RSS-based localization for wireless sensor networks in practice

Many factors have to be considered when RSS-based localization applications are designed, starting from selection of the proper propagation model, which has to represent in a relatively accurate way the interaction between the RF signal and the environment. The topology parameters, such as the number of beacons, the beacons´ heights from the ground and the appropriate distance between the beacons, have to be also evaluated to satisfy the localization requirements. In the present work¹ we investigate the feasibility of sensor node localization by exploiting the inherent resources of the WSN technology, specifically the RSS of the exchanged messages. It is demonstrated that the RSS can be used for outdoor localization under well-defined topology constraints. Localization techniques, topology parameters and factors influencing the localization accuracy are combined in simulation examples to evaluate their impact concerning the positioning accuracy. Furthermore, the RF propagation model and the topology parameters being identified are validated in real outdoor localization experiments.