Power Allocation for Decode-and-Forward Cellular Relay Network With Channel Uncertainty

In this paper, the authors propose centralized and distributed power allocation algorithms for a multi-user, multi relay cellular network using Decode-and-Forward (DF) cooperation strategy taking channel uncertainty into account. The objective is to minimize the total uplink power of the network taking each user's target data rate as the Quality of Service (QoS) constraint under imperfect Channel State Information (CSI). They consider the worst-case optimization approach, in which QoS constraint is satisfied for all channels contained in some uncertainty region.