3GPP Analyzer

PRACH

Physical Random Access Channel

Physical LayerIntroduced R99

Definition

The uplink physical channel used by the UE to initiate random access, enabling uplink timing synchronization and initial access.

Evolution Across Releases

  • NR (Rel-15) introduced a 2-step RACH procedure alongside the traditional 4-step procedure, finalized in Rel-16.

Related Specifications