Hop-count based localization using geometric constraints in wireless sensor networks

Localization is an important issue in wireless sensor networks because many applications provide services with location information of the events in sensing areas. Among conventional localization schemes, hop-count based localization schemes are very promising with respect to the cost because the location estimate can be achieved using connectivity information without a special module for localization. However, hop-count based schemes have a weakness that the location estimate is coarser than localization schemes using measured distance or angle information. To improve the localization accuracy encountered in estimating the location from the coarse distance estimate, this paper proposes a localization scheme that utilizes geometric constraints to narrow down a potential area where a sensor node is supposed to be, and then estimates its location. Through simulation results, the proposed scheme is shown to provide higher localization accuracy and lower power consumption in comparison to the existing hop-count based schemes.