Optimal distributed frequency planning for OFDMA femtocell networks

Femtocell networks have gained momentum due to their important benefits, such as improved indoor coverage, higher areal spectral efficiency, enhanced signal quality, among others. Those benefits are only achievable if adequate deployment decisions and efficient resource allocation techniques are able to assure the seamless co-existence among Femtocell Access Points (FAPs) within the femtocell tier and between FAPs and macrocell users. In this work, we study the frequency planning problem on the femtocell tier deployed on a closed access mode and using a dedicated spectrum. A novel radio resource allocation technique that performs a mid/long-term frequency planning for the FAPs in the femtocell tier is proposed. It is concluded in this paper that the Dynamic Frequency Planning (DFP) algorithm based on the Branch and Bound technique is able to find the optimal frequency planning according to any desired criterion and that the proposed algorithm is suitable for implementation in a distributed 4G femtocell network regarding signaling overhead and latency aspects.