RF characteristics of Mica-Z wireless sensor network motes

Abstract

This thesis investigates the RF characteristics of Mica-Z wireless unattended sensor networks for military and commercial applications. Several experimental configurations were designed and experiments carried out to observe and analyze the behavior of the Mica-Z sensor network. The Mica-Z moteâ s propagation characteristics and network performance were measured under near free-space, indoor and outdoor environments to provide a comprehensive perspective of typical sensor network characteristics. Link-break and re-association distances with their corresponding RF power measurements were recorded to determine the Mica-Zâ s range characteristics under these different operating environments. Power loss exponents were also estimated to provide Mica-Z users a faster and more convenient way to estimate operating ranges in the different environments. A graphical numeric electromagnetic code (GNEC) simulation was also used to investigate some of the possible improvements that could be made to the existing Mica-Z antenna design to enhance the performance of the sensor network. This thesis substantiates the difficulties of operating such sensor networks in the most hostile environments. Although the measurements and analyses demonstrated that controlled deployment was possible to some extent, the effectiveness of deployment remains challenging especially for random ad-hoc deployment.