5G NR Cell Scan and RACH Procedure Poster

Introducing a comprehensive poster detailing the 5G NR Cell Scan Procedure and RACH Procedure. This visual guide offers a step-by-step overview of how UE initiate’s the cell scan procedure upon powering on, delving into the intricacies of 5G cell scanning. Additionally, it presents a thorough illustration of the 5G NR RACH procedure, serving as a valuable reference diagram to enhance understanding of RACH concepts and facilitate in-depth analysis.

NR Cell Scan, nr rach

When you power on your 5G NR device, it undergoes a critical process called cell scan to establish a connection with the network. Here’s a breakdown of this procedure:

1. Power ON: Upon powering on, the User Equipment (UE) initiates the cell scan procedure.

2. Cell Scan Start: The UE scans a specific frequency range or a list of pre-configured frequencies to detect potential 5G NR cells broadcasting signals.

3. Decoding the Master Identity Block (MIB): During the scan, the UE decodes the Master Identity Block (MIB) from any detected cell. The MIB provides essential information like the cell identity and Primary Synchronization Signal (PSS) characteristics.

4. Obtaining System Information Block 1 (SIB1): Using the information from the MIB, the UE identifies the Physical Downlink Control Channel (PDCCH) configuration for System Information Block 1 (SIB1). It then decodes SIB1, which contains crucial system-wide information such as neighboring cell details and cell selection parameters.

5. Cell Scan End: Once the UE has gathered sufficient information from potential cells and SIB1, the cell scan process concludes.

6. Ranking and Camping: Based on the collected data, the UE ranks the available cells using various criteria like received signal strength and cell selection parameters. It then “camps” on the best-ranked cell, meaning it synchronizes with that cell’s timing and frequency for further communication.

7. Decoding SIB1 of the Best Cell: After camping, the UE decodes the complete SIB1 of the chosen cell, accessing detailed information specific to that cell and its neighboring cells.

8. Reading RACH Configuration: From SIB1, the UE retrieves the Random Access Channel (RACH) configuration, which defines how the UE can request access to the network for data transmission or control signaling.

9. Initiating RACH Procedure: Finally, equipped with the necessary information, the UE initiates the RACH procedure, formally requesting access to the network through the chosen cell.

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