is used for the temperature and humidity data acquisition. It uses the patent the CMOSens technology, guarantees the product to have the extremely high reliability and the remarkable long-term stability.The developing and debugging environment of the front system micro-controller is Code Warrior Development Studio. Code Warrior^TM is completely used in the programming application of the hardware bring-up integrated development environment. Code Warrior includes all the main tools such as IDE, the compiler, the debugger, the editor, the link, the assembly program and so on which are necessary to construct the plat form and be applied. The PC application procedures of the terminal monitors in this system are developed by using Visual C++.After test and application experiments, the wireless sensor network agriculture temperature and humidity data acquisition system shows good performance in low power consumption and stability, and is well qualified to be applied.