Joint dl/ul decouple user association in microwave and mmwave enabled beyond 5g heterogeneous networks

Abstract

Beyond fifth-generation (5G) heterogeneous networks (HetNets) are facing the challenge of accommodating enormous mobile users and data traffic with scarce spectrum resources in the microWave ( \mu Wave) band. In this work, we consider both challenges in HetNets comprising large size, high power base station (LHB) and relay operating in \mu Wave band and small size, low power base station (SLB) and device-to-device (D2D) operating in millimeter wave (mmWave) band. We formulate user association optimization problems to pitch user association schemes based on downlink uplink decoupled (DU-DPL) access against traditional downlink uplink coupled (DU-CPL) access in HetNets to gauge the performance of these access schemes in terms of accommodating users and spectrum efficiency in \mu Wave and mmWave bands. Formulated problems are non-deterministic polynomial-time hard (NP-hard) and solved using epsilon -optimal algorithm. Simulation results show the edge of DU-DPL access over DU-CPL access in terms of users association and spectrum efficiency.