RSSI based location estimation in wireless sensors networks

Location estimation of sensor nodes is a key component in many wireless sensor networks´ (WSN) applications such as target tracking, rescue operations, disaster relief and environmental monitoring. The accuracy of the localization algorithm is a vital component to the success of the localization technique. The RSSI ranged based localization algorithm is a simple and cost effective localization technique that relies on measuring the Receive Signal Strength Indicator (RSSI) for distance estimation. In this paper we present experimental results that are carried out to analyze the sensitivity of RSSI measurements in an outdoor and indoor environment. A calibration model that characterized the RF radio channel will be derived and used for distance estimation. The validity of the estimated distance will be verified to track the position of a sensor node within an indoor environment. The results of this study reveal the feasibility of RSSI based localization algorithm in designing correct real-time position monitoring system.