In wireless communication, Random Access Procedures are crucial for establishing connections and synchronization between User Equipment (UE) and the network. There are two types of Random Access Procedures:
1.) Contention Based Random Access (CBRA):
🔹MSG1: UE initiates access request to the gNB.
🔹MSG2: gNB responds with important information like temporary identifier and timing advance.
🔹MSG3: UE transmits scheduled data using allocated resources.
🔹MSG4: gNB confirms access and provides further instructions for communication.
2.) Non Contention or Contention Free Random Access (CFRA):
🔹RA Preamble Assignment: gNB assigns a unique identifier (RA preamble) to the UE.
🔹MSG1: UE signals its intent to access the network using the assigned RA preamble.
🔹MSG2: gNB responds to MSG1 with details such as timing advance and allocated uplink resources.