For each UE, a base station determines the number of streams for transmitting a data signal, performs different precoding on the data signal depending on the UE, and allocates different transmission powers to at least two UEs. The base station transmits streams addressed to the at least two UEs in a form in which these streams are non-orthogonally mixed, with transmission powers that are different for the UEs. For each of the streams addressed to these UEs, the base station estimates predictive indices for these UEs from channel state information determined by the UEs to which those streams are addressed, and, based on the predictive indices, allocates different transmission powers to those UEs such that the better the predictive index is, the lower the transmission power is.