Range Free Localization in Anisotropic Networks using Unbiased Distance Model

In this paper, the authors propose a novel range-free localization method to localize the sensor nodes in anisotropic networks. The basic methods of range-free localization assume the hop-size of all links to be the same. This assumption is valid only in scenarios where the node distribution is fairly balanced. This is not practically accurate due to the random deployment of nodes in wireless sensor networks. Hence, the method of finding hop-size using the expected distance and hop-count between the sensor nodes is used in our work. This method is applied to anisotropic networks where obstacles are present. Extensive simulation studies have been conducted to validate the accuracy of the proposed method under the effects of log-normal shadowing which is practically relevant. The results are compared with DV-Hop and Reliable anchor pair selection method (RAPS). This method gives up to 35% performance improvement over DV-Hop technique and 15% performance improvement over RAPS technique in the literature.