基于ZigBee和PDA的农田信息无线传感器网络

为了实现农田信息的实时采集、处理与可视化，缩短数据采集和处理间的时差，开发了基于ZigBee和PDA的农田信息无线传感器网络。系统由集成ZigBee协调器的PDA和带传感器的路由节点组成。通过无线传感器网络，用户手持PDA可实时动态访问田间信息，并控制传感器的供电电源开关，以节省功耗。采集的田间信息包括土壤水分、土壤温度、土壤电导率、空气温湿度。其中土壤温度、空气温湿度传感器为数字式传感器，土壤水分、土壤电导率传感器为模拟传感器。节点通信距离试验表明，正常工作条件下，40 m距离的丢包率只有0.092，满

Development of wireless sensor network of field information based on ZigBee and PDA

In order to achieve real-time acquisition, processing and visualization for field information, and shorten the time difference between data acquisition and processing, a wireless sensor network based on ZigBee and PDA was developed. The system consisted of a PDA with a ZigBee coordinator and router nodes with sensors. Via the wireless sensors network, the field information could be dynamically accessed in real time by PDA and the power supply for sensors could be controlled to save power consumption. Here the field information refers to soil moisture, soil temperature, soil electrical conductivity, air temperature and humidity. Soil temperature sensor and air temperature and humidity sensor were digital sensors, while soil moisture sensor and soil electrical conductivity sensor were analog sensors. Node communication test for different distances showed that under normal operating conditions, the packet loss rate of 40 m as only 0.092, met the requirements. In the hop test, the information could be sent from the farthest node to PDA through the self-organizing network accurately. It demonstrates that the network works stably.