Hi All.
Does anyone explain what is the difference here between Serving beam PCI and PCI (Best measured by UE) and Serving PCI and Beam Index?
Serving beam PCI is the PCI of the beam that the UE is currently using. It is measured at the UE.
PCI (Best measured by UE) is the PCI of the beam that the UE has determined is the best beam to use, based on its own measurements. This may not be the same as the serving beam PCI, if the UE has not yet switched to the best beam.
Serving PCI is the PCI of the beam that the UE is currently using. It is measured at the UE. In general, PCI (Best measured by UE) is the most accurate measure of the PCI of the beam that the UE should use.
However, Serving beam PCI may be more useful for certain applications, such as identifying the beam that the UE is currently using.
Beam Index is a unique identifier for a beam. It is used by the UE to identify and select beams.
The key difference between the SS-RSRP Serving beam and the SS-RSRP Best Beam is that the SS-RSRP Best Beam is based on the UE’s own measurements, while the SS-RSRP Serving beam is measured at the UE.
This means that SS-RSRP Best Beam may be more accurate, but it may also be delayed if the UE has not yet completed its measurements.
Is the beam index be same (0) for all PCIs?
No, the beam index is not the same for all PCIs.
The beam index is a unique identifier for a beam, and it can be different for different PCIs.
For example, a gNB may have multiple antennas, and each antenna may have multiple beams.
Each beam will have a unique beam index.
But in picture it is showing only (0).
A few possible reasons why the beam index is showing the same (0) for all PCIs.
The gNB is not using beamforming. The UE is not able to measure the beam index or there is a problem with the gNB or UE software.
If the gNB is not using beamforming, then there will be no beam index. Beamforming is a technique that uses multiple antennas to focus the signal in a specific direction. It is used to improve the signal quality and range.
If the UE is not able to measure the beam index, then it will display the same beam index for all PCIs. This can happen if the UE is not configured correctly, or if there is a problem with the UE hardware.
If there is a problem with the gNB or UE software, then this can also cause the beam index to be displayed incorrectly.
Thank you ! 
Additional info :
If the network using multibeam antenna & Huawei Equipment, you can check on Node B side:
CellBeamIndex parameter, wheter it is defined or not.
Sometime it’s not configured yet, because if Beamforming is not activated it will not affective.
This is Airtel.
If it is FDD cell, there can be only one sector beam.
Here is EN-DC, LTE UL+DL CA, LTE FDD, LTE CA, LTE TDD as serving in drive plot.