When does the AP deployment incentivize a user to offload cellular data: An energy efficiency viewpoint

In this paper, we consider a cellular network supplemented with some WiFi access points (APs) for mobile data offloading. In the network, a mobile user can transmit its data directly to the base station or attempt to use WiFi networks to offload some data traffic from the cellular network. From an energy efficiency viewpoint, we derive the condition of incentivizing a user to use the WiFi networks in a general framework. Using our results, AP deployment problems of minimum deployment and maximum coverage are reconsidered, and we propose algorithms to solve the problems. In addition, we discover an interesting property of the problems that the optimal deployment in a target region, which is divided into grids with AP coverage, can be achieved when at most one grid is covered by more than one AP.