Random Access Preamble Sequence Design in High-Speed Scenario

Random access preamble sequences are sent from the user equipment (UE) to gNodeB though Physical Random Access Channel to access to the network. In high-speed scenarios, the performance of random access based on Zadoff-Chu sequences degrades due to the Doppler frequency offset which breaks the sub-carrier orthogonality. In this paper, a random access preamble sequence with linear change in phase is proposed based on the analysis of the influence of frequency offset on the correlation results of random access preamble sequence. The method of decreasing the peak-to-average power ratio of time domain sequence and the random access preamble sequence design compatible with orthogonal time-frequency space technology are proposed. The false detection rate and the timing error distribution are evaluated. The simulation results show that the proposed designs of random access preamble sequence are insensitive to frequency offset, and the detection performance and timing performance are almost unaffected by frequency offset.