Interference Mitigation Through Inter-Cell Interference Coordination Using Virtual PRB Allocation in 4G Networks

This paper proposes a distributed and coordinated resource allocation algorithm in multi-cell MIMO-OFDMA systems. Firstly, each cell classifies mobile users into cell-edge and cell-center users based on a dynamic threshold aiming to avoid throughput loss. Secondly, each cell independently and dynamically allocates physical resource blocks (PRBs) to its cell-center users using a recursive resource allocation algorithm where the effective SINR metric is investigated. After that, each cell aggregates the unused sub-carriers by its cell-center users to construct virtual PRBs. These latter are intended to be allocated to cell-edge users. Here, each cell informs its neighboring cells, via messages exchange, about its unused sub-carriers and their corresponding SINRs. If two or more cells share the same unused sub-carrier, a new collision avoidance algorithm is applied to avoid the inter-cell interference. Then, each cell constructs its virtual PRBs based on radio resource exchange between eNodeBs. After virtual PRB allocation, a power allocation procedure is performed and an adaptive modulation and coding algorithm is executed. Simulation results demonstrate that the proposed scheme permits to enhance the system performance in cell-edge and cell-center region compared to well-known algorithms.