5G-NR Uplink HARQ decision

5G NR
,
1

Hey Folks

In NR for uplink HARQ only decided on basis of DCI NDI bit toggled.

So, having this, let suppose UE have only 10 packets (1 TTI / PACKET) to send in UL for every packet UE will get new DCI which carry resources for another packet and says NDI bit for ack / nack now it will continue for 9th packet after sending 10th packet UE will not get any DCI since UE doesn’t have anything to send in UL so for 10th packet how UE will get the Ack/Nack.

My opinion is: For every last packet UE will not receive any Ack/Nack.

Is this correct or any another concepts behind this?

2

UE never received ACK/NACk. It concludes from the next DCI with the same HARQ id that CRC passed or failed for previous PUSCH sent and
If failed/DTX, gnB schedule
{
New DCI from reTX leg //NACK
}
Else
{
No action // UE assume this as ACK
}

1 Like
3

So for this DCI eNodeB will assign new resource allocation or UE can use same resource for retransmission?

4

It’s totally on implementation at gNB side.

Most of the time same resources.