Analysis of the impact of PCI planning on downlink throughput performance in LTE

The planning of Physical Cell Identities (PCI) has a strong impact on the performance of Long Term Evolution cellular networks. Although several PCI planning schemes have been proposed in the literature, no study has quantified the performance gains obtained by these schemes. In this paper, a comprehensive performance analysis is carried out to quantify the impact of PCI planning on user quality of service and network capacity in the downlink of LTE. First, an analytical model for the influence of PCI planning on reference signal collisions is developed. Based on this model, different PCI planning schemes are tested on a dynamic system-level simulator implementing a macrocellular scenario. During the analysis, both Voice-over-IP and full buffer services over time-synchronized and non-time synchronized networks are considered. Results show that call blocking and dropping for real-time services and user throughput for non-real time services can be significantly improved by a proper PCI plan.