Base stations and methods

A base station which communicates with a user equipment (UE), the base station comprising:

• higher layer processing circuitry configured to send radio resource control (RRC) configuration information, the RRC configuration information indicating code block group (CBG) transmission for a Physical Downlink Shared Channel (PDSCH);
• transmitting circuitry configured to, after a channel access procedure, retransmit, to the UE, a PDSCH containing a transport block with a first CBG but without a second CBG;
• and
• receiving circuitry configured to receive, from the UE, a HARQ-ACK feedback including a first HARQ-ACK information bit and a second HARQ-ACK information bit for the transport block of the PDSCH, the first HARQ-ACK information bit corresponding to the first CBG, and the second HARQ-ACK information bit corresponding to the second CBG;
• wherein
• the second HARQ-ACK information bit is set to ACK, and
• a contention window for the channel access procedure is adjusted using the HARQ-ACK feedback, wherein the second HARQ-ACK information bit is ignored.

A method for a base station which communicates with a user equipment (UE), the method comprising:

• sending first radio resource control (RRC) configuration information, the first RRC configuration information indicating code block group (CBG) transmission for a Physical Downlink Shared Channel (PDSCH);
• sending second RRC configuration information, the second RRC configuration information indicating Nmax which is a maximum CBGs per transport block;
• after a channel access procedure, transmitting, to the UE, a PDSCH containing a transport block with N CBG(s), N being an integer;
• and
• receiving, from the UE, a HARQ-ACK feedback including Nmax HARQ-ACK information bits for the transport block of the PDSCH;
• wherein
• if N is smaller than Nmax, the HARQ-ACK information bit(s) for last Nmax-N CBG(s) are set to NACK, and
• a contention window for the channel access procedure is adjusted using the HARQ-ACK feedback, wherein the HARQ-ACK information bit(s) for last Nmax-N CBG(s) are ignored.

A method for a base station which communicates with a user equipment (UE), the method comprising:

• sending radio resource control (RRC) configuration information, the RRC configuration information indicating code block group (CBG) transmission for a Physical Downlink Shared Channel (PDSCH);
• after a channel access procedure, retransmitting, to the UE, a PDSCH containing a transport block with a first CBG but without a second CBG;
• and
• receiving, from the UE, a HARQ-ACK feedback including a first HARQ-ACK information bit and a second HARQ-ACK information bit for the transport block of the PDSCH, the first HARQ-ACK information bit corresponding to the first CBG, and the second HARQ-ACK information bit corresponding to the second CBG;
• wherein
• the second HARQ-ACK information bit is set to ACK, and a contention window for the channel access procedure is adjusted using the HARQ-ACK feedback, wherein the second HARQ-ACK information bit is ignored.