A wireless device receives a sounding reference signal (SRS) request field and an ending symbol field for a physical uplink shared channel (PUSCH). The SRS request field indicates an SRS is not transmitted in a last symbol of a subframe of an unlicensed cell. The ending symbol field indicates the PUSCH is not transmitted in the last symbol for a first listen before talk procedure to be performed during the last symbol. A packet is transmitted in the subframe via the PUSCH based on the ending symbol field.