An Optimization Framework for LTE eICIC and Reduced Power eICIC

Abstract

enhanced Inter-Cell Interference Coordination (eICIC) is used in LTE heterogeneous networks to reduce interference in the small cell expansion region. Service areas of small cells are often expanded by a Cell Selection Offset (CSO) to increase their traffic uptake and offload macro cell traffic. eICIC relies on Almost Blank Subframes (ABS) or Reduced Power Almost Blank Subframes (RP-ABS) to manage interference between macro and small cellular layers. Gains achieved from deploying intra-carrier small cells are highly dependent on the optimization of eICIC parameters. This paper provides a novel optimization formulation to achieve optimal small cell CSOs and macro cell ABS or RP-ABS patterns. The performance of the outlined optimization framework is evaluated by state-of-the-art LTE system level simulations. Simulation results indicate an average network capacity gain of 19.4% from optimizing ABSeICIC parameters, and a 22.8% gain from optimizing RP-ABSeICIC parameters. Similarly, a 42.2% average gain in user data rates is achieved from optimizing ABS-eICIC parameters, and a 45.9% gain from optimizing RP-ABS-eICIC parameters.

eICIC Optimization Improvements in Downlink Resource Allocation in LTE-A HetNets

“…The algorithm has provable guarantees, and furthermore, it accounts for network topology, traffic load and the interference map for picocells and macrocells. The authors of [12] propose optimized ABS patterns and CSB values jointly and efficiently for large networks. System level simulation results illustrate significant gains from the optimization in both network capacity and data rate fairness.…”