A universal frequency reuse scheme in LTE‐A heterogeneous networks

Abstract

Effective inter-cell interference mitigation has been extensively studied because of its outstanding cell-edge signal quality improvement capability. Conventional static inter-cell interference coordination strategies, including fractional frequency reuse and soft frequency reuse, have received much attention owing to their effectiveness in mitigating interference and low complexity in implementation. However, they are less effective when dealing with dense uneven traffic distributions and dynamic traffic demands and thus incur low spectrum utilization in some cells and spectrum shortage in others. This paper proposes a universal frequency reuse scheme in a two-layer Long Term Evolution-Advanced heterogeneous network to ensure good throughput for all user equipment (UE), especially UEs at cell edge. The proposed scheme allows each cell to use all the spectrum resources, limited by an orderly regulation of all sub-bands. This scheme minimizes the potential occurrence probability of inter-cell co-sub-band interference through an intra-cell sub-band resource management. Furthermore, a graph-theoretic based sub-band allocation algorithm is developed to optimize UE throughput performance, especially for the cell-edge low signal to interference noise ratio UEs. A comprehensive performance comparison among different frequency reuse schemes is conducted by considering performance metrics, including cell-edge throughput, average throughput, and signal to interference noise ratio cumulative distribution function. Simulation result shows that the universal frequency reuse scheme outperforms other two schemes significantly. Copyright © 2016 John Wiley & Sons, Ltd.