Mobile communication networks typically use one standard or a plurality of standards for mobile communication such as the so-called GSM standard (Global System for Mobile communication), the GPRS standard (General Packet Radio System), the UMTS standard (Universal Mobile Telecommunication System) or the LTE (Long term evolution) standard.
For the LTE standard and as well for the UMTS standard, the standardization organization 3GPP has defined so-called ANR functionalities (Automatic Neighbor Relationship) to identify and organize neighbor relationships among cells which is the basis for mobility of mobile device (user equipments) within the mobile communication network or parts thereof.
One basic pre-requisite and assumption for the use of ANR functionalities, but generally also for mobility of user equipments within the mobile communication network, is that an information that is assigned, by the operator of the mobile communication network, to a radio cell is unique, and hence it is possible to identify that radio cell, at least on a local level (i.e. not necessarily network-wide). This information is often referred to as the so-called physical cell identifier information or PCI (Physical Cell Identifier): it identifies the radio cell of the mobile communication network as a short identifier but, at least in general, it is not (necessarily) unique regarding the complete mobile communication network (i.e. network-wide).
At the very least, the assumption should be verified—in view of using ANR functionalities—that the pair of values of:                the physical cell identifier information, and        the center frequencyis locally unique to identify that radio cell, i.e. on a local level within the mobile communication network (i.e. not necessarily network-wide), it should be possible to unambiguously identify any radio cell via the physical cell identifier information and the center frequency.        
However, due to the fact that the number of possible physical cell identifier values is limited (e.g. limited to 504 different values according to the LTE standard), and especially in complex network situations involving a plurality of network layers, the problem of a confusion and/or of conflicts regarding the physical cell identifier information and/or regarding the pair of values of the physical cell identifier information and the center frequency (so-called PCI confusions or PCI conflicts) occur.
In contrast to the physical cell identifier information assigned to the radio cells of the mobile communication network, the cell global identifier information (also called CGI, Cell Global Identifier) is a unique identifier for a radio cell, i.e. its knowledge enables to precisely identify the radio cell (at least network-wide, if not globally). However, the cell global identifier information is a more extensive information than the physical cell identifier information (typically being “longer”, i.e. comprising a higher number of digits) and, especially due to this property, is not read (i.e. decoded or received), by a standard user equipment and at least not in any case, for the purposes of normal mobility measurements, i.e. in case that the user equipment detects that the radio link with the serving base station entity becomes weaker (and the radio signals of another base station entity of another radio cell becomes stronger) and hence a handover procedure could be required.
Accordingly, situations of a confusion and/or of conflicts regarding the physical cell identifier information (and/or regarding the physical cell identifier information and the center frequency) often result in a reduced level of quality of service provided by the mobile communication network to the respective users of the mobile devices or user equipments, lead to a reduced mobility in the mobile communication network and might end up in a dropped connection of the mobile device or user equipment.