Patent attributes
Systems, methods, and instrumentalities are described herein for supporting CBG-based retransmission with variable CBG size using variable length HARQ-ACK. A WTRU may receive a configuration to use a first table. The first table may be associated with a maximum number of code block groups per transport block (maxCBG/TB). The WTRU may determine a number of HARQ-ACK bits to send for code blocks. The determination may depend on whether an indication is received to switch from the first table to a second table. On a condition that the indication to switch from the first table to the second table is received, the WTRU may send a number of HARQ-ACK bits that is equal to two times the maxCBG/TB. The WTRU may receive a retransmission of a number of code blocks, wherein a code block group size depends on a sent number of HARQ-ACK bits.