Modified Adaptive 2-Step ICIC for Distributed MIMO System with User Clustering

Distributed multi-input multi-output (MIMO) system with user equipment (UE) clustering can boost up area spectrum efficiency by performing UE scheduling independently in all clusters. However, UEs locating at cell-edge area suffer from strong inter-cell interference (ICI). We have proposed a de-centralized adaptive 2-step ICI coordination (ICIC) which employs UE classification and selection of additional fractional frequency band based on received interference level, but UE clustering has not been considered. In this paper, we modify the adaptive 2-step ICIC so as to fit to distributed MIMO system with UE clustering. Multiple cell-edge UEs are scheduled simultaneously and adjust the cell-center UE/cell-edge UE timeslot ratio to keep an average UE connection probability similar to system without ICIC. Simulation results show that the modified adaptive 2-step ICIC improves the cell-edge UE link capacity without significantly degrading entire-cell UE link capacity.