Performance Analysis of Decoupled UL/DL User Association in Wireless-Powered Massive MIMO-Aided Heterogeneous Networks

In this paper, we investigate the performance of downlink-uplink decoupled (DUDe) user association in wireless-powered full-duplex (FD) heterogeneous networks (HetNets), where different association strategies are deployed for uplink and downlink. We consider a two-tire HetNet with half duplex (HD) massive multiuser multiple-input multiple-output (MIMO) macrocell base stations (MBSs) to relax the coverage reduction, FD small cell base stations (SBSs) and FD user equipments (UEs) to improve spectral efficiency. During the energy transmission phase, UEs are associated to MBSs/SBSs based on the mean maximum received power (MMP) scheme and charge their batteries. During the data transmission phase, each UE downloads packets from the same MBSs/SBSs, while UEs upload packets to the nearest SBSs using the harvested energy. We develop an analytical framework to analyze the average UL power transfer and derive closed-form expressions for the UL and DL coverage probabilities of the proposed DUDe in massive MIMO aided HetNets.