Inproceedings,
Joint User Association and Resource Allocation in Heterogeneous Cellular Networks: Comparison of Two Modeling Approaches
31th International Teletraffic Congress (ITC 31), Budapest, Hungary, (2019)
Abstract
The performance of different combinations of user
association (UA) and resource allocation (RA) in heterogeneous
cellular networks has been extensively studied using a classic
modeling approach based on system snapshots. There have been
also many studies focusing on the dynamics of the system
using queueing models. These modeling approaches are rarely
compared with each other though they each bring different
insights to the design problem. In this paper, we consider a
queueing model-based approach to study the interplay of UA and
RA, and compare the results to those obtained using snapshot
models. Specifically, we formulate three different joint UA and
RA optimization problems corresponding to the following three
performance metrics: the maximum achievable arrival rate, the
average system delay, and the maximum per-user delay. These
problems are non-convex integer programs. We have therefore
developed numerical techniques to compute either their exact
solutions or tight lower bounds. We obtain results for different
combinations of RA and UA schemes, and compare the trends
with those obtained via the snapshot approach. The trends on
RA are very similar, which we take as a cross-validation of the
two modeling approaches for this kind of problem. The trends on
user association are somewhat different which indicates a lack
of robustness of the results and the need for a careful validation
of UA models.
