Localization in Wireless Sensor Networks Based onFuzzy Logic

ABSTRACT: One of the fundamental problems in Wireless Sensor Networks (WSNs) is the localization of sensor nodes based on the known location of several nodes. In this thesis one of the intelligent localization schemes, which is a range free localization is used to estimate the location of the unknown nodes. In the proposed method, the anchor nodes (reference nodes) are connected to the sensor nodes and then each sensor node receives the signal strength indicator (RSSI) from each of the anchor nodes. The RSSIs are achieved based on the distance of the sensor node to each of anchor nodes. The RSSIs are fed to the sugeno fuzzy inference system to calculate the weights used in the centroid relation. The centroid technique is the range free based localization scheme, which is proposed to estimate the location of the sensor nodes. Both analytical and experimental approaches are considered where the analytical approach is done by sugeno fuzzy inference in the two different environments with and without Additive White Gaussian Noise (AWGN). The experimental method is done for 6 sensor nodes and repeated 6 times in different positions in a region. There is an error of locating the actual and the estimated nodes in both analytical and experimental approaches. The error of location of the estimated sensor nodes in the experimental method is not much in comparison with the analytical method. Keywords: Range free localization, received signal strength indicator, centroid localization, fuzzy logic system and wireless sensor network. ……………………………………………………………………………………………………………………………………………………………………………………………………………………