Achieving spectral and energy efficiencies in multi-cell networks

The focus of this paper is targeted towards multicell networks, when dense frequency reutilization is used in a given operating area by evolved Nodes B (eNodeB). The ensuing Inter-Cell Interference (ICI) harms the radio transmissions and degrades the performances. Thus, a certain degree of ICI coordination (ICIC) between the eNodeBs is required to manage the resources and minimize the interference level. This paper addresses the problem of ICIC in the downlink of LTE OFDMA-based systems, where the power level selection of resource blocks (RBs) is portrayed as a sub-modular game in the context of self-organizing networks. The existence of Nash equilibriums (NEs) for that type of games shows that stable power allocations can be reached by selfish eNodeBs. To attain these NEs, we propose a decentralized algorithm based on Best Response dynamics to achieve those equilibriums. In order to evaluate our proposal, we compare the obtained results to an optimal global CoMP (Coordinated Multi-Point) solution where a central controller is the decision maker [2]. Numerical simulations assessed the good power efficiency of the proposed distributed approach in comparison with the centralized approach for CoMP.