esources. The QPSK-modulated symbols are then mapped to subcarriers across multiple resource blocks using one or two OFDM symbols. A pseudo-random QPSK sequence, mapped to every third subcarrier on each OFDM symbol, is used as a DM-RS to facilitate coherent detection at the base station [14]. The physical layer processing of UCI starts with CRC attachment and channel coding (see Fig. 4.80). Let us a1, aNuci-1 denote the input UCI bit sequence, in which NUCI is the payload size. If NUCI 12 the UCI bits are encoded with the polar codes and if NUCI VI 11, Reed-Muller codes, simplex code (NUCI = 2), or repetition coding (NUCI = 1) would be used to encode the UCI bits [7]. If the payload size NUCI 12, code block segmentation and CRC attachment may be performed prior to channel coding. If NUCI 360, E > 1088 bits or if NUCI > 1013, = 1 segmentation is performed; otherwise, Iseg = 0 and no segmentation is done, where E is the rate-matched output sequence length. If 12 VI NUCI < 19, the parity bits Pro,Pr1 Pr(NcRc-1) are computed by setting NCRC = 6 bits using the generator polynomial gCRC6(D). The resulting sequence is C10, C11, C1(K1-1) where l is the code block number and K is the number of bits associated with the 1th code block. If NUCI > 20, the parity bits are computed by setting NCRC = 11 bits using the generator polynomial gCRC11(D) [7]. Note that if the payload size NUCI < 11, no CRC bits are attached. The information bits are later encoded by channel coding block. The total number of code blocks is denoted by C and each code block is individually encoded. If 18 < K1 < 25, the information bits are encoded with polar encoder by setting the parameters as follows: nmax = 10, I = 0, NPC = 3, NPC = 1, if E - K1 + 3 > 192; otherwise, nwm=0, in which E1 is the rate-matched output sequence length of the 1th code block. If K1>30, the Reed-Muller codes are a family of linear error-correcting codes used in communication systems. The special cases of Reed-Muller codes include Hadamard codes, Walsh-Hadamard codes, and Reed-S