Range-Free Localization Algorithm for IEEE802.11 WLAN Based on K-NN

Nowadays, localization of mobile node using wireless local area network (WLAN) become a most emerging area. Its location based services leads to make it applicable in various fields like intruder identification, healthcare system, navigation etc. To determine the location of a mobile node various localization techniques have been proposed. In this paper, we propose a new range-free localization algorithm based on K-nearest neighbors (K-NN) method for IEEE802.11 WLAN. Our algorithm finds K-NN by comparing received signal strength (RSS) of mobile node (MN). Thereafter, location of MN is computed by calculating weighted average of coordinates of K-NN. We also compared our proposed algorithm with RSS difference and conventional K-NN methods. Extensive simulation results show that the accuracy of our algorithm is better than these two methods. We also examine the effect of network size, grid size, number of access point (AP) and shadowing factor on localization accuracy of proposed algorithm.