Centralized dynamic resource allocation scheme for femtocells exploiting graph theory approach

This paper focuses on mitigation of cross-tier and co-tier interference for dense deployment of the femtocells (FAPs). We propose a centralized dynamic radio resource allocation scheme exploiting graph theory approach. The FAPs either utilize an overlapping allocation mode (OAM) or a non-overlapping allocation mode (NAM). The allocation mode is dynamically selected by a control unit (CU) depending on the changing interference pattern among individual FAPs. The FAPs are assumed to be mutually interfered if interference is higher than a specified threshold. In order to create interference matrix among the FAPs, we use Bron-Kerbosch algorithm. In case the FAPs are assessed to be interfered, the CU also allocates resources in the NAM mode in dynamic nature in dependence on current traffic load of the FAPs. The results indicate that the proposal offers significantly higher throughput for the macro users than other competitive schemes. Simultaneously, femto users perform satisfactorily as well.