What is the use of NDI bit in HARQ context? If it says new data indicator then why do we need it because ACK or NACK is enough to decide next transmission is new Tx or re-Tx.
Hi,
NDI bit describes whether the received TB is new transmission or re-transmission. If previous NDI and current NDI for the same HARQ process is same then it is re- transmission otherwise new transmission.
UE used NDI bit to decide the transmission is new or re transmission .When UE ignores this bit and continue.
This is non adaptive transmission , But if we receive ack then why do we need non adaptive transmission?
