Uplink transmissions via a license assisted cell in a wireless network

A wireless device comprising:

• one or more processors;
• and
• memory storing instructions that, when executed by the one or more processors, cause the wireless device to:
• receive a downlink control information comprising:
• an allocation of resource blocks for transmission of uplink data via a subframe of a licensed assisted access (LAA) cell;
• a first field comprising an index indicating a starting position for the transmission of the uplink data, the index identifying one of pre-configured starting positions;
• and
• a second field indicating an ending symbol for the transmission of the uplink data, the ending symbol being one of pre-configured ending symbols;
• perform, before the starting position of the subframe, a listen-before-talk procedure indicating a clear channel;
• map, based at least on the starting position and the ending symbol, the uplink data to resource elements corresponding to the resource blocks;
• and
• transmit, the uplink data via the LAA cell, starting at the starting position in the subframe and ending before the ending symbol.