Time variant power control in cellular networks

Abstract

We study the transmission power control in a cellular network where users mobility results in a time varying gain matrix. A framework for evaluating the channel quality is specifled, and an asymptotic representation of the link gain evolution in time is obtained. Then, a variant of a standard Distributed Constrained Power Control (DCPC) which copes with user mobility is derived. These two power controls, as well as constant-received power and constant-transmitted power controls are compared with respect to their outage probabilities in a Manhattan-like microcellular system. The comparison reveals that the classical DCPC algorithm has an outage probability close to one, unless some counter-measures are taken. The time variant algorithm however, copes well with users mobility and provides a close to an optimal scale up factor for the Signal to Interference Ratio (SIR) target. Furthermore, the time variant algorithm provides a substantial reduction in outage probability compared to the other algorithms above.