Patent attributes
Channel clearance using a shared radio frequency spectrum band may be performed for both a base station and a user equipment (UE). A base station may perform a listen before talk (LBT) procedure and verify one or more channels in a shared radio frequency spectrum band are available for transmissions and, if the LBT procedure is successful, transmit a pre-grant transmission to one or more UEs. The UEs may perform an LBT procedure for channel(s) indicated in the pre-grant transmission. If the UE LBT procedure passes, the UE may transmit a channel clearance signal, and may transmit a feedback communication responsive to the pre-grant transmission. The feedback communication may indicate, for example, the pre-grant transmission was received and which of the one or more channels are available based on the LBT procedure. The base station may receive the feedback communication and initiate transmissions to the UE.