A Dynamic HARQ Feedback Method in NR Communication Systems

In NR (New Radio), Hybrid automatic repeat request (HARQ) feedback type is statically configured as either transport block based feedback or code block group based feedback when the serving cell is established. This paper proposes a method to dynamically indicated the HARQ feedback type based on the channel state. To achieve this, the paper suggests adding a HARQ feedback type indicator field to the downlink DCI. The HARQ feedback type indicator instructs the HARQ feedback type for the transmitted DL data. The HARQ feedback type can be changed based on the channel state for each HARQ codebook period. By dynamically indicating the HARQ feedback type, efficient utilization of PUCCH resources for the HARQ codebook transmission and PDSCH resources for retransmissions can be achieved.