A wireless device receives configuration parameters indicating a bandwidth part (BWP), of a cell, associated with a maximum number of transmission layers and a plurality of demodulation reference signal (DMRS) ports. The wireless device receives a downlink control information comprising an antenna port indication value. A subset of DMRS ports, from the plurality of DMRS ports, is determined based on the maximum number of transmission layers associated with the BWP. A transport block is received via the BWP with one or more DMRS ports selected, based on the antenna port indication value, from the subset of DMRS ports.