Downlink transmission with two-stage feedback:early prediction-based feedback of Physical Downlink Shared Channel and Hybrid Automatic Repeat Request feedback

摘要

Downlink transmission from base station, gNB, to user equipment, UE, comprising, at the base station: transmitting data 120 to the UE; receiving 140 an early prediction feedback signal from the UE. Based on the early prediction feedback, if it indicates discontinuous transmission, DTX, 152, retransmitting the data to the user equipment. If it indicates negative acknowledgement, NACK, 154, determining, whether a sufficient latency budget is available to wait for a normal HARQ ACK/NACK 164. If the budget is available normal HARQ feedback is awaited 166. If sufficient budget is not available, retransmitting the data 120 to the user equipment. The method further comprises receiving HARQ feedback 166 and, if the HARQ feedback indicates NACK, 178, retransmitting the data to the user equipment and repeating the method. The method may comprise, for the UE: receiving data from the base station; estimating an error probability based on a portion of the received data based on log likelihood ratios; generating and sending to the base station a signal indicative of early feedback based on the estimated error probability. Estimating the error probability may be further based on a signal received earlier as decoded downlink control information, DCI. Embodied is a URLLC 5G channel.