Wireless Sensor Network for Soil Moisture Applications

The development of a wireless sensor network for soil moisture measurements, in a wide reference area of 10 x 10 km², is described in this work. Some automatic measurement stations were strategically placed following soil homogeneity and land uses criteria. These stations include acquisition, conditioning and communication systems. The electronics are operated by a solar panel fed battery, in order to allow them to operate autonomously. The collected data are then transmitted by radio links, with link ranges up to 8 km. A standard PC is used to control the whole network and store the data. This computer also allows accessing the data via Internet for its subsequent analysis. Even though the specific application was the characterization of a reference area, in order to use it in campaigns of calibration and validation of the space mission SMOS (Soil Moisture and Ocean Salinity), the system is easily extensible to other climatic measurements as well as for other zones of interest.