Energy-Efficient Localization Strategy For Smartphones

In recent years, smartphones have become prevalent. Lots of applications have been developed, which is convenient for humans. Examples of such applications are target tracking and mobile search. However, these applications are so frequently used that the phone battery is drained quickly and the battery lifetime is reduced. To overcome the problem, we present an energy-efficient localization strategy for the location-based services of smartphones.It is known for us, GPS is a very popular localization technique because of its high accuracy. However, GPS is energy-hungry. It is obvious that GPS should be avoided to use. The proposed strategy for single object selects the energy-optimal one from multiple localization techniques at the localization time point. Also, it dynamically estimates the next localization time point to avoid unnecessary localization operations after obtaining application accuracy requirement. The localization time point is when the estimated position of user does not meet the application accuracy requirement. In addition, we present an energy-efficient strategy for multiple objects. The strategy improves the above strategy by utilizing the cooperation operations among multiple objects. In the cooperative process, each user sends one message to each other and their resources are shared by themselves. These resources are useful for some users whose position accuracies are low. Improving the position accuracies of the part of users will prolong the time interval of two consecutive localization operations. Further, this reduces energy consumption of smartphones.We evaluate the non-cooperative localization strategy for single object and the cooperative localization strategy for multiple objects through a series of simulations. Experimental results show that the two strategies can significantly reduce the localization energy consumption of smartphones while ensuring a good satisfaction degree.