On the capacity of HetNets

Heterogeneous wireless networks provide a means to increase network capacity by introducing small cells and adopting a layered architecture. These networks allocate resources flexibly through a combination of time sharing and cell range expansion/contraction allowing a wide range of possible schedulers. In this paper we define capacity of such networks in terms of the maximum number of downloads per second which can be achieved for a given offered traffic density. In a simplified model we show that this capacity is determined via the solution to a continuous linear program (LP). If the solution is smaller than 1 then we show that there is a scheduler such that the number of mobiles in the network has ergodic properties with finite limiting moments. On the other hand if the solution is greater than 1 then we show that no such scheduler exists.