Performance analysis of transport and radio load balancing strategies for BS assignment in mobile access networks

In mobile access networks, base station (BS) assignment mechanisms are mainly driven by radio conditions since it is generally assumed that the limiting factor is the air interface. This assumption has been proven to be very reasonable when circuit voice was the dominant service and backhaul capacity provisioning accounting for the peak rate at the BSs was an economically feasible option. However, as more efficient air interface technologies are introduced along with higher data rate services, a growing concern is that the transport part of the mobile network can also represent a bottleneck. In this paper we analyze a BS assignment strategy that simultaneously exploits load balancing in both the radio interface and the transport backhaul links. The BS assignment problem is solved by means of simulated annealing heuristics under different deployment scenarios comprising partially-limited backhaul radio access networks (RANs) and the presence of traffic hotspots. Results achieved for the proposed BS assignment strategy are compared to those obtained by common strategies such as minimum path loss (MPL) and load balancing radio (LBR).