Transmit Power Control in MIMO Cellular Systems

It is well known that the implementation of multiple-input multiple-output (MIMO) systems in a cellular environment is hampered by the effects of inter-cell interference. In this paper we look at controlling the base station power to increase overall system capacity. We define the optimization problem and show that the sub-optimal solution, where each base station either transmits at maximum power or is switched off, is optimal in the majority of cases. We then develop a simple and practical algorithm to find a near optimal solution. Our results show that simple power control can increase system capacity significantly, especially at high transmit power levels, and with massively reduced complexity with respect to the optimal solution