Neighbor Cell List Management in Wireless Heterogeneous Networks

This paper introduces the problem associated to long neighbour cell lists as a result of introducing and reserving identity codes for small cells in heterogeneous networks. It is shown that the number of reserved codes needs to be sufficiently high or identity confusions and collisions are inevitable. This results in long neighbouring lists that effectively increases measurement periods and handover failures subsequently. To address the issue, a standard compliant mechanism is proposed in that the neighbouring cell list contains only relevant macrocell neighbours and is updated dynamically according to the users' measurements. Simulation scenario used in this study refers to a part of the Vodafone 3G network deployed in south east of Berlin and the results confirms performance improvement both in terms of handover success rate as well as impact on battery life of the users' equipment when the proposed scheme is deployed.