Sensing with Wireless Sensor Networks

Wireless sensor networks (WSNs) are a group of interconnected autonomous sensor nodes that use wireless communication technology. Their goal is to monitor physical or environmental conditions and to transmit their data cooperatively to a base station. The WSNs are used widely and have proved particularly useful in difficult environments where wired networks cannot be deployed. This feature together with their ability to adapt to changing environments, and the low cost of installing and maintaining them are the main characteristics that make them good sources of data in agricultural settings. The use of WSNs can provide farmers with valuable information on field properties, which can help them understand field variability and make better and quicker decisions on applying agricultural inputs such as pesticides, irrigation and fertilizers. Information on WSNs presented in this chapter is designed to provide potential users with the main concepts of WSNs and the ability to select the best WSN properly for their needs. The chapter is divided into three sections: (5.1) Concepts of Sensing with WSNs; (5.2) Applications of WSNs in Agriculture and (5.3) Conclusions and Future of WSNs. Section 5.1 presents the importance of WSNs. Most of the available wireless communication standards and protocols are described and their performance is compared. Section 5.2 presents the sensors and electronics that are available in the market. Furthermore, it describes and presents examples of applications of WSNs in agriculture such as irrigation, fertilizer application, pest management, crop and weather monitoring. Section 5.3 discusses the importance of WSNs for agricultural applications. Use of WSNs will improve overall agricultural system performance and will propel us closer to precision agriculture and smart farming, by providing the data that will allow farmers to apply the right amount of resources at the right time and in the right place. Future improvements to WSNs will make them more efficient, less complex and self-healing.