Resource Allocation for Practical Two-Tier Heterogeneous Cellular Networks

Heterogeneous cellular Network (HetNet) has emerged as a promising technology for 5G that can be used to meet high demand of data rate and better quality of service (QoS) performance. However, the performance of HetNet will depend on how the scarce resources such as frequency, time, power and spatial resource are shared among UEs in the system and also how interference is controlled. In this work, we mainly consider how the powers and spatial directions (normalized beamforming vectors) are shared among UEs. We formulate our spatial resource allocation problem as maximizing the weighted sumrate of HetNet while fulfilling some power, QoS and interference constraints. This optimization problem is NP-hard and nonconvex. We reformulate it into a convex feasibility problem and solve using SeDumi. Our proposed power resource allocation problem is formulated as maximizing the sum-rate of each cell while satisfying the minimum QoE1 of each UE. This problem is convex and therefore can be solved efficiently using CVX (a package for specifying and solving convex programs). Simulation results of our proposed method when compared with other existing methods show significant improvement.