SIMULATION AND ANALYSIS OF RSSI BASED TRILATERATION ALGORITHM FOR LOCALIZATION IN CONTIKI-OS

The recent progress in Wireless sensor networks is contributed by improvisation in research activities in the domain of embedded system and radio communication. Localization is one of the most important challenge in WSNs, in view of the fact that it plays a significant part in many applications, e.g., explore, catastrophe assistance, rescue operations, tracking the target and multiple tasks in smart milieus. Localization of node involves the activity of monitoring events, group discussion between the nearby sensors, routing the necessary information to the destination by keeping network coverage in check. In this research paper, Received Signal Strength Indicator (RSSI) based trilateration algorithm is proposed for localizing a blind node present in the network with minimal localization error. The position coordinates of the blind node is estimated based on the distance estimates and corresponding position coordinates of the anchor nodes present in the network. This work was performed in Contiki-OS with the help of built-in simulator COOJA. Based on the simulation results conducted with random position coordinates, the obtained localization error is found to be approximately 1.9 meters. The obtained error margin though not stringently accurate, but is acceptable, considering the environment in which the nodes are deployed which experiences varying channel characteristics, multipath fading and shadowing.