A large scale cooperative localization method

Smart phones and Location Based Services (LBSs) are getting very popular in recent years. To this end, locating the positions of smart phones becomes inevitable. To date, there exist some localization systems in some specific areas. For instance, GPS can be used only in the outdoor space. However, people always live in large scale environments like campus, urban and tourist areas, including both indoor and outdoor space. For large scale environment, a single location technique is not always available everywhere. Therefore, we propose a heterogeneous localization algorithm which combines GPS, WiFi and Internet Of Things (IOT) localizations. We also introduce the "localization possibility" for each localization method to estimate the most "reliable" (possible) one. Besides, the more reliable nearby users provide their localization information, the further enhancement of the localization accuracy will get. By measuring the relative WiFi signal strength, it helps especially those users who have no any available localization methods. We call this concept "cooperative localization". Finally, we evaluate the accuracy of our algorithms by simulation. Because signal strength fluctuates from minute to minute, we measure empirical data and put into the simulator to do our experiments. Finally, we also verify that our idea can be implemented on smart phones and work feasibly.