Hi there, Community!
This post brings you more knowledge on the topic PCI confusions vs. PCI collisions. Please see more details as you read the materials further down.
BACKGROUND INFORMATION
The PCI conflict problem that can occur in LTE radio networks, and also it’s subcategories – confusions and collisions. Furthermore, the steps taken towards achieving the best approach to detect PCI conflicts, by using different models to analyse KPI daily measurements are presented.
Each LTE cell has two identifiers, with different purposes – the Global Cell ID and the PCI. The Global Cell ID is used to identify the cell from an Operations, Administration and Management (OAM) perspective. The PCI has a value in the range of 0 to 503, and is used to scramble the data in order to allow mobile phones to separate information from different eNB. Since a LTE network may contain a much larger number of cells than the 504 available numbers of PCIs, the same PCI must be reused by different cells.
However, an UE, which is any device used directly by an end-user to communicate, cannot distinguish between two cells if both have the same PCI and frequency bands; this phenomenon is called a PCI conflict. PCI conflicts can be divided into two situations – PCI confusions and PCI collisions.
PCI CONFUSIONS VS. PCI COLLISIONS
Source: https://www.researchgate.net/figure/a-Collision-b-Confusion_fig1_261152401
A PCI confusion occurs whenever a E-UTRAN cell has two different neighbor E-UTRAN cells with equal PCI and frequency.
A PCI collision happens whenever a E-UTRAN cell has a neighbor E-UTRAN cell with identical PCI and frequency.
A good PCI plan can be applied to avoid most PCI conflicts. By contrast, it can be difficult to do such a plan without getting any PCI conflicts in a dense network. Moreover, network changes, namely increased power of a cell and radio channel fading, can lead to PCI conflicts. These changes might result in a mobile phone that detects a cell different from one of the PCI plan.
PCI conflicts can lead to an increase of dropped calls due to failed handovers as well as an increased channel interference.
