Fast Power and Channel Adaptation for Mobile Users in OFDMA Multi-Cell Scenarios

Methods for interference mitigation and adaptive multi-user resource allocation are among the most promising technological breakthroughs that should improve capacity of the last generation broadband wireless systems. In multi-cell scenarios characterized by radio technologies based on OFDMA (Orthogonal Frequency Division Multiple Access), co-channel interference is the performance limiting factor and techniques that reduce the transmission power act indirectly on the co-channel interference levels. In this paper we investigate multi-cell systems in which power and channel adaptation act as a positive factor on the interference reduction. We are interested particularly in the role of the closed loop power control and of simple techniques for fast channel assignment in multi-cell scenario with low reuse factors (possibly close to 1). It is found that, in multi-cell scenarios, spectral efficiency and possibly coverage can be improved by algorithms that are simple and fast enough to be exploited for mobile users.