Comparative Study of Scheduling Algorithms and Almost Blank Subframe for LTE HetNets

With dramatically increasing demand for data usage in the LTE Heterogeneous Networks (HetNets), traffic offloading techniques have been used to balance the load among the network tiers in order to enhance the overall system performance. The Cell Range Expansion (CRE) and Almost Blank Subframe (ABS) are the two major techniques under the enhanced Inter-Cell Interference Coordination (eICIC), which are aimed at increasing overall system performance while keeping low interference toward cell edge users. In general, a scheduling algorithm is also one major issue affecting the system efficiency. In this paper, different scheduling schemes, i.e. Round Robin (RR), Proportional Fairness (PF), Best-Channel Quality Identification (Best-CQI), Maximum Throughput (Max-TP) and Resource Fairness (RF), are investigated. The study focuses on the comparison of the system performance when operating with different schedulers as well as under different CRE and ABS parameters. The results are observed through the system level simulation in terms of average throughput, peak throughput, edge throughput, and fairness.