A physical cell identity self-organization algorithm in LTE-advanced systems

Self-configuration of radio parameters is one of the key features in long term revolution advanced (LTE-Advanced) systems. Physical cell identity (PCI) is cell identifier on the physical layer which can be used to create synchronization signals, including Primary Synchronization Signals (PSS) and Secondary Synchronization Signals (SSS). PCI planning is one of the most important parts of self-configuration because of its significant role in cell search. This paper aims to propose a PCI allocation algorithm based on graph theory. The algorithm works by utilizing Floyd algorithm to obtain cellular hops and calculating the weight of each cell, and forming cell clusters according to PCI allocation results. Finally, a simulation is demonstrated to evaluate the performance of the PCI allocation algorithm. The results show that the algorithm can achieve a tradeoff between decreasing interference and increasing PCI reuse.