Devices and methods for elaa multi-carrier lbt

A computer-readable storage medium comprising instructions for license-assisted access (LAA) uplink communication operations that, when executed by processing circuitry of an apparatus, configure the apparatus to:

• process one or more uplink (UL) grants from an evolved node B (eNB) scheduling a plurality of physical uplink shared channel (PUSCH) transmissions on a plurality of unlicensed carriers at a first PUSCH starting position, the one or more UL grants indicating a first channel access procedure for the plurality of PUSCH transmissions;
• autonomously select a first unlicensed carrier of the plurality of unlicensed carriers for the first channel access procedure associated with the first PUSCH starting position;
• and
• select remaining unlicensed carriers of the plurality of unlicensed carriers other than the first unlicensed carrier for a second channel access procedure associated with the first PUSCH starting position.

An apparatus of a user equipment (UE) configured to operate using a plurality of unlicensed carriers in a license-assisted access (LAA) system, the apparatus comprising:

• a communication interface configured to receive one or more channel access indications from one or more uplink (UL) grants from an evolved node B (eNB) scheduling a plurality of physical uplink shared channel (PUSCH) transmissions on the plurality of unlicensed carriers at a first PUSCH starting position;
• and
• processing circuitry coupled to the communication interface and configured to:
• process the one or more UL grants to identify the first PUSCH starting position for the plurality of PUSCH transmissions on the plurality of unlicensed carriers;
• process the one or more UL grants to identify a Type 1 channel access procedure for the plurality of PUSCH transmissions on the plurality of unlicensed carriers;
• select a first carrier of the plurality of unlicensed carriers;
• initiate the Type 1 channel access procedure on the first carrier in response to selection of the first carrier;
• initiate a first PUSCH transmission of the plurality of PUSCH transmissions on the first carrier of the plurality of unlicensed carriers in response to the Type 1 channel access procedure;
• and
• initiate Type 2 channel access procedures on one or more second carriers of the plurality of unlicensed carriers, wherein the one or more second carriers do not include the first carrier, and wherein the Type 2 channel access procedures are performed immediately before the first PUSCH transmission on the first carrier.