Optimal inter-cell coordination for elastic data tracffic

Abstract

In cellular networks, where the wireless access is fairly shared among users, individual data rates are subject to variation because of the random nature of the number of active flows in a cell. Another factor is the radio channel quality, which depends highly on the users' positions in the cell, and on the interference caused by nearby base stations.

While user activity is random, its effects can be compensated by inter-cell interference coordination. This thesis proposes a queuing model of two interfering base stations, and considers the possibility of turning them on and off depending on the number of users in each cell.

We then devise an optimal time scheduling policy that is a set of rules that minimizes the average total number of users in the system and therefore the average delay.

We establish that depending on the level of interference, it is beneficial to either serve always both cells at the same time, or on the contrary, to always serve only one queue at a time.