Study of Localisation Methods of Mobile Users in Wireless Sensor Networks

To track the exact position of a mobile user is an important role for location services in an indoor environment. Low power, low cost and low complexity are the important characteristics of wireless sensor network. Indoor position system performance can be enhanced drastically with these properties. Diffraction, scattering and reflection has adverse effect on radio signal propagation, therefore the received signal strength requires good calibration method to provide accurate position. In this paper, grey prediction method is used in wireless sensor network and it makes use of wireless techniques (Zigbee/802.15.4). Received Signal Strength Indicator (RSSI) is predicted using the grey prediction, and Dynamic triangular (DTN) location method is also designed. For performance analysis, mean distant error of RSSI at offline stage on mobile user can be within 2.3m.In run time stage, grey prediction give more accurate predicted position and carries out mean distance error within 1.3 m.