Realistic Implementation of X 2-based Interference Management for LTE Femtocells

Femtocells address one of the main issues of current broad-band mobile communication networks, that is, the lack of in-building coverage. Apart from their benefits related to the better coverage and throughput, femtocells have several drawbacks, being the most significant one the interference with the macro-cellular network and with other femtocells. This paper focuses on LTE femtocells and tackles the problem of interference between femtocells using existing signalling and communication protocols. Two alternatives for resource allocation are proposed where each femtocell has a set of preferential RBs in which it can transmit even if it causes interferences to the neighbour femto-cells. Whenever an excessive femto-to-femto interference would require coordination, the proposed solutions enhance spectrum efficiency and reduce interferences. Results indicate that the scheme that combines load indication messages and measurement reports from the users improves significantly the capacity without requiring complex computations in the femtocell.