The Value of PCI Planning in LTE
LTE network needs not only good RSRP levels, but also high Signal to Interference plus Noise Ratio (SINR). If PCI is not planned well, it will cause high interruption of the Reference Signal (RS). This situation may then result in an effective lack of signal coverage. Physical Cell ID (PCI) is one of the most important cell’s identifier in the wireless network of LTE system. Therefore, PCI planning is one of the most important steps in LTE network planning and construction. To assign PCI correctly and efficiently will increase resource utilization and QoS of the LTE system for subscribers. Poor planning results in PCI conflicts or collisions which impact network performance.
The first step to resolving any problem is knowing there is an issue to begin with. An automated daily audit, with data directly from the OSS configuration files, provides the clear picture of frequency and severity of problems. Mapping of confusions and collisions with weighting by neighbor interactions assists with prioritizing the resolutions. These may include simple neighbor definition clean-up or PCI changes.
After identifying the problems, market engineers can utilize the Ad-hoc planning module to determine a new PCI plan for the problem cells. A market for this US-based LTE operator utilized the IMNOS (Integrated Mobile Network Optimization Software) modules – Audit and Ad-hoc Planner – to resolve PCI problems with their network. The severity of impact varies based on interaction with neighbors and overall traffic.