Base station arrangement (100) adapted to receive signals from a user station; adapted to be connected to or comprises a plurality of antenna elements (1, 1, 2, 2, . . . 4,) with antenna ports (11, . . . 11) and a signal processing unit (20). The base station (21) also comprises a signal pre-processing functional unit (30) to collect channel correlation information. It is adapted to establish if there is one or more distinguishing characteristics comprising different correlation properties of different configuration properties associated with the antenna elements. Antenna elements are then assigned to different groups based on said configuration properties, and the channel correlation information is used to generate weighting information which is applied to antenna ports connected to antenna elements to control the antenna ports connected to antenna elements to control the antenna element transmit power individually or groupwise.