8.3A Autonomous uplink feedback procedure

36.2133GPPEvolved Universal Terrestrial Radio Access (E-UTRA)Physical layer proceduresRelease 17TS

If the UE detects on the scheduling cell for an UL transmissions on an LAA SCell a transmission of DCI Format 0A/4A with the CRC scrambled by AUL C-RNTI carrying AUL-DFI, the UE shall use the autonomous uplink feedback information according to the following procedures:

– For each HARQ process configured for autonomous uplink transmission, the corresponding HARQ-ACK feedback is delivered to higher layers. For the HARQ processes not configured for autonomous uplink transmission, the corresponding HARQ-ACK feedback is not delivered to higher layers;

– For an uplink transmission in subframe n, the UE expects HARQ-ACK feedback in the AUL-DFI at earliest in subframe n+4;

– If the UE receives AUL-DFI in a subframe indicating ACK for a HARQ process, the UE is not expected to receive AUL-DFI indicating ACK for the same HARQ process prior to 4ms after the UE transmits another uplink transmission associated with that HARQ process;

– The "TPC for PUSCH’ information is applied according to the procedures in clause 5.1;

– If present, the UE applies the TPMI field received in subframe n for autonomous uplink transmissions starting from subframe n+4. The UE is not expected to receive a TPMI that changes the number of transmission layers.