Localization Technique for Lost Node in Geo-location

The use of location based authentication services has seen a sudden boom with the reduced cost of GPS hardware and small size-factors. However, the drawbacks associated with the GPS related services makes it infeasible to incorporate GPS in all the mobile nodes (MN) and subject to availability of GPS signals. This demands for alternatives that can be used directly or indirectly in place of GPS for geo-localization of a lost node or a mobile node with no GPS capability. A number of such techniques has been proposed for non-GPS dependent localization of wireless nodes. Some of these can be used directly or indirectly for geo-localizing lost nodes. We present a comparative study of these techniques on the basis of several metrics such as complexity, additional hardware requirement, efficiency, operative field etc.