Localization of WSN Nodes Based on NLOS Identification Using AOAs Statistical Information

Localization is one of the major issues in the field of wireless sensor networks (WSN). In the non-line of sight (NLOS) environments because of the obstacles between the anchor nodes and other nodes, a signal which is used to determine the distance between nodes cannot pass through a straight path. This problem increases localization error. In this paper we present a new localization method based AOA measurement for the NLOS environments. The main idea of the proposed method is the identification of NLOS nodes and then eliminating them from the localization process. Identification of the NLOS nodes is based on the statistical model of the measurement error and NLOS error where we apply the NP theorem to determine a threshold value to the AOA in order to identify the NLOS nodes. The simulation results of proposed method show that it has good performance in localization in the NLOS conditions.