A wireless device receives messages indicating CSI measurement resources of cells belonging to at least two base stations or belonging to at least two sectors of a base station. The wireless device measures CSI employing at least CSI measurement resources of the cells. The wireless device quantizes the measured CSI jointly across cells and encodes and transmits the jointly quantized CSI. The wireless device receives a resource assignment for data packet(s). The wireless device receives signals carrying the data packets from multiple cells.