Novel range-free immune to radio range difference (IRRD) geo-localization algorithm in wireless networks

This paper presents a novel range-free immune to radio range difference (IRRD) geo-localization algorithm in wireless networks. The algorithm does not require the traditional assumption of anchor (location aware) nodes that have the same communication range as it works with anchor nodes having homogeneous and/or heterogeneous communication ranges. It is rang-free - it utilizes node connectivity to estimate the position of unknown (location unaware) nodes using two or more anchor nodes. The algorithm works in two steps: in the first step, the True Intersection Points (TIPs) forming the vertices of the smallest communication overlap polygon (SCOP) of the anchor nodes are found. In the second step, it estimates the position of the unknown node at the center of the SCOP which is formed from these TIPs. The problem is first geometrically and mathematically modeled, then new localization approach that does not assume anchor nodes have the same radio range is proposed.