5G NR uses low density parity check (LDPC) codes for the data transmission for mobile broadband (MBB) services and polar codes for the control signaling.
LDPC codes are attractive from an implementation perspective, especially at multi-gigabits-per-second data rates. The LDPC codes considered for NR use a rate-compatible structure unlike the LDPC codes used in other wireless technologies. This permits the transmission at different code rates and for HARQ operation.
NR employs Polar Codes for the physical layer control signaling where the information blocks are relatively small compared to data transmission.
By concatenating the polar code with an outer code and by performing successive cancellation list decoding, good performance is achieved at shorter block lengths. Reed-Muller codes are used for the smallest control payloads.