f- frame timing. It then attempts to find the SSS in order to detect the cyclic prefix length as well as the duplexing scheme and to obtain the exact frame timing based on matched filter results for the PSS and SSS. It then proceeds to detect the cell identity from the reference signals sequence index and to decode the PBCH for the purpose of obtaining the minimum SI. The synchronization signal (SS) blocks are organized into SS bursts and SS bursts are organized into SS burst sets that are periodically transmitted in order to support beamform- ing operation. In NR, there are 1008 unique physical-layer cell identities, that is, an increased number compared to 504 in LTE in order to provide sufficient deployment flexibility in dense net- work topologies. As shown in Fig. 4.27, the NR physical-layer cell identities are in 336 unique physical-layer cell-identity groups, each group containing three unique identities. Each NR cell ID can be jointly represented by a PSS/SSS combination. The PSS consists of three frequency-domain binary BPSK length-127 M-sequences, and the SSS corresponds to 336 Gold sequences with length-127. Both of these signals are mapped into 127 contiguous subcarriers. A physical-layer cell identity is uniquely defined by a number in the range of 0-335, representing the physical-layer cell-identity group, and a number in the range of 0-2, representing the physical-layer identity within the physical-layer cell-identity group as Maximum length sequences are pseudo-random binary sequences that are generated using maximal linear feedback shift registers. The M-sequences are periodic and reproduce every binary sequence that can be reproduced by the shift registers (i.e., for length-m registers, they produce a sequence of length 2m - 1). An M-sequence is spectrally flat with the exception of a near-zero DC term. Since M-sequences are periodic and shift registers cycle through every possible binary value with the exception of the zero vectors, the registers can be initialized to any state with the excepti