Minimizing Rate Variability With Effective Resource Utilization in Cellular Networks

While one of the main features of 5G networks is provisioning very high rates with low (or no) variability to cellular users, it has been shown that this turns out to be very ineffective for operators because it leads to an abundance of unused network resources. Yet, reallocating the unused resources to the same users, after providing them with the same constant rate, increases back the variability in data rates. A more efficient way would be to provide different low-variability data rates to the users depending on their channel conditions while trying to bring the wasted resources to the lowest possible extent. To that end, in this paper, two approaches are considered; one with reserved resources for every user and the other where the amount of resources is decided on the fly, depending on their current channel conditions. Then, for each approach, we look at different allocation policies and derive the corresponding maximum achievable constant rate for every user jointly with the level of resource utilization, showing which policy is more beneficial. Further, the performance is evaluated on a real 5G trace using both extensive simulations and real measurements conducted on OpenAirInterface. Results show that no-resource reservation policies increase the utilization of resources and data rates at the expense of increased rate variability across all the users. Moreover, all the policies proposed in this paper outperform state-of-the-art approaches by at least $\text{2}\times$, bringing the waste of resources down to 15%.