Tomas Lundborg

Large scale mobility measurement in two metropolitan networks

User mobility and the resulting handover rate is an important design parameter for cellular mobile systems. In this study handover rates are presented based on live traffic measurements from two commercial and mature WCDMA networks. Performance monitoring (PM) counters have been used enabling collection of a large number of samples, millions of connected minutes from thousands of cells. Two different networks have been studied, one Asian city network and one European city network. The mobility was very similar in both networks. The network average WCDMA active set update rate was around 5 per connected minute. An access technique independent cell change rate is approximated to 2.5 per connected minute based on delete events. This is the network average, but there are cells with more than 8 cell changes per connected minute. This handover rate means a shorter cell residence time than found in earlier channel holding measurements, less than 24 seconds compared to around 40 seconds. The mobility was higher at daytime than at nights in both networks.