SYSTEMS AND METHODS FOR PHYSICAL UPLINK SHARED CHANNEL (PUSCH) FORMAT SIGNALING AND CONTENTION ACCESS
A user equipment (UE) for transmitting signals in a Licensed-Assisted Access (LAA) serving cell is described. The UE includes a processor and memory in electronic communication with the processor. The UE receives an uplink (UL) grant for one or more UL LAA subframes from one or more downlink control information (DCI). The UE also determines a UL LAA physical uplink shared channel (PUSCH) format or structure for a UL LAA subframe. The UE further determines whether listen before talk (LBT) is needed for a scheduled LAA PUSCH. If needed, the UE determines a UL contention access region based on the UL grant for a UL LAA subframe. The UE also determines a UL contention access method in the contention access region. The UE further performs UL contention access in the UL contention access region. The UE additionally transmits the LAA PUSCH if channel access succeeds.
1 . A user equipment (UE) for transmitting signals in a Licensed-Assisted Access (LAA) serving cell, comprising:
a processor; and
memory in electronic communication with the processor, wherein instructions stored in the memory are executable to:
receive an uplink (UL) grant for one or more UL LAA subframes from one or more downlink control information (DCI);
determine a UL LAA physical uplink shared channel (PUSCH) format or structure for a UL LAA subframe; and
determine whether listen before talk (LBT) is needed for a scheduled LAA PUSCH; and if needed
determine a UL contention access region based on the UL grant for a UL LAA subframe;
determine a UL contention access method in the contention access region;
perform UL contention access in the UL contention access region; and
transmit the LAA PUSCH if channel access succeeds.
2 . The UE of claim 1 , wherein the UL grant DCI indicates the LAA PUSCH format of the scheduled subframe and information about the availability of the last symbol of the previous subframe.
3 . The UE of claim 1 , wherein the UL LAA PUSCH format or structure for a UL LAA subframe may start from symbol 0 or 1 and may end at symbol 12 or symbol 13 .
4 . The UE of claim 1 , wherein the UL LAA PUSCH starts at symbol 0 , and the last symbol of a previous subframe is not blank, and when a previous LAA subframe transmission is successful, the UE transmits the scheduled LAA PUSCH without LBT.
5 . The UE of claim 1 , wherein the contention access region is determined based on an indicated LAA PUSCH structure.
6 . The UE of claim 1 , wherein the contention access region is determined based on an indicated LAA PUSCH structure and whether the last symbol of a previous subframe is blank.
7 . A method for transmitting signals in a Licensed-Assisted Access (LAA) serving cell, comprising:
receiving an uplink (UL) grant for one or more UL LAA subframes from one or more downlink control information (DCI);
determining a UL LAA physical uplink shared channel (PUSCH) format or structure for a UL LAA subframe; and
determining whether listen before talk (LBT) is needed for a scheduled LAA PUSCH; and if needed
determining a UL contention access region based on the UL grant for a UL LAA subframe;
determining a UL contention access method in the contention access region;
performing UL contention access in the UL contention access region; and
transmitting the LAA PUSCH if channel access succeeds.
8 . The method of claim 7 , wherein the UL grant DCI indicates the LAA PUSCH format of the scheduled subframe and information about the availability of the last symbol of the previous subframe.
9 . The method of claim 7 , wherein the UL LAA PUSCH format or structure for a UL LAA subframe may start from symbol 0 or 1 and may end at symbol 12 or symbol 13 .
10 . The method of claim 7 , wherein the UL LAA PUSCH starts at symbol 0 , and the last symbol of a previous subframe is not blank, and when a previous LAA subframe transmission is successful, the UE transmits the scheduled LAA PUSCH without LBT.
11 . The method of claim 7 , wherein the contention access region is determined based on an indicated LAA PUSCH structure.
12 . The method of claim 7 , wherein the contention access region is determined based on an indicated LAA PUSCH structure and whether the last symbol of a previous subframe is blank.