RSSI based Node Localization using Trilateration in Wireless Sensor Network

Abstract

Wireless Sensor Network (WSN) is an ad-hoc network generally used to perform various monitoring tasks deployed randomly in different environments. There are various applications of WSN which require the knowledge of the location of sensor node makes the sensing data more significant. This aspect of information increases the diversity of applications. In most of the Wireless Sensor Networks where nodes are deployed randomly, estimating the location of these nodes is a difficult task. Trilateration is one of the common localization methods. In this method usually Received Signal Strength (RSS) is used to estimate the nodes distances. Although this method is a very simple technique but create significant error in localization estimations. This paper proposes a method to minimize the error in location estimations. The experiments have been done on wireless IRIS motes testbeds. The procedure has been applied in both indoor and outdoor environment using RSS ranging method, considering the nodes in Line of Sight (LOS). Results have shown that the distance estimation error in indoor was 83.32% which reduced to 3.21% for indoor and from 82.6% to 4.14% for outdoor. The minimum node localization error was 0.126 meter in indoor and 0.218 meter in outdoor.