Consistency analysis of RSSI measurement for distance estimation of Wireless Sensor nodes

Wireless Sensor Devices are becoming more attractive as a sensor platform compared to wired sensor device because of the ease of installation and freedom in sensor placement. The field of Wireless Sensor Network (WSN) has been increasing with the advancement of modern science and technology. In order to determine the location of sensor nodes, lots of localization algorithm have been established and proposed by the researchers. Since the Received Signal Strength Indicator (RSSI) is assumed to be a strong parameter, most of researches have been worked out for localization algorithm using RSSI. But it is found that lots of irregular values of RSSI are produced at different conditions. Thus it is so much troublesome to get the actual position of sensor nodes using RSSI. In our experiments, we tried to investigate the reasons of deviation in RSSI values in different conditions using TelosB sensor nodes. We showed the effects of different obstacles between the sensor nodes and their different orientations as well. The results show that, the distances, obstacles and sensor node orientations play a significant role in changing the RSSI values.