Mobility Sensitivity Analysis for LTE-Advanced HetNet Deployments with Dual Connectivity

A mobility performance sensitivity analysis is presented for Dual Connectivity cases where the users can be served simultaneously by a macro and a small cell. The performance is assessed for the 3GPP generic simulation scenario and for two site-specific cases, with the aim of comparing the results coming from these different scenarios. The site-specific scenarios are based on detailed three-dimensional topography map data and advanced ray-tracing techniques. It is generally found that the first order statistics and overall conclusions are in good alignment for the considered environments. However, there are also a number of differences in the obtained performance results for the different cases, e.g. in terms of small cell time-of-stay statistics. The explicit modeling of streets and building topology, propagation in street canyons, etc., is found to have an important impact on the mobility performance. Especially the time-of-stay statistics and the location of handover failures differ between generic 3GPP case and the site-specific modeling scenarios. So in conclusion, trends and observations from simulations based on the 3GPP scenario are valuable, but should be supplemented by results from site-specific scenarios, as additional performance-determining effects are more accurately represented for such cases.