Backhaul-Aware Cell Selection Policies in 5G IAB Networks

IAB is a feasible and economical solution to deploy ultra-dense cells in the 5G networks, where access and wireless backhaul links share the same spectrum. IAB eliminates the need to connect ultra-dense cells to the core network through the wired backhaul. However, mmWave backhauling and multihop topology imposes new constraints on the 5G IAB network that become a hindrance to its effective performance. In this paper, we elaborate on cell selection and present a few cell selection policies designed explicitly for IAB networks. Unlike the popular RSRP based policy that may lead to load unbalance in the IAB network, the proposed policies are devised after considering the backhaul constraints and end-to-end performance requirements. The performance of these policies is investigated using system-level simulations. These policies have shown tremendous improvement in achieving cell-edge throughput while maintaining comparable average UE throughput. The policies provide better load balancing and topology in the IAB network than the RSRP based policy.