Localization and Time-Synchronization in Wireless Sensor Networks for Precision Agriculture

Wireless sensor networking is a promising new technology for precision agriculture. Utilization of wireless sensors to monitor agricultural production will require the networks to consist of inexpensive devices with limited capability. Localization, which consists of estimating the positions of sensor nodes that are not equipped with GPS, and time synchronization between the nodes of a network, are two main challenges that need to be tackled. It turns out that these two problems are special cases of estimation from relative measurements. We discuss how to obtain accurate estimates of location and time, how to compute these estimates in a distributed manner, and summarize the effect of network topology on the achievable accuracy.