User Association and Channel Allocation in 5G Mobile Asymmetric Multi-Band Heterogeneous Networks

With the proliferation of mobile terminals, the continuous upgrading of services, 4G LTE networks are showing signs of weakness. To enhance the capacity of wireless networks, millimeter waves are introduced to drive the evolution of networks towards multi-band 5G heterogeneous networks. The distinct propagation characteristics of mmWaves, microwaves, as well as the vastly different hardware configurations of heterogeneous base stations, make traditional access strategies no longer effective. Therefore, to narrowing the gap between theory, practice, we investigate the access strategy in multi-band 5G heterogeneous networks, taking into account the characteristics of mobile users, asynchronous switching between uplink, downlink of pico base stations, asymmetric service requirements, user communication continuity. We formulate the problem as integer nonlinear programming, prove its intractability. Thereby, we decouple it into three subproblems: user association, switch point selection, subchannel allocation, design an algorithm based on optimal matching, spectral clustering to solve it efficiently. The simulation results show that the proposed algorithm outperforms the comparison methods in terms of overall data rate, effective data rate, number of satisfied users.