Pre-talk listen procedure in wireless devices and wireless networks

摘要

A wireless device receives an uplink grant for a licensed assisted access (LAA) cell. The uplink grant comprises a physical uplink shared channel (PUSCH) starting position field and a listen-before-talk (LBT) type field. The PUSCH starting position field indicates a PUSCH starting position in a subframe of the LAA cell. The LBT type field indicates at least one of a first LBT type or a second LBT type for the subframe. A determination is made based, at least, on uplink transmissions by the wireless device in a preceding adjacent subframe of the LAA cell, to: perform an LBT procedure for transmission of uplink signals in the subframe, or transmit the uplink signals without performing the LBT procedure for the subframe, regardless of the LBT type field indicating the first LBT type or the second LBT type. The uplink signals in the subframe may be transmitted via the LAA cell.