Method for eliminating physical cell identifier PCI collisions of pico base stations in the area of a macro base station of a mobile communication system

A mobile communication system and method for managing physical cell identifiers PCIs is provided, such that PCI confusions are eliminated. The method includes transmitting macro base station information from a terminal to a first pico base station; transmitting a Neighbor Relation Table NRT including the macro base station information from the first pico base station to a Self Organizing Network (SON) server; determining, at the SON server, whether a second pico base station using same Physical Cell Identifier (PCI) as the first pico base station exists by comparing a previously stored NRT from the second pico base station with the NRT received from teh first pico base station; and reallocating, at the SON server, upon determining that the second pico base station uses the same PCI as the first pico base station and that the first and second base stations have matching macro base station information in their NRTs, new PCIs to the first and second pico base stations.