What is difference between PCI in 4G LTE and PCI in 5G NR

Physical Cell ID (PCI) is one of the most important cell’s identifier in the wireless network of 4G and 5G system.It is PHY cell id which is required for DL synchronization.

 PCI planning is one of the most important steps in 4G and 5G network planning and construction. To design PCI properly and efficiently will increase resource utilization and QoS of the 4G and 5G system for subscribers. Poor planning results in PCI collisions or conflicts which impact network performance.

The PCI value is created from two components – PSS and SSS Primary Synchronization Signal and Secondary Synchronization Signal.

After successful decode of PSS and SSS you UE will able to calculate its PCI using the below formula:

PCI = (3 × SSS) + PSS

How 4G PCI is calculated ?

PSS has 3 values 0,1 and 2 and is created using Zad-off Chu sequence.

PSS helps to accomplish slot and symbol synchronization in the time domain.

SSS has 168 values 0 to 167 and is produced using concatenation of 2 m-sequences (max length sequence)

SSS aids to achieve radio frame synchronization

PCI = (3 * 167) + 2 = 503

So PCI values will vary from 0 to 503 LTE supports 504 unique PCIs

How 5G PCI is calculated ?

PSS has 3 values 0,1 and 2 and created using m-sequence

SSS has 336 values 0 to 335 and generated using product of 2 m-sequences

In 5G-NR, the basic structure of PSS is the same but the number of SSS are increased

PCI = (3 * 335) + 2 = 1007

So PCI values will vary from 0 to 1007. 5GNR supports 1008 unique PCIs .

Conclusion:

5G NR has double of the PCI’s compared to LTE 4G

Don’t miss our 5G NR RF Planning Training to learn more about Planning and design in 5G, below more details :

5G New Radio RF Planning Training